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40034GC11
Production 1.1
June 2001
D33131
Oracle iDS Forms: Build Internet Applications II
Volume 1 • Instructor Guide
Author
Ian Purvis
Technical Contributors and Reviewers
Cem Ayberkin
Gunnar Bohrs
Brian Boxx
Libor Danek
Laurent Dereac
Brain Fry
Pam Gamer
Pascal Gibert
Thierry Guibert
Ellen Gravina
Norris Gray
Anthony Hargreaves
Ali Hiemstra
Barry Hiern
Ursula Hovy
Sarah Jones
Jan Keuben
Aija Lehtonen
Regis Louis
Kenji Makita
Jayne Marlow
Sergei Pechersky
Milos Randak
Jonas Reborg
Bryan Roberts
Candace Stover
Hiroyuki Sugiyama
Laura Tejero
Jack Walsh
Publisher
Shane Mattimoe
Copyright Oracle Corporation, 2001. All rights reserved.
This documentation contains proprietary information of Oracle Corporation. It isprovided under a license agreement containing restrictions on use and disclosureand is also protected by copyright law. Reverse engineering of the software isprohibited. If this documentation is delivered to a U.S. Government Agency of theDepartment of Defense, then it is delivered with Restricted Rights and thefollowing legend is applicable:
Restricted Rights LegendUse, duplication or disclosure by the Government is subject to restrictions forcommercial computer software and shall be deemed to be Restricted Rightssoftware under Federal law, as set forth in subparagraph (c) (1) (ii) of DFARS252.227-7013, Rights in Technical Data and Computer Software (October 1988).
This material or any portion of it may not be copied in any form or by any meanswithout the express prior written permission of the Worldwide Education Servicesgroup of Oracle Corporation. Any other copying is a violation of copyright law andmay result in civil and/or criminal penalties.
If this documentation is delivered to a U.S. Government Agency not within theDepartment of Defense, then it is delivered with “Restricted Rights,” as defined inFAR 52.227-14, Rights in Data-General, including Alternate III (June 1987).
The information in this document is subject to change without notice. If you findany problems in the documentation, please report them in writing to EducationProducts, Oracle Corporation, 500 Oracle Parkway, Box 659806, RedwoodShores, CA 94065. Oracle Corporation does not warrant that this document iserror-free.
Oracle Developer, Oracle Server, and PL/SQL are trademarks or registeredtrademarks of Oracle Corporation.
All other products or company names are used for identification purposes only,and may be trademarks of their respective owners.
.....................................................................................................................................................Oracle iDS Forms: Build Internet Applications II iii
.....................................................................................................................................................Contents
Contents
PrefaceProfile xv
Related Publications xvi
Typographic Conventions xvii
IntroductionIntroduction I-2
Course Content I-3
Lesson 1: Creating a Menu ModuleIntroduction 1-3
Components of the Menu Module 1-5
The Default Menu 1-7
The Menu Editor 1-9
Creating a Menu Module 1-11
Module Properties 1-13
Menu Properties 1-15
Menu Item Properties 1-17
Menu Item Types 1-19
Menu Item Command Types 1-21
Implementing Menu Toolbars 1-23
Storing the Menu Module 1-25
Attaching the Menu Module 1-27
Pop-up Menus 1-29
Summary 1-31
Practice Overview: Lesson 1 1-33
Practice 1 1-34
Lesson 2: Managing Menu ModulesIntroduction 2-3
Using PL/SQL in Menu Item Code 2-5
Useful Built-in Menu Subprograms 2-7
.....................................................................................................................................................iv Oracle iDS Forms: Build Internet Applications II
.....................................................................................................................................................Contents
Showing and Hiding the Current Menu 2-9
Managing Menu Security 2-11
Defining Security Roles 2-13
Assigning Access to Menu Items 2-15
Summary 2-17
Practice Overview: Lesson 2 2-19
Practice 2 2-20
Lesson 3: Programming Function KeysIntroduction 3-3
Key Triggers 3-5
Defining Key Triggers 3-7
Characteristics of Key Triggers 3-9
Classification of Key Triggers 3-11
Using Key Triggers 3-15
Association with Other Interface Controls 3-17
Summary 3-19
Practice Overview: Lesson 3 3-21
Practice 3 3-22
Lesson 4: Responding to Mouse EventsIntroduction 4-3
What Are Mouse Events? 4-5
Responding to Mouse Movement 4-7
Responding to Mouse Button Actions 4-11
Summary 4-15
Practice Overview: Lesson 4 4-17
Practice 4 4-18
Lesson 5: Controlling Windows and Canvases ProgrammaticallyIntroduction 5-3
Using Window-Interaction Triggers 5-5
Built-ins for Manipulating Windows 5-7
Built-ins for Manipulating Canvases 5-9
.....................................................................................................................................................Oracle iDS Forms: Build Internet Applications II v
.....................................................................................................................................................Contents
Working with Tab-Style Canvases 5-11
Windows and Blocks 5-15
Manipulating Window Properties Programmatically 5-17
Closing Windows 5-19
Manipulating Windows in Web-Deployed Forms 5-21
Sizing Windows for Web-Deployed Forms 5-23
Display Large Data Blocks in a Window 5-25
Managing Images for Web-Deployed Forms 5-27
Summary 5-29
Practice Overview: Lesson 5 5-31
Practice 5 5-32
Lesson 6: Defining Data SourcesIntroduction 6-3
Data Source Types 6-5
Basing a Data Block on a FROM Clause Query 6-7
Basing a Data Block on a Stored Procedure 6-9
Example of a Query Using a REF Cursor Procedure 6-11
Example of Query Using a Table of Records Procedure 6-13
Example of DML Using a Stored Procedure 6-15
Deciding Whether to Use a REF Cursor or a Tableof Records 6-17
Data Block Wizard 6-19
Data Block Properties 6-21
Data Source Guidelines 6-23
Summary 6-27
Practice Overview: Lesson 6 6-29
Practice 6 6-30
Lesson 7: Working with Oracle8i Objects in Form BuilderIntroduction 7-3
What Are Object Types? 7-5
Review of Objects 7-7
Object REFs 7-9
.....................................................................................................................................................vi Oracle iDS Forms: Build Internet Applications II
.....................................................................................................................................................Contents
Supported Oracle8i Features 7-11
How Oracle Forms Developer Treats Objects 7-13
Object Type Displays 7-15
Creating Data Blocks Based on Oracle8i Objects 7-17
Selecting Object Table Columns 7-19
Selecting Object Column Attributes 7-21
Blocks with REF Lookups 7-23
The REF Column Value 7-25
LOVs for REFs 7-27
Summary 7-29
Practice Overview: Lesson 7 7-31
Practice 7 7-32
Lesson 8: Controlling Data Block RelationshipsIntroduction 8-3
Creating a Relation 8-5
Block Coordination 8-7
Coordinate Blocks Using REFs 8-9
Characteristics of Relation-Handling Triggers 8-11
Principles of Relation-Handling Code 8-13
Obtaining Relation-Handling Information 8-15
Implementing a Coordination-Type Toggle 8-17
Forcing a Commit Per Master 8-19
Summary 8-21
Practice Overview: Lesson 8 8-23
Practice 8 8-24
Lesson 9: Building Multiple Form ApplicationsIntroduction 9-3
OPEN_FORM to Invoke Additional Forms 9-5
Closing Forms 9-7
Navigating Between Forms 9-9
Transaction Processing for Opened Forms 9-11
CALL_FORM to Invoke Additional Forms 9-13
.....................................................................................................................................................Oracle iDS Forms: Build Internet Applications II vii
.....................................................................................................................................................Contents
Transaction Processing for Called Forms 9-15
NEW_FORM to Invoke Additional Forms 9-19
Controlling Open Forms and Called Forms Together 9-21
Different Ways of Invoking Forms 9-23
Using Form Parameters 9-25
Parameter Lists 9-29
Creating and Manipulating Parameter Lists 9-31
Passing Data Between Forms 9-33
Summary 9-35
Practice Overview: Lesson 9 9-37
Practice 9 9-38
Lesson 10: Working with Record GroupsIntroduction 10-3
Record Groups 10-5
Using Record Groups 10-7
Defining Record Groups at Design Time 10-9
Built-in Functions for Controlling Record Groups 10-11
Defining Query Record Groups Programmatically 10-17
Defining Nonquery Record Groups Programmatically 10-19
Manipulating Record Group Rows 10-21
Manipulating Selected Record Group Rows 10-23
Defining Global Record Groups 10-25
Manipulating List Items Programmatically 10-27
Implementing Dynamic List Items 10-29
Adding Values to Combo Boxes 10-31
Summary 10-33
Practice Overview: Lesson 10 10-35
Practice 10 10-36
Lesson 11: Using Reusable ComponentsIntroduction 11-3
Reusable Components 11-5
Reusable Components List 11-7
.....................................................................................................................................................viii Oracle iDS Forms: Build Internet Applications II
.....................................................................................................................................................Contents
The Calendar Class 11-11
Calendar Object Group Content 11-13
Built-in for Manipulating the Calendar 11-15
Summary 11-17
Practice Overview: Lesson 11 11-19
Practice 11 11-20
Lesson 12: Using Java with Web-Deployed FormsIntroduction 12-3
Java and Oracle Forms Developer 12-5
Java in Web-Deployed Forms 12-7
The Forms Applet 12-9
Defining Fonts for Web-Deployed Forms 12-11
Pluggable Java Components 12-13
What Is a Bean Area? 12-17
Hosting a JavaBean 12-19
How a JavaBean Communicates 12-21
Communicating with the JavaBean 12-23
Exploiting Oracle8i Features 12-25
How to Create JavaBeans 12-27
The Java Importer 12-29
The Java Importer Tool 12-31
Summary 12-33
Practice Overview: Lesson 12 12-35
Practice 12 12-36
Lesson 13: Using Server Features in Form BuilderIntroduction 13-3
Using Oracle Database Server Functionality in Forms 13-5
Dealing with PL/SQL Code 13-7
PL/SQL8 Support 13-9
PL/SQL8 Scalar Data Types 13-11
Unsupported Oracle Forms Developer PL/SQL8 Features 13-13
Handling Errors Raised by the Oracle Database Server 13-15
.....................................................................................................................................................Oracle iDS Forms: Build Internet Applications II ix
.....................................................................................................................................................Contents
Performing DDL with FORMS_DDL 13-19
Using FORMS_DDL 13-21
Summary 13-23
Practice Overview: Lesson 13 13-25
Practice 13 13-26
Lesson 14: Applying TimersIntroduction 14-3
Timers 14-5
Handling Timer Expiration 14-7
Creating a Timer 14-9
Modifying a Timer 14-11
Deleting a Timer 14-13
Summary 14-15
Practice Overview: Lesson 14 14-17
Practice 14 14-18
Lesson 15: Including Charts and ReportsIntroduction 15-3
Including Charts by Using the Chart Wizard 15-5
Chart Item Properties 15-11
Reporting Within Form Builder 15-13
Report Object Properties 15-15
Working with Reports 15-17
Summary 15-23
Practice Overview: Lesson 15 15-25
Practice 15 15-26
Appendix A: Practice SolutionsPractice 1 Solutions A-2
Practice 2 Solutions A-6
Practice 3 Solutions A-9
Practice 4 Solutions A-11
Practice 5 Solutions A-12
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.....................................................................................................................................................Contents
Practice 6 Solutions A-15
Practice 7 Solutions A-16
Practice 8 Solutions A-18
Practice 9 Solutions A-21
Practice 10 Solutions A-24
Practice 11 Solutions A-27
Practice 12 Solutions A-30
Practice 13 Solutions A-33
Practice 14 Solutions A-35
Practice 15 Solutions A-37
Appendix B: Table Descriptions and DataSummit Sporting Goods Database Diagram B-2
S_CUSTOMER Description B-3
S_CUSTOMER Data B-4
S_DEPT Description and Data B-8
S_EMP Description B-9
S_EMP Data B-10
S_ITEM Description B-13
S_ITEM Data B-14
S_ORD Description and Data B-16
S_PRODUCT Description B-17
S_PRODUCT Data B-18
S_REGION Description and Data B-22
S_TITLE Description and Data B-23
Oracle8i Objects: Types, Tables B-24
Appendix C: Mouse Movement EventsIntroduction C-2
Drag and Drop C-4
Summary C-6
Appendix D: Introduction to Oracle8i Object FeaturesIntroduction D-3
.....................................................................................................................................................Oracle iDS Forms: Build Internet Applications II xi
.....................................................................................................................................................Contents
New Oracle8i Data Types D-5
Object Types D-7
Creating Oracle8i Objects D-11
Object Columns D-13
Object Views D-15
INSTEAD-OF Triggers D-17
Referencing Objects D-19
Displaying Oracle8i Objects in the Object Navigator D-21
Summary D-29
Appendix E: Menu Run-Time ParametersIntroduction E-3
Substitution Parameters E-5
Defining a User-Named Substitution Parameter E-7
Substitution Parameter Built-ins E-9
Validating a Substitution Parameter Value E-11
Summary E-13
Appendix F: Handling Server-Side ErrorsIntroduction F-3
Obtaining the Cause of Declarative-Constraint Violations F-5
Customizing Oracle Server Error Messages F-7
Example Procedure for Handling Oracle Server Errors F-9
Summary F-13
Appendix G: EMP_PKG PackagePackage Specification G-2
Package Body G-4
Appendix H: Working with ActiveX ControlsIntroduction H-3
What Are VBX, OCX, and ActiveX Controls? H-5
Comparison of VBX, OCX, and ActiveX Controls H-7
ActiveX in Form Builder H-9
Implementing an ActiveX Control H-11
.....................................................................................................................................................xii Oracle iDS Forms: Build Internet Applications II
.....................................................................................................................................................Contents
Inserting an ActiveX Control in an ActiveX Control Item H-13
Importing ActiveX Control Methods and Events Packages H-15
Setting and Getting ActiveX Control Properties H-17
Invoking ActiveX Control Methods H-21
Responding to ActiveX Control Events H-23
Handling Exceptions H-25
Registering an ActiveX Control H-27
Summary H-29
Appendix I: Using Oracle Server Roles at Run TimeUsing Oracle Server Roles at Run Time I-3
Procedures for Managing Roles I-7
.....................................................................................................................................................xiv Oracle iDS Forms: Build Internet Applications II
.....................................................................................................................................................Preface
Instructor NoteGeneral course information for instructors:
PowerPoint Slides The slide show provides many builds to facilitate your explanation. Of course, you can modify these builds if you prefer, depending upon your familiarity with PowerPoint.
All slides include a small arrow at the bottom of the screen that is displayed on the final build, so that you know when one slide finishes and the next slide begins. On the last slide of a lesson the arrow points to the left instead of the right.
If you modify a build, make sure that this arrow is the last object in the build order.
Demonstrations A set of demonstrations is provided to help you with your explanations. If there is more than one Web deployed demo form module within a lesson, you can use the appropriate lesson Webmenu form module to launch your demos.
Practice Sessions Students might want to view the form that they are asked to produce in each question. Solution files of all forms are available in the SOLNS directory.
.....................................................................................................................................................Oracle iDS Forms: Build Internet Applications II xv
.....................................................................................................................................................Profile
Profile
Before You Begin This CourseBefore you begin this course, you should have the following qualifications:
• Thorough knowledge of:
- Creating simple applications with Oracle Forms Developer Form Builder
- Creating SQL query statements
• Working experience of:
- Creating PL/SQL constructs, including conditional statements, procedures, and functions
- Creating PL/SQL stored (server) procedures and functions
• Knowledge of using a graphical user interface (GUI)
• Knowledge of using a Web browser, and downloading HTML pages with a Uniform Resource Locator (URL)
PrerequisitesThe following instructor-led training (ILT) course: Oracle 9iDS Forms: Build Internet Applications I
Suggested Follow-up Courses• Oracle 9iDS Reports: Build Internet Reports
• Oracle 9iAS Forms Services: Deploy Internet Applications
How This Course Is OrganizedOracle 9iDS Forms: Build Internet Applications II is an instructor-led course featuring lectures and hands-on exercises. Online demonstrations and written practices reinforce the concepts and skills introduced.
.....................................................................................................................................................xvi Oracle iDS Forms: Build Internet Applications II
.....................................................................................................................................................Preface
Related Publications
Oracle Publications
Additional Publications• read.me file
• relnotes.pdf file
Title Part Number
Oracle Forms Developer and Oracle Reports Developer Guide-lines for Building Applications, Release 6i
A73073-02
Oracle Forms Developer Getting Started, Release 6i A73154-01
Oracle Forms Server Release 6i Patch 2: Deploying Forms Appli-cations to the Web with the Oracle Internet Application Server
A86202-01
.....................................................................................................................................................Oracle iDS Forms: Build Internet Applications II xvii
.....................................................................................................................................................Typographic Conventions
Typographic Conventions
Typographic Conventions in TextConvention Element ExampleBold italic Glossary term (if
there is a glossary)The algorithm inserts the new key.
Caps and lowercase Buttons,check boxes, triggers,windows
Click the Executable button.
Select the Can’t Delete Card check box.
Assign a When-Validate-Item trigger . . .
Open the Master Schedule window.Courier new,case sensitive (default is lowercase)
Code output, directory names, filenames,passwords, pathnames,URLs, user input, usernames
Code output: debug.seti(’I’,300);
Directory: bin (DOS), $FMHOME (UNIX)
Filename: Locate the init.ora file.
Password: Use tiger as your password.
Pathname: Open c:\my_docs\projects
URL: Go to http://www.oracle.com
User input: Enter 300
Username: Log on as scott
Initial cap Graphics labels (unless the term is a proper noun)
Customer address (but Oracle Payables)
Italic Emphasized words and phrases,titles of booksand courses, variables
Do not save changes to the database.
For further information, see Oracle7 Server SQL Language Reference Manual.
Enter user_id@us.oracle.com, where user_id is the name of the user.
Quotation marks Interface elements with long names that have only initial caps; lesson and chapter titles in cross-references
Select “Include a reusable module component” and click Finish.
This subject is covered in Unit II, Lesson 3, “Working with Objects.”
Uppercase SQL column names, commands, functions, schemas, table names
Use the SELECT command to view information stored in the LAST_NAME column of the EMP table.
.....................................................................................................................................................xviii Oracle iDS Forms: Build Internet Applications II
.....................................................................................................................................................Preface
Typographic Conventions in Code
Typographic Conventions in Navigation PathsThis course uses simplified navigation paths, such as the following example, to direct you through Oracle Applications.
(N) Invoice—>Entry—>Invoice Batches Summary (M) Query—>Find (B) Approve
This simplified path translates to the following:
1 (N) From the Navigator window, select Invoice—>Entry—>Invoice Batches Summary.
2 (M) From the menu bar, select Query—>Find.
3 (B) Click the Approve button.
N = Navigator, M = Menu, B = Button
Arrow Menu paths Select File—>Save.Brackets Key names Press [Enter].Commas Key sequences Press and release these keys one at a time:
[Alt], [F], [D]Plus signs Key combinations Press and hold these keys simultaneously:
[Ctrl]+[Alt]+[Del]
Convention Element ExampleCaps and lowercase Oracle Forms
triggersWhen-Validate-Item
Lowercase Column names, table names
SELECT last_name
FROM s_emp;
Passwords DROP USER scott
IDENTIFIED BY tiger;
PL/SQL objects OG_ACTIVATE_LAYER
(OG_GET_LAYER (’prod_pie_layer’))
Lowercase italic Syntax variables CREATE ROLE role
Uppercase SQL commands and functions
SELECT userid
FROM emp;
Convention Element Example
I-2 Oracle iDS Forms: Build Internet Applications II......................................................................................................................................................
......................................................................................................................................................Lesson I:
Introduction
Aim of the CourseAfter completing this course, you should be able to do the following:
• Create, modify and attach menu documents to Oracle Forms Developer Internet applications
• Ensure application security with Oracle8i database roles
• Code triggers that respond to function keys
• Respond to mouse movement and mouse button actions
• Manipulate windows and canvases
• Choose appropriate data sources for data blocks
• Work with Oracle8i objects in Form Builder
• Create and manage multiple Internet form applications
• Manage transaction processing in multiple Oracle Forms Developer Internet applications
• Create and modify Record Groups programmatically
• Build forms with Reusable Components
• Enhance the User Interface with JavaBeans
• Manage Server side features
• Create Timers
• Include charts and reports in Oracle Forms DeveloperInternet applications
Oracle iDS Forms: Build Internet Applications II I-3......................................................................................................................................................
......................................................................................................................................................Course Content
Course ContentThe lesson titles show the topics we cover in this course, and the usual sequence of lessons. However, the daily schedule is an estimate, and may vary for each class.
Day 1
Day 2
Lesson Number Lesson Name
1 Creating a Menu Module
2 Managing Menu Modules
3 Programming Function Keys
4 Responding to Mouse Events
Lesson Number Lesson Name
5 Controlling Windows and Canvases Programmatically
6 Defining Data Sources
7 Working with Oracle8i Objects in Form Builder
8 Controlling Data Block Relationships
9 Building Multiple Form Applications
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......................................................................................................................................................Lesson I:
Day 3
Lesson Number Lesson Name
10 Working with Record Groups
11 Using Reusable Components
12 Using Java with Web-Deployed Forms
13 Using Server Features in Form Builder
14 Applying Timers
15 Including Charts and Reports
1-2 Oracle iDS Forms: Build Internet Applications II......................................................................................................................................................
......................................................................................................................................................Lesson 1: Creating a Menu Module
Instructor NoteTopic TimingLecture 50 minutes
Practice 40 minutes
Total 90 minutes
Copyright Oracle Corporation, 2001. All rights reserved.®
Objectives
After completing this lesson, you shouldbe able to do the following:
• Identify the components of a menu
• Create, save, and attach menu modules
• Set menu properties by using theProperty Palette
• Create menu toolbars
• Create pop-up menus
Oracle iDS Forms: Build Internet Applications II 1-3......................................................................................................................................................
......................................................................................................................................................Introduction
Introduction
OverviewBy default, each form module uses the same menu structure, called the Default menu. This lesson teaches you how to customize this menu and how to create your own menu modules. You will also learn how to enhance your application by including menu toolbars and pop-up menus.
ObjectivesAfter completing this lesson, you should be able to do the following:
• Identify the different components of a menu module
• Create, save, and attach menu modules
• Set menu properties by using the Property Palette
• Create menu toolbars
• Create pop-up menus
1-4 Oracle iDS Forms: Build Internet Applications II......................................................................................................................................................
......................................................................................................................................................Lesson 1: Creating a Menu Module
Instructor NoteDemonstration: Use orders.fmb to explain the components. Open the Default menu, menudef.mmb, to illustrate the hierarchical structure of a menu.
Copyright Oracle Corporation, 2001. All rights reserved.®
Components of the MenuModule
Mainmenu
Menu item
Individual menu
Menu toolbar
Copyright Oracle Corporation, 2001. All rights reserved.®
Hierarchical Structure of a Menu
Menumodule
Individualmenu
Submenu
Menuitems
Menuitem
Menuitem
Individualmenu
Menuitems
Oracle iDS Forms: Build Internet Applications II 1-5......................................................................................................................................................
......................................................................................................................................................Components of the Menu Module
Components of the Menu Module
What Is a Menu Module?A menu module is a hierarchically structured object that provides a quick and easy method for operating your Forms application. Like the form module, the menu module is one of the main components of an application.
Each menu module displays as a pull-down menu. A pull-down menu comprises a set of options, displayed horizontally under the application window title. Each option can represent a submenu or an action. Selecting a submenu displays a vertical list. Selecting an action executes the action.
What Is a Menu?A menu is a list of related options. Each option performs a different action. You can create three menu types in Forms:
• Main menu:
- Displays horizontally in the menu bar
- Contains options (menu items) that are typically individual menus
• Individual menu: Displays vertically
• Submenu: Displays vertically and to the right of the menu item that calls it
What Is a Menu Item?A menu item is an option that you can choose from a menu. Each menu item has an associated command that enables the user to perform an action.
What Is a Menu Toolbar?A menu toolbar is a toolbar of iconified buttons that represent individual items from your menu. For a menu module, you can have a vertical and a horizontal menu toolbar.
1-6 Oracle iDS Forms: Build Internet Applications II......................................................................................................................................................
......................................................................................................................................................Lesson 1: Creating a Menu Module
Instructor NoteOpen the Default menu (menudef.mmb), and show the menu items in the menu editor.
Copyright Oracle Corporation, 2001. All rights reserved.®
Default Menu
Action
SaveClear AllPrintPrint SetupExit
Edit
CutCopyPasteEditDisplay List
Block
PreviousNextClear
Field
PreviousNextClearDuplicate
Record
PreviousNextScroll UpScroll DownInsertRemoveLockDuplicate Clear
Query
EnterExecuteCancelLast CriteriaCount HitsFetch Next Set
Help
HelpKeysListDisplay ErrorDebug
Oracle iDS Forms: Build Internet Applications II 1-7......................................................................................................................................................
......................................................................................................................................................The Default Menu
The Default Menu
What Is the Default Menu?The Default menu is not a separate menu module and is built in to every form module. The Default menu includes standard commands for editing, navigating, and database interaction, such as Action—>Save.
When you build a form module, it automatically uses the Default menu. The Default menu is internal to Oracle Forms Developer. You can replace the Default menu with a custom menu. A custom menu is stored in a separate module that has a suffix of .mmb. A custom menu that is exactly the same as the Default menu, menudef.mmb, ships with Oracle Developer Forms.
Examining the Default MenuYou can look at the structure of the Default menu by opening the file called menudef.mmb. This file contains a menu module with an identical structure to that of the Default menu. Once you have opened the menudef.mmb module, you can see its objects in the Object Navigator.
You can see that the menu module consists of a main menu (starting point), menus, and menu items.
1-8 Oracle iDS Forms: Build Internet Applications II......................................................................................................................................................
......................................................................................................................................................Lesson 1: Creating a Menu Module
Technical NoteBy default, the Menu Editor displays a pull-down menu, with the top-level menu displayed horizontally. If you are developing a full-screen menu, you may want to display the top-level menu vertically, so that the display matches the way your menu will appear at run time. To change the orientation, click the Switch Orientation button.
Instructor NoteIn the Menu Editor, the key sequences [Ctrl] + the down arrow and [Ctrl] + the right arrow create, respectively, a menu item below and to the right of an existing object.
Use the Default menu (menudef.mmb) to show the Menu Editor functionalities. Show the steps to move a menu or a menu item. Show the steps to copy a menu to another level. Demonstrate that if you move a submenu to a parent item with the Command Type property set to PL/SQL or Null, Form Builder displays an alert.
Copyright Oracle Corporation, 2001. All rights reserved.®
The Menu Editor
Displaymenu
CreateDown
CreateRight
SwitchOrientation
Menu tab Expandedmenu
Collapsedmenu
Oracle iDS Forms: Build Internet Applications II 1-9......................................................................................................................................................
......................................................................................................................................................The Menu Editor
The Menu Editor
What Is the Menu Editor?The Menu Editor is a graphical design facility for laying out, modifying, and viewing menu modules and their objects. Use the Menu Editor to carry out all of your menu design work.
Two Ways to Display the Menu Editor• Double-click the icon to the left of the menu module entry in the Object
Navigator.
• Select Tools—>Menu Editor.
Tools Specific to the Menu Editor ToolbarYou have seen the majority of the tools from the Menu Editor toolbar in the Layout Editor; however, some are specific to the Menu Editor.
Tool Function
Display Menu
Determines the highest level menu that the Menu Editor displays. (Choose from all the menus in your menu module.)
Create Down Creates a new menu item below the currently active one
Create Right Creates a new menu item to the right of the currently active one
Switch Orientation
Allows display of the top-level menu vertically or horizontally
1-10 Oracle iDS Forms: Build Internet Applications II......................................................................................................................................................
......................................................................................................................................................Lesson 1: Creating a Menu Module
Instructor NoteCreate the following menu:
File Edit Query
Save Clear Record Enter
Exit Clear Block Execute
Sort > By Order Id
By Order Date
Copyright Oracle Corporation, 2001. All rights reserved.®
Creating a Menu Module
Oracle iDS Forms: Build Internet Applications II 1-11......................................................................................................................................................
......................................................................................................................................................Creating a Menu Module
Creating a Menu ModuleThe first step when creating a menu is to define a new menu module by using the Object Navigator. Once the module is created, you need to create menus and menu items in the Menu Editor. When the Menu Editor is displayed, it shows a menu called MAIN_MENU, with one item labeled New Item.
Creating a Main Menu from the Menu EditorTo create menu items for the Main menu, select New Item from the Menu Editor (it is usually selected already).
1 Type a menu label to replace the default label.
2 Click the Create Right icon.
3 Type a new label to replace the default label.
4 Repeat steps 2 and 3 to add more items to the Main menu.
Note: The label is the text that is displayed for the menu item at run time. The label may differ from the name, which you can use programmatically and which must follow PL/SQL naming conventions.
Creating an Individual Menu1 In the Main menu, select the parent item.
2 Click the Create Down icon.
3 Type a new label to replace the default label.
4 Repeat steps 2 and 3 to add more menu items to the current individual menu.
Note: Forms places a shaded rectangle, or handle, to the left of the first menu item. You can use it to move the menu along with all its items.
Creating a Submenu1 Select the parent item on the individual menu.
2 Click the Create Right icon.
3 Replace the default label.
4 Select Menu—>Create Down to add another item to the submenu.
5 Replace the default label.
6 Repeat steps 4 and 5 to add more submenu items.
1-12 Oracle iDS Forms: Build Internet Applications II......................................................................................................................................................
......................................................................................................................................................Lesson 1: Creating a Menu Module
Instructor NoteDo not spend a long time going through all the menu module properties; instead point out that they are here for convenience. Also, context-sensitive help is available.
Copyright Oracle Corporation, 2001. All rights reserved.®
Menu Module Properties
Main MenuMenu DirectoryMenu FilenameStartup CodeShare Library with Form
Use SecurityModule Roles
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......................................................................................................................................................Module Properties
Module Properties
Property Description
Main Menu Property that specifies the name of the individual menu in the module that is the main or starting menu at run time
For a pull-down menu, the main menu is automatically set to the name of the first menu that you create. Users cannot navigate above this menu in the menu hierarchy.
Menu Directory Path used by Forms as a pointer to the directory for the run-time .mmx file; only used by menu modules that are saved to the database
Menu Filename Filename used by Forms as a pointer to the run-time .mmx file; only used by menu modules that are saved to the database
Startup Code PL/SQL code executed when a menu module is loaded in memory
Share Library with Form
Property that enables the loading into memory of a single copy of a PL/SQL library, if this is the library used by the form module and the menu module
Use Security When set to Yes, this property enforces security at run time. (Set this property to No to test the menu module without having to be a member of any database role.)
Module Roles Property that displays the Menu Module Roles dialog box, where you can list the roles assigned to the menu module. (Roles defined must be assigned to individual menu items in the Menu Editor.)
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......................................................................................................................................................Lesson 1: Creating a Menu Module
Instructor NoteThe Tear-Off property is available for the Motif window manager.
Copyright Oracle Corporation, 2001. All rights reserved.®
Menu Properties
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......................................................................................................................................................Menu Properties
Menu Properties
Property Description
Tear-Off Menu Enables the menu to be dragged from the menu bar and repositioned elsewhere on the screen (available only if your window manager supports this feature)
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......................................................................................................................................................Lesson 1: Creating a Menu Module
Technical NoteRadio menu items must belong to a radio group. All of the radio items for a radio group must be contiguous on the same menu. Radio group names are internal names that are not displayed at run time.
Instructor NoteThe mappings of logical accelerator keys to physical device keys are defined in the run-time resource file. You must edit the resource file in Oracle Terminal to change the key mappings. You can also create additional accelerator keys in Oracle Terminal (ACCELERATOR6, ACCELERATOR7, and so on), which you can then associate with menu items in a menu module. If you wish to maintain key mapping for Web-deployed forms, you will need to edit the FMRWEB.res file; this does not require Oracle Terminal.
.
Copyright Oracle Corporation, 2001. All rights reserved.®
Menu Item Properties
• Enabled
• Label
• Menu Item Type
• Magic Item
• Menu Item RadioGroup
• Command Type
• Menu Item Code
• Submenu Name
• KeyboardAccelerator
• Icon in Menu
• Icon Filename
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......................................................................................................................................................Menu Item Properties
Menu Item Properties
Properties Specific to Menu Item
Defining Menu Access KeysForms indicates an access key by underlining one special character in the menu item. Users can then issue the menu item command by pressing a key combination such as [Alt] + [character].
Specifying the Underline Character
Menu Item Property FunctionEnabled Specifies whether the menu item is an active and mouse
manipulatable (Inactive menu items are displayed in grey.)Label Specifies the text that appears in the menu itemMenu Item Type Determines how this menu item displays (Choose from
Plain, Check, Radio, Separator, and Magic.)Magic Item Specifies that one of the predefined menu items for custom
menus should be usedMenu Item Radio Group Determines which radio group this menu item belongs toCommand Type Determines the type of command that this menu item calls
(Choose from Null, Menu, PL/SQL, or SQL*Plus.)Menu Item Code Specifies the command that this menu item invokesSubmenu Name Specifies the menu that this menu item invokesKeyboard Accelerator Determines which logical function key is associated with
this menu item (Accelerator keys are named ACCELERATOR1 through ACCELERATOR5.)
Icon in Menu Specifies if an icon is displayed in the menu itemIcon Name Specifies the name of the icon to display
Development Run Timeexecute query execute queryeXecute query eXecute queryExe&cute Query Execute QueryExecute &Query Execute Query
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......................................................................................................................................................Lesson 1: Creating a Menu Module
Copyright Oracle Corporation, 2001. All rights reserved.®
Menu Item Types
Plain
Check
Radio
Magic
Separator
Copyright Oracle Corporation, 2001. All rights reserved.®
Magic Items
• About
• Undo
• Clear
• Copy
• Cut
• Paste
• Help
• Quit
• Window
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......................................................................................................................................................Menu Item Types
Menu Item TypesYou can customize a menu by using different item types. In addition to plain menu items, Form Builder supports four types of special menu items.
Choosing a Menu Item Type
Magic ItemsSome Magic menu items include default functionality. Because a Magic item provides the standard actions of a graphical user interface (GUI), a copy or paste action is already defined at the menu level. All you need to do is set the item to the Magic type and define the desired action (standard or specific).
Menu Item Type DescriptionPlain Creates a standard text menu item (This is the Default menu item type.)Check Creates a menu item that has two possible states (Check menu item
functionality is defined using PL/SQL.)Radio Creates a set of mutually exclusive buttons, each representing a differ-
ent action (To assign a radio item to a group, enter the name of the group in the Menu Item Radio Group field in the Properties window.)
Separator Creates a separating horizontal line for grouping menu itemsMagic Creates a menu item with predefined functionality
Magic Item Command Type Default Functionality?About Undo
Any except Menu No. You must assign a command to these items to perform the desired function.
ClearCopyPasteCut
Null Yes. These items perform the default operations indicated by their names.
Help Menu No. You must define a submenu to be called by the Magic Help item, and you must assign commands to the items on that submenu.
Quit Null Yes. The Quit command, by default, exits from the form after asking the user to save any changes.
Window Null or Menu Yes. The window item invokes a default submenu that lists all open windows. Users can activate a window by selecting it from the submenu.
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......................................................................................................................................................Lesson 1: Creating a Menu Module
Copyright Oracle Corporation, 2001. All rights reserved.®
Menu Item Command Types
Null
Menu
PL/SQL
Plus
Form
Macro
Does not issue a command
Invokes a submenu
Executes a PL/SQL command
Spawns a process to SQL*Plus
Backward compatibility
Backward compatibility
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......................................................................................................................................................Menu Item Command Types
Menu Item Command TypesEvery menu item must have a valid command type. Most menu items execute PL/SQL commands, so their command type is PL/SQL. However, if a menu item is composed of submenus, the command type must be set to Menu. For example, all items on the Main menu must have the command type set to Menu. In this case, the Menu Item Code property is replaced by the Submenu Name property.
Choosing a Command Type
Note: The command types of Form, Plus and Macro are available for backward compatibility only.
Web Design TipIf you invoke the HOST command with Web-deployed forms, the required process will run on the Forms Services machine, not on the client. The client will not be able to view or participate in that process.
Viewing Menu Item CommandsTo view the menu item command associated with a menu item, you must take one of the following actions:
• Double-click the icon to the left of the menu item entry in the Object Navigator.
• Use the Menu Item Code or Submenu Name property in the Property Palette.
• Right-click on the menu item in the Object Navigator or Menu Editor and select PL/SQL Editor from the pop-up menu.
Command Type DescriptionNull Specifies that the menu item does not issue a command (The
NULL command is required for Separator menu items and optional for all other types of items.)
Menu Invokes a submenu (Valid submenu name is the name of the submenu to be invoked.)
PL/SQL (default) Executes a PL/SQL command (Valid menu item code is a PL/SQL block, including calls to built-in and user-named subprograms.)
Plus Specifies that the menu item code spawn a process to SQL*Plus.
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......................................................................................................................................................Lesson 1: Creating a Menu Module
Technical NoteFor more flexible or complex requirements, use the existing Toolbar canvas in form modules.
Instructor NoteThe Default menu toolbar works very well; however, building your own menu and menu toolbar is not so easy. For example, you have to create separator items for every space that you require to group the items. Also, the menu toolbar icons appear in exactly the same order as the menu options, which might not be what you want.
Demonstration: Use the menu that you created earlier, and set the properties to display the Save option in a menu toolbar. Use the save.ico file.
Copyright Oracle Corporation, 2001. All rights reserved.®
Implementing Menu Toolbars
Toolbar as part of menu module:
• Contains only buttons corresponding tomenu items
• Is displayed above “normal” toolbars
• Executes the same code as menu items
• Is enabled and disabled, visible andhidden, in synchronization withcorresponding menu item
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......................................................................................................................................................Implementing Menu Toolbars
Implementing Menu Toolbars
What Is a Menu Toolbar?A menu toolbar is a set of iconic buttons that represent individual items from a menu. When you create a custom form menu, you can specify that some of its items appear on a menu toolbar.
You need to provide icons to represent the associated buttons on the menu toolbar. If you use the default form menu, Form Builder attaches a default menu toolbar to your form automatically.
Menu toolbars allow developers to easily provide toolbar shortcuts to menu commands without duplicating code or effort.
Menu Toolbar Orientation You can assign menu items to a horizontal or a vertical menu toolbar. Form Builder locates a horizontal menu toolbar at the very top of a form (just beneath the pull-down form menu.) A vertical menu toolbar appears at the far left of a form (to the left of any existing toolbar canvas).
Creating a Menu ToolbarTo create a menu toolbar, you have to set up the following menu item properties.
Property Description
Visible in Horizontal Menu Toolbar
Specifies that the menu item should appear (represented by an icon) on the horizontal toolbar of a form
Visible in Vertical Menu Toolbar
Specifies that the menu item should appear (represented by an icon) on the vertical toolbar of a form
Icon Filename Specifies the name of the icon resource that you want to represent the iconic button. For Web-deployed forms, this should be a GIF file, otherwise use an ICO file.
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......................................................................................................................................................Lesson 1: Creating a Menu Module
Copyright Oracle Corporation, 2001. All rights reserved.®
Menu Module Storage
Menu module definition:
• .mmb
• Stored in files or database tables
Menu module executable:
• .mmx
• Stored in files
Menu module text:
• .mmt
• Stored in files
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......................................................................................................................................................Storing the Menu Module
Storing the Menu Module
Saving the Menu Module DefinitionAs with the form module, you can save your menu module definition to either of the following storage formats.
You can save your menu module definition by either of the following actions:
• Clicking the Save icon in the Object Navigator
• Selecting File—>Save
Creating an Executable VersionBefore you can use your customized menu module, you must create an executable version. To do so, select File—>Administration—>Compile File.
The resulting file that you create has the .mmx extension. A menu module executable file containing binary code is not portable between operating systems.
Storage Format DescriptionFile with .mmb extension
Menu module binary file, a binary representation of the menu structure that is portable between operating systems
Database table A table representation of the menu structure that is portable between databases
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......................................................................................................................................................Lesson 1: Creating a Menu Module
Technical NoteIf you want to use the Default menu without the associated menu toolbar, replace the value DEFAULT&SMARTBAR in the Menu Module property with DEFAULT only.
Copyright Oracle Corporation, 2001. All rights reserved.®
Form Module Properties
Menu moduleto use withthis formmodule
Specifythat menumoduleis storedin the file system
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......................................................................................................................................................Attaching the Menu Module
Attaching the Menu ModuleTo use your customized menu module, you must attach it to a form module. When you attach a customized menu module to a form module, you are effectively replacing the Default menu with your own menu module.
Attaching the Menu Module to the Form Module1 Ensure that the menu module has been generated.
2 Select the form module to which you want to attach your menu.
3 Invoke the Property Palette for the form module.
4 Replace the value DEFAULT&SMARTBAR in the Menu Module property with your menu module name.
5 Ensure that the Menu Source property has a value of:
a File, if the menu module is stored in the file system
b Database, if the menu module is stored in the database
6 Generate your form module.
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......................................................................................................................................................Lesson 1: Creating a Menu Module
Instructor NoteDemonstration: Use customers.fmb to demonstrate the pop-up menu. Navigate to the Comments item, and click the right mouse button.
Copyright Oracle Corporation, 2001. All rights reserved.®
What Is a Pop-up Menu?
Menu that appears on the screen at thelocation it was invoked
• Enables users toaccess commonly usedfunctions easily
• Is accessed by pressingthe right mouse button(Microsoft Windows andMotif)
Copyright Oracle Corporation, 2001. All rights reserved.®
Incorporating Pop-up Menus
• Pop-up menus are:
– Top-level objects in the object navigator,such as alerts or Data Blocks
– Built through the Property Palette orMenu Editor
– Defined in a form module
– Associated with items and canvaseswith a pop-up menu property
• Pre-Popup-Menu trigger providesdynamic control
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......................................................................................................................................................Pop-up Menus
Pop-up MenusPop-up menus are context-sensitive menus. You attach pop-up menus to an item or canvas, and display them by right click on that item or canvas. Pop-up menus enable end users to quickly access common functions and commands.
Pop-up menus are top-level objects in the Object Navigator (similar to alerts, blocks, canvases, and so on) and belong to a form module, as opposed to form menus, which belong to a separate menu module.
Items on a pop-up menu should be contextual to the menu’s associated objects. For example, you would not include text-editing items on the pop-up menu for a two-digit numeric item. However, you might include such items on the pop-up menu for a multiline text item.
Incorporating Pop-up Menus1 In the Object Navigator of a form, click the Pop-up Menus node, and
click the Create button on the toolbar.
Form Builder creates a pop-up menu and gives it a default name, such as MENU1.
2 In the Object Navigator or Menu Editor, create a main pop-up menu, submenus (if any), and menu items.
3 Assign commands to the menu items. You can select plain text, separators, check boxes, and option boxes for Menu items.
4 Attach the menu to items and canvases with a new Pop-up Menu property.
Rules for Incorporating Pop-up Menus• To show pop-up menus for a canvas, the mouse must be on the canvas
only.
• Pop-up menu items can be parents of submenus (if the platform allows it), magic menu items, or separators.
Pre-Popup-Menu TriggerYou can use this trigger to add dynamic control at run time, prior to displaying the menu. For example, you can use the trigger to identify the cursor context and navigate to a different item if necessary.
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......................................................................................................................................................Lesson 1: Creating a Menu Module
Copyright Oracle Corporation, 2001. All rights reserved.®
Summary
In this lesson, you should have learned to:
• Identify Menu module components
– The Default menu
– Menu properties
• Create a Menu module
• Associate Menu and form modules
• Create a Pop-up menu
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......................................................................................................................................................Summary
SummaryIn this lesson, you learned how to add, create, and customize menu modules.
The Menu Module Components• Main menu
• Menu
• Menu item
• Menu toolbar
The Default Menu• Automatically used with every form module
• Can be customized
Creating a Menu Module
Properties• Menu module properties
• Menu properties
• Menu item properties
Implementing a Menu Toolbar
Menu Module Storage• Database tables
• .mmb file extension
• .mmx file extension
• .mmt file extension
Menu Module and Form Module AssociationUsing the form module properties of Menu Module and Menu Source
Creating a Pop-up Menu• Incorporate pop-up menus
• Rules to incorporate pop-up menus
• Pre-Popup-Menu trigger
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......................................................................................................................................................Lesson 1: Creating a Menu Module
Instructor NoteThe practice overview in this lesson and the ones that follow are provided only as guides. Outline the practice in the level of detail appropriate for the course participants.
For this lab, use the DO_KEY built-in. At this stage of the course, students do not yet know this built-in. Explain it briefly and explain that it is covered in detail in Lesson 3.
Copyright Oracle Corporation, 2001. All rights reserved.®
Practice 1 Overview
This practice covers the following topics:
• Creating a simple menu module
• Incorporating some of the menu itemsin the menu toolbar
• Compiling and attaching the menu tothe ORDERS form
• Creating a pop-up menu
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......................................................................................................................................................Practice Overview: Lesson 1
Practice Overview: Lesson 1This practice guides you through creating a custom menu, a menu toolbar and a pop-up menu.
Practice Contents• Create a simple menu module
• Incorporate menu items in the menu toolbar
• Compile and attach a menu to a form
• Create a pop-up menu
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......................................................................................................................................................Lesson 1: Creating a Menu Module
Practice 1 1 Create a new menu module.
a Using the following screenshot as a guideline, create a new menu module called M_SUMMITXX where XX is your student coursenumber.
• File Menu
Label
Menu Item Type
Command Type
Menu Item Code
Visible in Menu
Visible in Horiz. Menu Toolbar
Icon Filename
Save Plain PL/SQL DO_KEY(’COMMIT_FORM’);
Yes Yes Save
Clear Plain PL/SQL DO_KEY(’CLEAR_FORM’);
Yes Yes Abort
Null1 Separator Null Yes Yes
Exit Plain PL/SQL DO_KEY(’EXIT_FORM’);
Yes Yes Exit
Null2 Separator Null No Yes
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......................................................................................................................................................Practice 1
• Edit Menu
• Sort By Menu
• Query Menu
LabelMenu Item Type
Magic Item
Command Type
Visible in Menu
Visible in Horiz. Menu Toolbar
Icon Filename
Cut Magic Cut Null Yes Yes Cut
Copy Magic Copy Null Yes Yes Copy
Paste Magic Paste Null Yes Yes Paste
Null3 Separator Null No Yes
Menu Label
Menu Item Type
Menu Item Radio Group
Command Type Menu Item Code
Order Id Radio Order_By PL/SQL SET_BLOCK_PROPERTY(’ s_ord’, order_by, ’ id’ ) ;
Customer Id Radio Order_By PL/SQL SET_BLOCK_PROPERTY(’ s_ord’, order_by,’ customer_id’ ) ;
Sales Rep Id Radio Order_By PL/SQL SET_BLOCK_PROPERTY(’ s_ord’, order_by,’ sales_rep_id’ ) ;
LabelMenu Item Type
Command Type Menu Item Code
Visible in Horiz. Menu Toolbar
Icon Filename
Enter Query
Plain PL/SQL DO_KEY(’ENTER_QUERY’);
Yes query
eXe-cute Query
Plain PL/SQL DO_KEY(’EXECUTE_QUERY’);
Yes execute
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......................................................................................................................................................Lesson 1: Creating a Menu Module
b Save as M_SUMMIT and compile the menu module.
c Attach the menu module to the ORDERS form.
d Save and compile the form module as ORDGXX where XX is your student course number.
e Run and test your ORDERS form.
2 Add pop-up menus to the CUSTOMERS form.
a Open the CUSTOMERS form module. Save as CUSTGXX where XX is your student course number.
b Copy the EDIT_MENU menu from your M_SUMMIT menu module to your CUSTOMERS form. Attach this pop-up menu to the Comments item.
c Save and compile the form module. Deploy your form to the Web to test.
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......................................................................................................................................................Lesson 2: Managing Menu Modules
Instructor NoteTopic TimingLecture 40 minutes
Practice 30 minutes
Total 70 minutes
Copyright Oracle Corporation, 2001. All rights reserved.®
Objectives
After completing this lesson, you shouldbe able to do the following:
• Control the menu programmatically
• Manage the interaction between the menu andform documents
• Implement application security throughthe menu
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......................................................................................................................................................Introduction
Introduction
OverviewIn this lesson, you will learn how to modify menus dynamically, as well as how to control application security through menu access.
ObjectivesAfter completing this lesson, you should be able to do the following:
• Control the menu programmatically by using menu built-ins
• Implement menu security by using both database roles and the appropriate built-ins
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......................................................................................................................................................Lesson 2: Managing Menu Modules
Instructor NoteThe DO_KEY built-in is explained in the next lesson. Stress that it is very important to use this built-in for generic coding.
Copyright Oracle Corporation, 2001. All rights reserved.®
Using PL/SQL in Menu ItemCode
• Similar to PL/SQL code in form triggers
• You can share code between a formmodule and a menu module by usingthe following:
– Libraries
– User-defined triggers
– DO_KEY built-in
Copyright Oracle Corporation, 2001. All rights reserved.®
Using PL/SQL in Menu ItemCode
• Menu modules generated independently
• Restrictions:
– Cannot directly reference values ofform objects
– Must use NAME_IN built-in function
– Cannot use direct assignment forform objects
– Must use COPY built-in procedure
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......................................................................................................................................................Using PL/SQL in Menu Item Code
Using PL/SQL in Menu Item Code
Using PL/SQL in Menu Item CommandsPL/SQL menu item commands are structurally similar to form triggers. In addition to standard application functions such as navigation, validation, and database interaction, you can use PL/SQL menu item commands to perform any actions.
Sharing Code Between a Form Module and a Menu ModuleYou can share code between form modules and menu modules in three ways:
• Setting up libraries and attaching them to the modules
• Creating user-defined triggers in the form module and calling them from a standard trigger in a form module, or calling them from a menu item in a menu module (Use EXECUTE_TRIGGER to fire the user-defined trigger.)
• Using the DO_KEY built-in to fire the corresponding trigger or function from a menu item
RestrictionsMenu modules are generated independently of form modules.
In PL/SQL command menu items:
• You cannot directly reference the value of form module objects.
• You must use the NAME_IN built-in function to determine the current value of the object.
• You cannot use direct assignment to set the value of a form module object.
• You must use the COPY built-in procedure.
ExampleIF :s_emp.title = ’MANAGER’ THEN ...-- INCORRECT
IF NAME_IN(’s_emp.title’) = ’MANAGER’ THEN ... -- CORRECT
:s_product.name := ’PUMP’; -- INCORRECT
COPY(’PUMP’, ’s_product.name’); -- CORRECT
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......................................................................................................................................................Lesson 2: Managing Menu Modules
Instructor NoteDemonstration: Use m_summit.mmb file to show examples of these built-ins.
Copyright Oracle Corporation, 2001. All rights reserved.®
Built-ins for Setting and GettingMenu Item Properties
• FIND_MENU_ITEM
• GET_MENU_ITEM_PROPERTY
• SET_MENU_ITEM_PROPERTY
• ITEM_ENABLED
• MENU_SHOW_KEYS
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......................................................................................................................................................Useful Built-in Menu Subprograms
Useful Built-in Menu SubprogramsYou can change certain menu characteristics dynamically at run time by using built-in subprograms.
Using some of these subprograms, you can get or change menu item properties. Using others, you can hide, display, or replace the current menu.
Setting and Getting Menu Item Properties
ExampleThis procedure finds the ID of a menu item before setting multiple properties.
DECLARE
mi_id MenuItem;
BEGIN
mi_id := Find_Menu_Item(’Preferences.AutoCommit’);
/* Determine the current checked state of the AutoCommit menu checkbox item and toggle the checked state */
IF Get_Menu_Item_Property(mi_id,CHECKED) = ’TRUE’ THEN
Set_Menu_Item_Property(mi_id,CHECKED,PROPERTY_FALSE);
ELSE
Set_Menu_Item_Property(mi_id,CHECKED,PROPERTY_TRUE);
END IF;
END;
Built-in DescriptionFIND_MENU_ITEM This function gets the ID of a menu item. The receiving
variable must be declared as a menu item type. GET_MENU_ITEM_PROPERTY This function returns the current value of the given
property for a specified menu item.SET_MENU_ITEM_PROPERTY This procedure modifies the state of a menu-item-
specific characteristic.ITEM_ENABLED This function returns the Boolean value TRUE when the
menu item is enabled and FALSE when the menu item is disabled.
MENU_SHOW_KEYS This procedure displays the Keys screen for the menu module at run time.
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......................................................................................................................................................Lesson 2: Managing Menu Modules
Technical Note REPLACE_MENU replaces the menu for all windows in the application. If you are using CALL_FORM, REPLACE_MENU replaces the menu for both the calling form and the called form with the specified menu.
Copyright Oracle Corporation, 2001. All rights reserved.®
Built-ins for Showing and Hidingthe Current Menu
REPLACE_MENU
Character mode built-ins:
• HIDE_MENU
• SHOW_MENU
• MENU_REDISPLAY
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......................................................................................................................................................Showing and Hiding the Current Menu
Showing and Hiding the Current Menu
ExampleUse a standard procedure to change which root menu in the current menu application appears in the menu bar. A single menu application may have multiple root menus, which an application can set dynamically at run time.
PROCEDURE Change_Root_To(root_menu_name VARCHAR2) IS
BEGIN
Replace_Menu(’MYAPPLSTD’, PULL_DOWN, root_menu_name);
END;
Built-in DescriptionREPLACE_MENU Replaces the current menu with a specific one, without mak-
ing it active (Use this procedure to modify the display style and security.)
HIDE_MENU Hides the current menu SHOW_MENU Displays the current menu without activating it MENU_REDISPLAY Redraws the current menu on the screen
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......................................................................................................................................................Lesson 2: Managing Menu Modules
Copyright Oracle Corporation, 2001. All rights reserved.®
Managing Menu Security
• Defining security roles
• Choosing roles for the menu module
• Assigning access to menu items
• Setting the Use Security property
Copyright Oracle Corporation, 2001. All rights reserved.®
What Is a Role?
Role
Users
Privileges
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......................................................................................................................................................Managing Menu Security
Managing Menu Security
What Is Menu Security?Using menu security, you can set up access rights on menu items. You can choose between two security policies for the users:
• Grant users access to all menu items in a module
• Grant users access only to specific menu items
When you want to deny a user access to a menu item, you can either hide the item or disable it.
What Is a Role?A role is a group of users sharing the same privileges. With Form Builder, you can manage menu security through Oracle server roles.
When you create a role, you can grant access privileges to each item individually. If access is granted only to some roles, only users belonging to those roles can access those items.
Using this feature, you can deliver the same application for different kinds of users.
Implementing Menu SecurityFirst, define the different types of users who will use the menus, their profiles, and their needs. Then follow the steps below:
1 Define security roles in the database.
2 Choose roles for the module in Form Builder.
3 Assign access to menu items.
4 Set the Use Security property.
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......................................................................................................................................................Lesson 2: Managing Menu Modules
Technical NoteIf Use Security is modified, you must recompile the menu module.
Copyright Oracle Corporation, 2001. All rights reserved.®
Menu Module Roles Window
Select Menu Module Roles:
Copyright Oracle Corporation, 2001. All rights reserved.®
Use Security Property
• Set to Yes to enforce security
• Set to No to ignore security: Enables thedeveloper to test the application
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......................................................................................................................................................Defining Security Roles
Defining Security Roles
Defining New RolesMenu security is based on the Oracle server roles. You can create these using SQL statements.
The following SQL commands implement roles.
Assigning Roles to the Menu ModuleTo associate a particular role with a menu item, you must define all the roles used in that menu module:
1 In the Object Navigator, select the menu module.
2 In the Properties window, select the Menu Module Roles property.
3 Click More... to open the Menu Module Roles dialog box.
4 Enter the names of the roles that you want to choose for this menu module.
5 Click OK to accept the roles list.
Note: The role must exist in the database.
Setting the Use Security PropertyThe Use Security property determines whether Form Builder should take account of the specified roles at run time.
When Use Security is set to Yes, Forms enforces security.
When Use Security is set to No:
• Forms ignores security.
• Your users can access all menu items.
• You can test your application without being a member of all roles.
Command ActionCREATE ROLE Creates a new roleGRANT Assigns the role to a user (This command allows you
to give a set of privileges to a user at one time.)ALTER USER...DEFAULT ROLE Controls which role is assigned by default to users
when they connect to the database
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......................................................................................................................................................Lesson 2: Managing Menu Modules
Instructor NoteYou can manipulate roles dynamically at run time by using Form Builder. For example, you can select views from the data dictionary to get information about existing roles. Subprograms belonging to the DBMS_SESSION package enable you to modify the roles that are used by the menu module to enforce security. Tell students that if they want more details about DBMS_SESSION, they can read Appendix I, “Using Oracle Server Roles at Run Time.”
Copyright Oracle Corporation, 2001. All rights reserved.®
Menu Item Roles Window
Select menu item roles:
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......................................................................................................................................................Assigning Access to Menu Items
Assigning Access to Menu ItemsAfter defining roles to use for the current menu module, you must specify the role or the roles that will have access to each menu item.
1 Select the desired menu item in the Menu Editor or in the Object Navigator.
2 Select the Item Roles property in the Properties window.
3 Click More... in the Menu Item Roles dialog box, which contains the role names associated with the menu module.
4 Select the role in the list to assign a role to the selected menu item.
5 Set the Display without Privilege property to specify how Forms should display the item if the current user does not have access to the item.
If set to Yes, the item is displayed disabled.If set to No, the item is hidden completely.
Note: Roles assigned to an item are highlighted. All others are displayed as usual. To assign the same roles to many items, select the items first by “Shift-clicking” or “Control-clicking” in the Menu Editor or Object Navigator, then select the roles through the Menu Item Roles property.
For additional information on how to manipulate Oracle server roles at run time, see Appendix I, “Using Oracle Server Roles at Run Time.”
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......................................................................................................................................................Lesson 2: Managing Menu Modules
Copyright Oracle Corporation, 2001. All rights reserved.®
Summary
In this lesson, you should have learned to:
• Exploit Menu Built-ins
• Include PL/SQL in menu items
• Implement menu security
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......................................................................................................................................................Summary
Summary
PL/SQL in Menu Item Commands• Typical PL/SQL uses
• Restrictions for PL/SQL in menu item commands
Built-ins for Use with Menu Modules• Showing and hiding the current menu:
- HIDE_MENU
- REPLACE_MENU
- SHOW_MENU
- MENU_REDISPLAY
• Getting and setting menu properties:
- FIND_MENU_ITEM
- GET_MENU_ITEM_PROPERTY
- SET_MENU_ITEM_PROPERTY
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......................................................................................................................................................Lesson 2: Managing Menu Modules
Instructor NoteThe practice overview in this lesson and the ones that follow are provided only as guides. Develop the practice with the level of detail appropriate for the students. This lab uses a lot of PL/SQL code. Because this is not a coding course, we provide the code. Take time to explain this practice so that students understand the code that they will import.
Copyright Oracle Corporation, 2001. All rights reserved.®
Practice 2 Overview
This practice covers the following topics:
• Enhancing the menu with a checkmenu item
• Synchronizing the menu Display_Helpitem with the form Help button
• Hiding irrelevant menu itemsaccording to form context
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......................................................................................................................................................Practice Overview: Lesson 2
Practice Overview: Lesson 2This practice guides you through enhancing custom menus for the ORDERS and CUSTOMERS forms.
Practice Contents• Add a check menu item.
• Enhance the menu so that the Display Help menu item is synchronized with the ORDERS Help button. If the Help button is enabled, a checkmark should appear next to the Display Help menu item.
• For the CUSTOMERS form, hide the menu items that are not relevant.
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......................................................................................................................................................Lesson 2: Managing Menu Modules
Practice 2 1 Define a check menu item.
a Open your M_SUMMIT menu module and add a new menu item to the Sort By menu; name it Display_Help.
b If Display_Help is selected, enable the ORDERS form toolbar HELP button and set the toolbar canvas background color to grey.
If Display_Help is not selected, disable the ORDERS form toolbar HELP button and set the toolbar canvas background color to red.
You can import the code from the pr2_1.txt file.
c Save and compile the menu module.
d Deploy your ORDERS form on the Web to test your menu.
2 Synchronize the menu module with the form.
a Write startup code for your M_SUMMIT menu module that synchronizes the Display_Help menu item with the toolbar HELP button. You can import the code from the pr2_2.txt file.
b Save and compile your menu module.
c Deploy your ORDERS form on the Web to test your menu.
3 Attach your M_SUMMIT menu to your CUSTOMERS form. The menu item Sort_By is not relevant, and should not be visible to the user.
a Attach the menu module to your CUSTOMERS form.
b Modify the startup code of the M_SUMMIT menu module to hide the SORT_BY menu when the CUSTOMERS form is opened. You can import the code from the pr2_3.txt file to replace the existing code. You may need to change the code to conform to the exact names you gave to the Main Menu and its menu items. Also, be sure the When-Button-Pressed trigger on the Orders button refers to your Orders form.
c Save and compile the menu module.
d Deploy your CUSTOMERS form to the Web and test your application. Execute a Query and click the Orders button to move to the ORDERS form. Note that the Sort_By menu item is hidden when the CUSTOMERS form is current, and is visible when the ORDERS form is current.
4 With both the ORDERS and CUSTOMERS form modules, restore the default menu, (DEFAULT&SMARTBAR).
Menu Label Menu Item Type Command Type
Display Help Check PL/SQL
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......................................................................................................................................................Lesson 3: Programming Function Keys
Instructor NoteTopic TimingLecture 30 minutes
Practice 30 minutes
Total 60 minutes
Copyright Oracle Corporation, 2001. All rights reserved.®
Objectives
After completing this lesson, you shouldbe able to do the following:
• Define key triggers and their uses
• Program function keys
• Describe the characteristics of key triggers
• Classify key triggers
• Associate function keys with interface controls
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......................................................................................................................................................Introduction
Introduction
OverviewForm Builder enables you to redefine the actions of function keys. This lesson shows you how to create key triggers to either intercept, or supplement, the usual function key behavior with which your users navigate the Oracle Forms Developer application.
ObjectivesAfter completing this lesson, you should be able to do the following:
• Define key triggers and their uses
• Program function keys
• Classify key triggers
• Associate function keys with interface controls
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......................................................................................................................................................Lesson 3: Programming Function Keys
Copyright Oracle Corporation, 2001. All rights reserved.®
Key Triggers
What is a key trigger?
Example:
Using Key-Exit, display an alert and exit theapplication if the user selects the “Yes” button.
SET_ALERT_PROPERTY(′question_alert′, ALERT_MESSAGE_TEXT,′Do you really want to leave the form? ′);
IF SHOW_ALERT(′question_alert′) = ALERT_BUTTON1 THEN EXIT_FORM; -- default functionality
END IF;
SET_ALERT_PROPERTY(′question_alert′, ALERT_MESSAGE_TEXT,′Do you really want to leave the form? ′);
IF SHOW_ALERT(′question_alert′) = ALERT_BUTTON1 THEN EXIT_FORM; -- default functionality
END IF;
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......................................................................................................................................................Key Triggers
Key TriggersIf you press a function key, Forms usually performs the default function associated with that key. You can modify the standard functionality of a function key by defining a key trigger for that function key.
What Is a Key Trigger?A key trigger, like any other trigger, is a subprogram that is executed when a certain event occurs. In the case of a key trigger, the event is pressing the function key for which the trigger is defined. The trigger is usually named after the event that causes it to fire. When the key trigger is defined for a function key, the usual functionality of the key is replaced by the PL/SQL text of the trigger. In this respect, key triggers resemble “on” triggers.
ExampleThe form level Key-Exit trigger below displays an alert asking the end user if he or she wants to leave the form.
SET_ALERT_PROPERTY(’question_alert’, ALERT_MESSAGE_TEXT, ’Do you really want to leave the form?’);
IF SHOW_ALERT(’question_alert’) = ALERT_BUTTON1 THEN
EXIT_FORM; -- default functionality
END IF;
Note: If you also want to execute the default functionality of the function key, you must ensure that the key trigger includes the built-in function associated with the key.
ExampleThe following form-level Key-Menu trigger disables [Block Menu] for a form.
BEGIN
NULL;
END;
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......................................................................................................................................................Lesson 3: Programming Function Keys
Instructor NoteDemonstration: Use Orders2.fmb to demonstrate changing properties for the Key-Duprec trigger at the form level.
Copyright Oracle Corporation, 2001. All rights reserved.®
Key Trigger Propertiesand PL/SQL Editor
Display in “Keyboard Help”“Keyboard Help” Text
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......................................................................................................................................................Defining Key Triggers
Defining Key TriggersYou define key triggers in the same way that you define any other trigger. However, the following two properties in the Property Palette for triggers only apply to key triggers.
Property DescriptionDisplay in Keyboard Help Specifies whether a key trigger description is displayed in the
run-time Keys Help windowKeyboard Help Text Specifies the text that is displayed in the run time Keys Help
window if the display in the Keyboard Help property is set to Yes (If you want the default description to be displayed, leave this property blank.)
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......................................................................................................................................................Lesson 3: Programming Function Keys
Copyright Oracle Corporation, 2001. All rights reserved.®
Characteristics of Key Triggers
• You cannot redefine all function keys withkey triggers.
• Key triggers are defined at all three levels.
• A key trigger can contain SELECT statements andall built-ins.
• Key triggers can fire in Enter Query mode.
Copyright Oracle Corporation, 2001. All rights reserved.®
Characteristics of Key Triggers
Function Key
[Accept]
[Clear Form]
[Create Record]
[Delete Record]
Key Trigger
Key-Commit
Key-Clrfrm
Key-Crerec
Key-Delrec
Built-in
COMMIT_FORM
CLEAR_FORM
CREATE_RECORD
DELETE_RECORD
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......................................................................................................................................................Characteristics of Key Triggers
Characteristics of Key Triggers
Rules of Key Triggers• You cannot redefine all function keys with key triggers. Some keys are
handled by the terminal or window interface manager rather than by Forms. Examples of such static function keys are [Clear Item], [Left], [Right], and [Toggle Insert/Replace].
• You can define key triggers at all three levels: form, block, and item.
• You can use SELECT statements, restricted built-in functions, and unrestricted built-ins.
• Key triggers can fire in Enter Query mode.
Note: You cannot use all built-ins in Enter Query mode.
If you do not redefine a function key, a built-in function performs its default functionality when you press the key. Therefore, in most cases, a built-in function and a key trigger are associated with a function key. The following table gives some examples of this association.
Function Keys, Their Associated Built-in Functions, and Key Triggers
Note: This list is incomplete.
Function Key Built-in Function Key Trigger[Accept] COMMIT_FORM Key-Commit[Create Record] CREATE_RECORD Key-Crerec[Delete Record] DELETE_RECORD Key-Delrec[Duplicate Record] DUPLICATE_RECORD Key-Duprec[Enter Query] ENTER_QUERY Key-Entqry[Execute Query] EXECUTE_QUERY Key-Exeqry[List] LIST_VALUES Key-Listval[Next Item] NEXT_ITEM Key-Next-Item[Down] DOWN Key-Down[Next Record] NEXT_RECORD Key-Nxtrec[Exit] EXIT_FORM Key-Exit
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......................................................................................................................................................Lesson 3: Programming Function Keys
Technical NoteThe function keys Fn do not necessarily map to F1, F2, F3, and so on.
Copyright Oracle Corporation, 2001. All rights reserved.®
Classification of Key Triggers
• Function key triggers
• Key-Fn triggers andOracle Terminal
• Key-Others triggers
• Key mapping forWeb-deployed formsis different toClient Server
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......................................................................................................................................................Classification of Key Triggers
Classification of Key TriggersYou can distinguish among different types of key triggers. Learning these classifications will help you understand when to use key triggers.
Types of Key Triggers
Key MappingKey mapping is defined by a platform specific resource file. The key definition file for the Microsoft Windows platform is FMRUSW.RES. You should use Oracle Terminal to edit Client Server resource files. For Web applications, you can edit the Java resource file, FMRWEB.RES, with any suitable operating system editor.
Category DescriptionFunction key triggers Key triggers that are associated with existing function keys
(They fire when the associated function key is pressed.)Key-Fn triggers Key triggers that are associated with the logical Runtime keys
F0 through F9 (Before you can use these Key triggers, you or the DBA must map these logical keys to physical keys or key sequences. They fire when the associated physical key or key sequence is pressed.)
Key-Others trigger A key trigger that is associated with all keys that can have key triggers associated with them, but are not currently redefined by a function key trigger at any level
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......................................................................................................................................................Lesson 3: Programming Function Keys
Technical NoteSince mouse-event key triggers are not executed when the mouse is used to initiate window interaction, you should not place code that needs to be executed every time the window interaction occurs in a mouse-event key trigger.
Instructor NoteDemonstration:
• Use Orders2.fmb to demonstrate preventing duplication of the primary key by using the Key-Duprec trigger.
• Use the same demonstration to illustrate a call of a customized list of values (LOV) form instead of the native Forms LOV, using Key-Listval. To do this, click the product LOV button. Do not explain in detail the code associated with this button; it is covered in a later lesson.
Copyright Oracle Corporation, 2001. All rights reserved.®
Classification of Key Triggers
Mouse-event key triggers:
• Key-Next-Item
• Key-Prev-Item
• Key-Nxtrec
• Key-Prvrec
• Key-Up
• Key-Down
• Key-Scrup
• Key-Scrdown
• Key-Nxtblk
• Key-Prvblk
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......................................................................................................................................................Classification of Key Triggers
What Are Mouse-Event Key Triggers?Mouse-event key triggers are function key triggers whose associated default functionality can also be activated directly with the mouse.
Examples• The Key-Nxtblk trigger is a mouse-event key trigger, because the
NEXT_BLOCK functionality can also be activated using the mouse by clicking in the next block. In this case, a possible Key-Nxtblk trigger will not fire.
• The Key-Exeqry trigger is not a mouse-event key trigger, because the EXECUTE_QUERY functionality cannot be activated by simply clicking the mouse. It can be activated by the mouse only if a trigger is defined to fire as a result of the mouse action.
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......................................................................................................................................................Lesson 3: Programming Function Keys
Copyright Oracle Corporation, 2001. All rights reserved.®
Using Key Triggers
• Adjust user interface
• Disable a (set of) function keys
• Replace or extend functionality of function keys
• Add additional function keys
• Be careful with Key-Others
• Do not use for validation
Copyright Oracle Corporation, 2001. All rights reserved.®
Specific Key Trigger Uses
• Call an LOV form
• Check for detail records before deleting amaster record
• Prevent duplication of the primary key
• Adjust toolbar buttons for Enter Query mode
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......................................................................................................................................................Using Key Triggers
Using Key TriggersYou should use key triggers sparingly. Often you must define many key triggers to trap a certain event completely. Mouse-event key triggers can be circumvented with the mouse. Use key triggers only if you want to adjust the default user interface.
Common Uses• Disable function keys
• Replace or extend the default functionality of function keys
• Add additional keys for custom functions using Key-Fn triggers
• Disable a set of function keys using Key-Others
When Not to Use Key Triggers• To perform validation; use validation triggers instead
• To amend navigation; use navigational triggers instead
• To perform data manipulation; use transactional triggers instead
Specific Key Trigger Uses• Call a list of values (LOV) form instead of the native Forms LOV, using
Key-Listval
• Check if detail records exist before deleting a master record if the master block and detail block are in separate forms, using Key-Delrec
• Prevent duplication of the primary key when duplicating a record, using Key-Duprec
• Adjust behavior of toolbar buttons when Enter Query mode is entered or left, using Key-Entqry
Technical NoteTo determine if a Key-Others trigger applies to a function key, Forms looks for associated key triggers at all levels. For example, if you define the Key-Others trigger at the block level, it will not fire for those function keys for which a key trigger is defined at the form level.
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......................................................................................................................................................Lesson 3: Programming Function Keys
Instructor NoteDemonstration: Use Orders2.fmb to demonstrate code for the CONTROL.EXIT_BUTTON button. Also show the Key-Exit trigger at form level.
Copyright Oracle Corporation, 2001. All rights reserved.®
Association with OtherInterface Controls
Syntax: DO_KEY(built_in_name)
Example: To customize actions when a user
exits the form with [Exit Form], a button,
or a menu item:
1. Key-Exit
-- custom actions when user tries to exitEXIT_FORM;...
-- custom actions when user tries to exitEXIT_FORM;...
Copyright Oracle Corporation, 2001. All rights reserved.®
Association with OtherInterface Controls
• DO_KEY(’Key-Exit’) gives run-timeerror
• Corresponding interface controldescriptions
DO_KEY(’EXIT_FORM’);DO_KEY(’EXIT_FORM’);
2. In When-Button-Pressed and Menu item code:
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......................................................................................................................................................Association with Other Interface Controls
Association with Other Interface ControlsYou can often activate the same functionality in various ways, such as by pressing a function key, choosing a menu item, clicking a button, or performing direct manipulation with the mouse. In this case, you want to specify that the PL/SQL code be executed only once. You can use the built-in function DO_KEY to accomplish this.
What Is DO_KEY?DO_KEY is a built-in function that executes the key trigger that corresponds to the built-in subprogram specified as its parameter. If no key trigger is defined, the specified built-in is executed.
SyntaxDO_KEY(built_in_name)
ExampleExit a Form by clicking [Exit Form] or an Exit button, or by choosing a menu item.
1 Define a Key-Exit trigger at form level.
2 Call DO_KEY by using:
a The When-Button-Pressed trigger on the associated Exit button
b The menu-item code for the menu item that exits the form using DO_KEY(’EXIT_FORM’);
Interface Control DescriptionsIf the same functionality is activated by various interface controls, you should also make sure that the controls have the same descriptions.
Interface Control Property for Description Changeable at Run Time?Function key Show keys description NoMenu item Menu-item label YesButton Button label YesMouse event Not applicable Not applicable
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......................................................................................................................................................Lesson 3: Programming Function Keys
Copyright Oracle Corporation, 2001. All rights reserved.®
Summary
In this lesson, you should have learned to:
• Define key triggers in order to:
– Enhance keyboard functionality
– Replace keyboard key
• Provide consistent functionality betweenFunction keys, buttons, menu items, andmouse events
• Display text in Keyboard Help
• Define Key-Fn, Key-Others, and mouse-event keytriggers
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......................................................................................................................................................Summary
Summary
Understanding Key Triggers• They fire when the associated function key is pressed.
• They are defined like any other trigger.
• Special properties are Display in Keyboard Help and Keyboard Help Text.
Classification of Key Triggers• Function key triggers
• Key-Fn triggers
• Key-Others
• Mouse-event key triggers
Uses of Key Triggers• Disable function keys
• Replace or extend default behavior of function keys
• Add function keys using Key-Fn triggers
• Adjust set of function keys using Key-Others
Association with Other Interface Controls• Function keys, buttons, menu items, mouse events
• Keys description, button label, menu-item label
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......................................................................................................................................................Lesson 3: Programming Function Keys
Instructor NoteThe practices include the use of CALL_FORM. Explain to the students that is an alternative to OPEN_FORM, and will be covered in a later lesson.
Copyright Oracle Corporation, 2001. All rights reserved.®
Practice 3 Overview
This practice covers the following topics:
• Enforcing consistent form run timefunctionality by redefining [Exit Form]
• Changing the behavior of function keys byreplacing [Enter Query] with a custom query form
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......................................................................................................................................................Practice Overview: Lesson 3
Practice Overview: Lesson 3This practice guides you though redefining function keys with key triggers.
Practice Contents• Use a key trigger to redefine [Exit Form] to provide consistent behavior
between Menu and form modules.
• Disable [Enter Query] mode, and replace with a custom query form.
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......................................................................................................................................................Lesson 3: Programming Function Keys
Practice 3 1 Maintain consistent functionality in your form module by using key
triggers. Define a key trigger in your ORDERS form to give users consistent functionality whenever they exit the form, either using the menu or when the CONTROL.EXIT_BUTTON button is pressed.
a Redefine [Exit Form] in your ORDERS form so that an alert message is displayed to users before allowing them to exit the form.
b Amend the entry in Keyboard Help to “Exit Orders” for the key trigger.
c Save and compile your form. Deploy your form to the Web to test.
d Customize the Alert Text message in your key trigger and ensure that it is displayed whenever the user exits the form using the EXIT_BUTTON on the Control block.
e Save and compile your form module. Deploy to the Web and test your form.
If you have time2 Disable [Enter query] in your CUSTOMERS form by creating an
appropriate key trigger. Replace [Enter Query] functionality with a call to the customized query form CUSTQUERY. This form allows the user to select a CUSTOMER ID, a CUSTOMER NAME, or a SALES REP ID. The user selections are returned to your CUSTOMER form using global variables.
a Add the following code to your key trigger:call_form(’custquery’,no_hide);
execute_query;
b The CUSTQUERY form will return three values, held in global variables. The contents should be passed to your CUSTOMERS form to allow the user to execute a restricted query. Use the following global variables::global.custid;
:global.custname;
:global.repid;
c Define the global variables in your CUSTOMERS form to ensure that the user can perform unrestricted queries.
d Save and compile your CUSTOMER form. Deploy your form to the Web to test.
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......................................................................................................................................................Lesson 4: Responding to Mouse Events
Instructor NoteTopic TimingLecture 30 minutes
Practice 20 minutes
Total 50 minutes
Copyright Oracle Corporation, 2001. All rights reserved.®
Objectives
After completing this lesson, you should be able dothe following:
• Define mouse events
• Cause a form module to respond to mousemovement
• Cause a form module to respond to mousebutton actions
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......................................................................................................................................................Introduction
Introduction
OverviewThe keyboard, menu, and mouse are the operator’s tools for interacting with the Forms application. This lesson demonstrates how to write an application that responds to mouse events.
ObjectivesAfter completing this lesson, you should be able to do the following:
• Define mouse events
• Cause a form module to respond to mouse movement
• Cause a form module to respond to mouse button actions
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......................................................................................................................................................Lesson 4: Responding to Mouse Events
Instructor NoteUse mousecursor.fmb to demonstrate the mouse cursor styles. Remind delegates to return the cursor style to DEFAULT after trigger failure.
Copyright Oracle Corporation, 2001. All rights reserved.®
Mouse Events
• Point at which processing can be influenced
• Identified by:
– Mouse movement
– Mouse button action
Copyright Oracle Corporation, 2001. All rights reserved.®
Mouse Cursor Style
To change the cursor style dynamically:
DEFAULT
BUSY
CROSSHAIR
HELP
INSERTION
GUI-specific arrow symbol
GUI-specific busy symbol
GUI-specific crosshair symbol
GUI-specific help symbol
GUI-specific insertion symbol
SET_APPLICATION_PROPERTY(CURSOR_STYLE,
′value′);
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......................................................................................................................................................What Are Mouse Events?
What Are Mouse Events?An event is a point at which Forms processing can be influenced. Every object can have processing events with which you can associate PL/SQL code (triggers).
A mouse event is an event that is identified by a mouse movement or a mouse button action.
The Seven Mouse EventsThe Forms mouse events is divided in two groups: mouse movement events and mouse button action events.
The mouse movement events are:
• Entry into an item or canvas
• Exit from an item or canvas
• General movement
The events that correspond to mouse button actions are:
• Click
• Double-click
• Up
• Down
Mouse Cursor StyleForm Builder allows you to change dynamically the cursor style. Use thefollowing built-in to do it:
SET_APPLICATION_PROPERTY( CURSOR_STYLE, ’ value’);
The valid settings for the cursor style property are:
• BUSY
• CROSSHAIR
• DEFAULT
• HELP
• INSERTION
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......................................................................................................................................................Lesson 4: Responding to Mouse Events
Instructor NoteMouse movement and button trigger functionality in Web-deployed forms can be provided by creating appropriate JavaBeans. Deployment of these JavaBeans is covered in a later lesson; for the creation of JavaBeans, students should be referred to an appropriate Java tool, such as Oracle JDeveloper.
Demonstration If they do not already exist, create and populate the EMP and DEPT tables by running the UTLSAMPLE.SQL script.
Use mousewinner.fmb to demonstrate the operation of the When-Mouse-Enter trigger.
Use mousevariables.fmb to demonstrate all the mouse triggers and system variables.
Copyright Oracle Corporation, 2001. All rights reserved.®
Mouse Movement Triggers
When-Mouse-Enter
When-Mouse-Leave
When-Mouse-Move
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......................................................................................................................................................Responding to Mouse Movement
Responding to Mouse MovementYou can initiate an action whenever mouse movement occurs by defining the mouse movement triggers.
The Three Mouse Movement Triggers
Uses of the Mouse Movement Triggers• Use When-Mouse-Move in conjunction with the
SYSTEM.MOUSE_X_POS and SYSTEM.MOUSE_Y_POS system variables to return the exact position of the mouse within an item.
• Use When-Mouse-Leave to update an item value without causing the cursor to navigate out of the current item
Web Design TipIf you define mouse movement triggers in client server applications, this may adversely affect the performance of your form. This is because these triggers have the potential to fire frequently. For this reason, you should use them sparingly; in Web-deployed forms these triggers are disabled.
Trigger UseWhen-Mouse-Enter Fires when the user moves the mouse into an
item or canvas-viewWhen-Mouse-Leave Fires when the user moves the mouse out of
an item or canvas-viewWhen-Mouse-Move Fires when the user moves the mouse within
an item or canvas-view
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......................................................................................................................................................Lesson 4: Responding to Mouse Events
Technical NoteThe SYSTEM.MOUSE_FORM system variable is NULL if the platform is not a GUI platform.
Instructor NoteDemonstration: Use mousevariables.fmb to demonstrate all the mouse triggers and system variables.
1 MOUSE_FORM 5 MOUSE_RECORD_OFFSET
2 MOUSE_CANVAS 6 MOUSE_X_POS
3 MOUSE_ITEM 7 MOUSE_Y_POS
4 MOUSE_RECORD
Copyright Oracle Corporation, 2001. All rights reserved.®
Mouse Position System Variables
1
5
6
72
3
4
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......................................................................................................................................................Responding to Mouse Movement
The Mouse Position System VariablesUse the following system variables to determine when the mouse has moved, where it has moved from, and where it has moved to.
Variable UseSYSTEM.MOUSE_FORM Identifies the form module that the mouse is
currently inSYSTEM.MOUSE_CANVAS Identifies the canvas that the mouse is currently
onSYSTEM.MOUSE_ITEM Identifies the item that the mouse is currently inSYSTEM.MOUSE_RECORD Identifies the record number that the mouse is
currently inSYSTEM.MOUSE_RECORD_OFFSET Identifies the number of the record that the mouse
is currently in, relative to the first visible record; uses a 1-based index
SYSTEM.MOUSE_X_POS Identifies the x coordinate of the mouse’s current position (If the mouse is positioned on a canvas, the x coordinate is measured relative to the top left corner of the canvas. If the mouse is in an item, the x coordinate is measured relative to the top left corner of the item.)
SYSTEM.MOUSE_Y_POS Identifies the y coordinate of the mouse’s current position (If the mouse is positioned on a canvas, the y coordinate is measured relative to the top left corner of the canvas. If the mouse is in an item, the y coordinate is measured relative to the top left corner of the item.)
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......................................................................................................................................................Lesson 4: Responding to Mouse Events
Technical NoteClick and double-click work only if the mouse stays on the item (or canvas) throughout the down-up action.
Copyright Oracle Corporation, 2001. All rights reserved.®
Mouse Button Action Triggers
When-Mouse-Down
When-Mouse-Up
When-Mouse-Click
When-Mouse-Doubleclick
click
click click
Copyright Oracle Corporation, 2001. All rights reserved.®
Mouse Event Trigger Sequence
1. When-Mouse-Down
2. When-Mouse-Up
3. When-Mouse-Click
4. When-Mouse-Down
5. When-Mouse-Up
6. When-Mouse-Doubleclick
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......................................................................................................................................................Responding to Mouse Button Actions
Responding to Mouse Button ActionsYou can initiate an action whenever a mouse button action occurs by defining the mouse button action triggers.
The Mouse Button Action Triggers
Firing Sequence for Mouse Button Action TriggersWhen you double-click an item or canvas, you are potentially causing the following triggers to fire in the order in which they are listed. Similarly, when you click an item or canvas, the triggers that precede the When-Mouse-Click trigger will fire.
• When-Mouse-Down
• When-Mouse-Up
• When-Mouse-Click
• When-Mouse-Down
• When-Mouse-Up
• When-Mouse-Doubleclick
Web Design TipWhen any mouse button action is initiated in a Web-deployed form, the Java user interface refers to Forms Services to identify the appropriate mouse button trigger. Even though you may not have defined the relevant mouse button trigger, the user interface will generate this event if you have defined at least one mouse button trigger in your form. You should therefore restrict use of mouse button triggers.
Trigger UseWhen-Mouse-Down Initiates an action when the user presses the
mouse button down while the mouse is point-ing to an item or a canvas
When-Mouse-Up Initiates an action when the user presses and releases the mouse button while the mouse is pointing to an item or a canvas
When-Mouse-Click Initiates an action when the user clicks on an item or canvas
When-Mouse-Doubleclick Initiates an action when the user double-clicks an item or canvas
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......................................................................................................................................................Lesson 4: Responding to Mouse Events
Copyright Oracle Corporation, 2001. All rights reserved.®
Mouse Button ActionSystem Variables
SYSTEM.MOUSE_BUTTON_PRESSED
SYSTEM.MOUSE_BUTTON_MODIFIERS
AltCtrl
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......................................................................................................................................................Responding to Mouse Button Actions
The Mouse Button System VariablesUse the following system variables to determine which mouse button was pressed and which special key, if any, was used.
If the operator holds down the [Ctrl] and [Shift] keys while pressing the mouse button, SYSTEM.MOUSE_BUTTON_MODIFIERS contains the value Shift+Control+.
Variable UseSYSTEM.MOUSE_BUTTON_PRESSED Identifies which mouse button was pressed
(values of 1–3, where 1 is the left mouse button)
SYSTEM.MOUSE_BUTTON_MODIFIERS Identifies which special key was pressed to modify the usual mouse button action (possible values are Shift+, Caps Lock+, Control+, Alt+, Command+, Super+, and Hyper+)
4-14 Oracle iDS Forms: Build Internet Applications II......................................................................................................................................................
......................................................................................................................................................Lesson 4: Responding to Mouse Events
Copyright Oracle Corporation, 2001. All rights reserved.®
Summary
In this lesson, you should have learned how to:
• Respond to mouse movement
– Mouse position system variables
– Mouse movement triggers
• Respond to mouse button actions
– Mouse button system variables
– Mouse button triggers
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......................................................................................................................................................Summary
SummaryIn this lesson, you saw how to write an application that responds to mouse events.
Mouse Events • Entry to a canvas or an item
• Exit from a canvas or an item
• Move the cursor
• Click
• Double-click
• Up
• Down
• Responding to mouse movement
• Mouse position system variables
Mouse Movement Triggers• When-Mouse-Enter
• When-Mouse-Leave
• When-Mouse-Move
Responding to Mouse Button Actions• Mouse button system variables
• Mouse button triggers
- When-Mouse-Click
- When-Mouse-Doubleclick
- When-Mouse-Up
- When-Mouse-Down
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......................................................................................................................................................Lesson 4: Responding to Mouse Events
Copyright Oracle Corporation, 2001. All rights reserved.®
Practice 4 Overview
This practice covers the following topics:
• Invoke an editor when the operatordouble-clicks an item
• Redefine the mouse cursor style accordingto context
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......................................................................................................................................................Practice Overview: Lesson 4
Practice Overview: Lesson 4This practice guides you through using mouse-event triggers and mouse system variables.
Practice Contents• Define a mouse-event trigger to invoke an editor on the
S_CUSTOMER.COMMENTS item.
• Modify the mouse cursor style whenever the ORDERS Help canvas is displayed.
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......................................................................................................................................................Lesson 4: Responding to Mouse Events
Practice 4 In this practice, you provide additional functionality in your forms by defining mouse event triggers.
1 In your CUSTOMERS form, define a mouse event trigger on S_CUSTOMER.COMMENTS that invokes the item’s editor when the user double-clicks the item.
2 In your ORDERS form change the mouse cursor symbol to “busy” while the HELP canvas is displayed.
a Ensure that the default symbol is restored whenever the user hides the HELP canvas.
b The user can close the HELP canvas without pressing the HIDEHELP button, by navigating to an item in another block. How can you ensure that the mouse cursor is always restored?
c Save and compile your form modules. Deploy your forms to the Web to test. You can call the ORDERS form from your CUSTOMERS form.
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......................................................................................................................................................Lesson 5: Controlling Windows and Canvases Programmatically
Instructor NoteTopic TimingLecture 45 minutes
Practice 35 minutes
Total 80 minutes
Copyright Oracle Corporation, 2001. All rights reserved.®
Objectives
After completing this lesson, you shouldbe able to do the following:
• Display a form document in multiplewindows
• Write code to interact with windows
• Manipulate windows programmatically
• Manipulate canvas views programmatically
• Control windows and canvases withWeb-deployed forms
• Display large data blocks in a window
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......................................................................................................................................................Introduction
Introduction
OverviewYou should already be familiar with setting window and canvas properties at design time. This lesson covers the triggers and built-ins that you can use to manage the properties and behavior of windows and canvases at run time.
ObjectivesAfter completing this lesson, you should be able to do the following:
• Display a form module in multiple windows
• Write code to interact with windows
• Manipulate windows programmatically
• Manipulate canvas views programmatically
• Control windows and canvases with Web-deployed forms
• Display large data blocks in a window
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......................................................................................................................................................Lesson 5: Controlling Windows and Canvases Programmatically
Copyright Oracle Corporation, 2001. All rights reserved.®
Trigger
When-Window-Activated
When-Window-Deactivated
When-Window-Closed
When-Window-Resized
Using Window-Interaction Triggers
System Variable
:SYSTEM.EVENT_WINDOW
Use
Enforces navigation
Deactivates a window
Closes a window
Maintains visualstandards
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......................................................................................................................................................Using Window-Interaction Triggers
Using Window-Interaction TriggersYou can use four window-interaction triggers to provide extra functionality whenever a user interacts with a window. These triggers should be defined at the form level.
The common uses for those triggers are the following:
Keeping Track of the Triggered WindowThe SYSTEM.EVENT_WINDOW system variable contains the name of the last window for which a window-interaction trigger fired. You can use this system variable to perform different actions for different windows in your window-interaction triggers.
Note: Help with triggers is available by pressing [Ctrl] + [H] and selecting PL/SQL Reference - Triggers.
Trigger CharacteristicWhen-Window-Activated Fires when a window is made the active window (Note
that window activation can occur independently of navi-gation.)
When-Window-Deactivated Fires when a user deactivates a window by setting the input focus to another window
When-Window-Closed Fires when a user closes a window by using a window-manager-specific Close command
When-Window-Resized Fires when a window is resized, either by the user or through a trigger (It also fires at form startup, but not when a window is made into an icon.)
Trigger UseWhen-Window-Activated Captures initial settings of window properties; enforces
navigation to a particular item whenever the window is activated
When-Window-Deactivated Deactivates a windowWhen-Window-Closed Closes a window programmaticallyWhen-Window-Resized Maintains visual standards; captures window properties
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......................................................................................................................................................Lesson 5: Controlling Windows and Canvases Programmatically
Technical NoteIn Microsoft Windows, you can reference the multiple document interface (MDI) application window with the FORMS_MDI_WINDOW constant. FORMS_MDI_WINDOW is used with certain built-in functions and procedures that relate to windows.
In Web-deployed forms, you can obtain similar functionality by settingthe Forms Applet WIDTH and HEIGHT parameters in the base HTML page.Definition of these Form Applet parameters is covered later in this course.
Copyright Oracle Corporation, 2001. All rights reserved.®
Built-ins for ManipulatingWindows
• FIND_WINDOW
• GET_WINDOW_PROPERTY
• SET_WINDOW_PROPERTY
• HIDE_WINDOW
• SHOW_WINDOW
• MOVE_WINDOW
• RESIZE_WINDOW
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......................................................................................................................................................Built-ins for Manipulating Windows
Built-ins for Manipulating Windows
Built-in Description
FIND_WINDOW Returns the internal window ID (of data type WINDOW) of a window with the given name
GET_WINDOW_PROPERTY Returns the current value of the specified window property for the given window
SET_WINDOW_PROPERTY Sets the specified window property for the given window to a specified value
HIDE_WINDOW Hides the window
SHOW_WINDOW Makes the window visible at the current or specified display position
MOVE_WINDOW Moves the window to the location specified by the given coordinates
RESIZE_WINDOW Changes the window to the specified width and height
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......................................................................................................................................................Lesson 5: Controlling Windows and Canvases Programmatically
Technical NoteREPLACE_CONTENT_VIEW does not hide the stacked canvas already displayed in the window. In contrast SHOW_VIEW and SET_VIEW_PROPERTY will display the given canvas in front of any stacked canvas, if the canvas Visible property is set to true.
Instructor NotePoint out that the GET_ built-ins are the most important ones when writing generic code.
Use tab_page.fmb to demonstrate:
• The tab canvas system variables. Click any tab page
• How to enforce navigation when a user selects a tab page
• Clicking the TopMost Tab Page button to illustrate the TOPMOST_TAB_PAGE argument
You can run this demonstration on the Web from winmenu.fmb.
Copyright Oracle Corporation, 2001. All rights reserved.®
Built-ins for ManipulatingCanvases
• FIND_CANVAS
• GET_CANVAS_PROPERTY
• SET_CANVAS_PROPERTY
• FIND_VIEW
• GET_VIEW_PROPERTY
• SET_VIEW_PROPERTY
• HIDE_VIEW
• SHOW_VIEW
• REPLACE_CONTENT_VIEW
• SCROLL_VIEW
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......................................................................................................................................................Built-ins for Manipulating Canvases
Built-ins for Manipulating Canvases
Built-in DescriptionFIND_CANVAS Returns the internal canvas ID (CANVAS data type)
of a canvas with the given nameGET_CANVAS_PROPERTY Returns the current value of the specified canvas prop-
erty for the given canvasSET_CANVAS_PROPERTY Sets the specified canvas property for the given canvas
to a specified valueFIND_VIEW Returns the internal view ID (VIEWPORT data
type) of a canvas with the given nameGET_VIEW_PROPERTY Returns the current value of the specified view prop-
erty for the canvasSET_VIEW_PROPERTY Sets the specified view property for the given canvas
to a specified valueHIDE_VIEW Hides the canvasSHOW_VIEW Makes the given canvas visible at the current display
positionREPLACE_CONTENT_VIEW Replaces the content canvas currently displayed in the
window with the specified content canvasSCROLL_VIEW Moves the view of a given canvas to a different posi-
tion on its canvas (does not move the window to a different position on the screen)
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......................................................................................................................................................Lesson 5: Controlling Windows and Canvases Programmatically
Instructor NoteThe When-Tab-Page-Changed trigger does not fire if the end user presses [Next Item] + [Tab] to navigate from one field to another in the same block but on different tab pages.
Copyright Oracle Corporation, 2001. All rights reserved.®
Working with Tab-StyleCanvases
Page 1 Page 3Page 2click
• Uses either function key
• Next tab Page
• Previous Tab page
The When-Tab-Page-Changed trigger
fires when a user:
• Clicks a tab
Previous Tab Page
NextTab Page
Copyright Oracle Corporation, 2001. All rights reserved.®
Working with Tab-Style Canvases
Tab canvas system variables:
• :SYSTEM.TAB_NEW_PAGE
• :SYSTEM.TAB_PREVIOUS_PAGE
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......................................................................................................................................................Working with Tab-Style Canvases
Working with Tab-Style Canvases
When-Tab-Page-Changed TriggerThis form-level trigger fires when there is explicit item or mouse navigation from one tab page to another in a tab canvas; in other words, when the user clicks a tab or presses [Ctrl] + [PgUp] or [Ctrl] + [PgDown].
This trigger is very often used to perform actions when any tab page is changed during item or mouse navigation; for example, to enable or disable items or to set default or related item values.
Be aware that this trigger does not fire when the tab page is changed programmatically and does not fire with implicit navigation.
Tab Canvases System VariablesWithin the When-Tab-Page-Changed trigger, you can reference system variables to determine where you are coming from and going to.
• :SYSTEM.TAB_NEW_PAGE returns the name of the tab page to which you are going.
• :SYSTEM.TAB_PREVIOUS_PAGE returns the name of the tab page from which you are coming.
These system variables return only the page name, not the canvas name, so you must name all tab pages uniquely across the form if you need to be able to identify them programmatically.
Technical NoteWhen you are changing to another tab page, the cursor does not automatically move to a different item. To move the cursor you must include a GO_ITEM statement in the When-Tab-Page-Changed trigger. This is intended functionality to allow users to view other tab pages without navigating the cursor and therefore causing item navigation and validation (as previously mentioned).
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......................................................................................................................................................Lesson 5: Controlling Windows and Canvases Programmatically
Instructor NoteTOPMOST_TAB_PAGE returns only the tab page name, and not the canvas name. To set a property, you must concatenate the canvas name with the page name.
Copyright Oracle Corporation, 2001. All rights reserved.®
Working with Tab-StyleCanvases
• FIND_TAB_PAGE: Returns the tab page ID
• GET_TAB_PAGE_PROPERTY: Returnsthe tab page label or the tab page canvas
• SET_TAB_PAGE_PROPERTY: Enables changingof the tab page label
Copyright Oracle Corporation, 2001. All rights reserved.®
Other Arguments for CanvasBuilt-Ins
• Identify the topmost tab page
• Bring a tab page to the top programmatically
If GET_CANVAS_PROPERTY(’custab’,
TOPMOST_TAB_PAGE)= ’Billing’ then
SET_CANVAS_PROPERTY(’custab’,
TOPMOST_TAB_PAGE,
’Address’);
end if;
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......................................................................................................................................................Working with Tab-Style Canvases
Built-ins for Manipulating Tab-Style Canvases
Note: The tab page is named using the syntax “CanvasName.PageName.”
ExampleDECLARE
tp_id Tab_Page;
BEGIN
tp_id := Find_Tab_Page(’Canvas2.TabPage1’);
IF Get_Tab_Page_Property(tp_id, enabled) =’FALSE’ THEN
Set_Tab_Page_Property(tp_id, enabled, property_true);
END IF;
END;
Other Arguments for Canvas Built-InsIf you want to make a tab page the top-most on its underlying tab canvas, you can use the built-in procedure SET_CANVAS_PROPERTY and set the canvas property TOPMOST_TAB_PAGE. You can also get the top-most tab page by using the built-in function GET_CANVAS_PROPERTY.
GET_CANVAS_PROPERTY(‘canvas_name’, TOPMOST_TAB_PAGE)
SET_CANVAS_PROPERTY(‘canvas_name’, TOPMOST_TAB_PAGE, page_name)
In the preceding syntax example, page_name is either a constant, in single quotes, or a variable.
Built-in DescriptionFIND_TAB_PAGE Searches the list of tab pages in a given tab canvas and
returns a tab page ID when it finds a valid tab page with the given name (You must define a variable of type TAB_PAGE to accept the return value.)
GET_TAB_PAGE_PROPERTY Returns property values (CANVAS_NAME, ENABLED, LABEL, VISIBLE, VISUAL_ATTRIBUTE) for a specified tab page
SET_TAB_PAGE_PROPERTY Sets the tab page properties (ENABLED, LABEL, VISIBLE, VISUAL_ATTRIBUTE) of the specified tab canvas page
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......................................................................................................................................................Lesson 5: Controlling Windows and Canvases Programmatically
Copyright Oracle Corporation, 2001. All rights reserved.®
Block 3
Windows and Blocks
Block 1
Block 2
Cursorlocation
Nonactivewindow
Active window Window 1
Window 2
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......................................................................................................................................................Windows and Blocks
Windows and BlocksForm Builder processes many events based on blocks (and items), which can be completely independent of windows (and canvases). Keep in mind the following characteristics of windows and blocks.
Connection Between Windows and Blocks• A window can contain multiple canvases, and multiple items can be
located on a canvas.
• A block can contain multiple items, and an item is located on one and only one canvas (except for null canvas items).
• A window can contain multiple blocks, and a block can be located on several windows.
Note: In general, put blocks in separate windows. If blocks are closely related (through a foreign-key relationship), put them in the same window.
Window Activation and Block NavigationYou can use the When-Window-Activated trigger to activate another window automatically (see the Closing Windows example later in this lesson).
Transaction ManagementDuring commit processing, Forms processes all base table blocks insequential order. Therefore, transaction management is block-based rather than window-based. However, the user expects to interact with a form in a window-based manner.
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......................................................................................................................................................Lesson 5: Controlling Windows and Canvases Programmatically
Technical NoteYou can also maximize the client server MDI window application with the WINDOW_STATE command line parameter:
ifrun60.exe module=customer.fmx userid=my_name/my_password@my_database window_state=maximize
You can switch from the MDI to the SDI window application by using the USESDI command line parameter:
ifrun60.exe module=customer.fmx userid=my_name/my_password@my_database usesdi=yes
With SDI window applications, you must size form module windows to allow for the menu, menu toolbar, and console bar to display.
Instructor NoteDemonstration: Use window.fmb to demonstrate the two examples described above. Show the When-New-Form-Instance trigger, which includes the code for maximizing the MDI application window.
Show the GET_CURSOR_WINDOW program unit.
Copyright Oracle Corporation, 2001. All rights reserved.®
Manipulating Window PropertiesProgrammatically
Maximizing MDI application window
Locating the Cursor window
SET_WINDOW_PROPERTY (forms_mdi_window,
window_state, maximize);
SET_WINDOW_PROPERTY (forms_mdi_window,
window_state, maximize);
GET_VIEW_PROPERTY (GET_ITEM_PROPERTY(NAME_IN
(′system.cursor_item′), item_canvas), window_name);
GET_VIEW_PROPERTY (GET_ITEM_PROPERTY(NAME_IN
(′system.cursor_item′), item_canvas), window_name);
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......................................................................................................................................................Manipulating Window Properties Programmatically
Manipulating Window Properties ProgrammaticallyYou can use the window-interaction triggers and the built-ins for windows to manipulate your windows (and the MDI application window on Microsoft Windows) at run time.
Manipulating the Client Server MDI Application Window at Form StartupThe When-New-Form-Instance trigger below implements the following functionality:
• Maximizing the MDI application window
• Setting the window title of the MDI application window
The When-New-Form-Instance Trigger at Form LevelBEGIN
SET_WINDOW_PROPERTY(forms_mdi_window, window_state, maximize);SET_WINDOW_PROPERTY(forms_mdi_window, title, ’Summit Sporting
Goods.’);END;
Locating the Cursor WindowThe cursor may be located in a nonactive window. In this case, you can use the following GET_CURSOR_WINDOW function to find this window.
FUNCTION get_cursor_windowRETURN VARCHAR2ISBEGIN
RETURN (GET_VIEW_PROPERTY(GET_ITEM_PROPERTY( NAME_IN(’system.cursor_item’),item_canvas), window_name));END;
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......................................................................................................................................................Lesson 5: Controlling Windows and Canvases Programmatically
Instructor NoteDemonstration: Use window.fmb to demonstrate to the Close option from either the Microsoft or Java Windows System menu.
Copyright Oracle Corporation, 2001. All rights reserved.®
Window with Close Optionon System Menu Box
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......................................................................................................................................................Closing Windows
Closing WindowsUse the Microsoft Windows close button, or system-menu box, to provide the user with a means for closing windows. There is no default behavior in Forms when a user clicks on the close button, therefore you must define a When-Window-Closed trigger.
The following examples show a form based on departments and employees. The department block and the employee block are located in separate windows. The form level triggers When-Window-Closed and When-Window-Activated implement the following functionality:
• Exiting from the form or hiding the window that is closed by the user (Forms automatically activates another window.)
• Forcing navigation in the newly activated window
Note: The function GET_CURSOR_WINDOW, discussed in an earlier example, is used here.
The When-Window-Closed Trigger at Form LevelBEGIN
IF :SYSTEM.EVENT_WINDOW = ’WINDOW1’ THENDO_KEY(’exit_form’);
ELSIF :SYSTEM.EVENT_WINDOW = ’WINDOW2’ THENHIDE_WINDOW(’window2’);
END IF;END;
The When-Window-Activated Trigger at Form LevelBEGIN
IF :SYSTEM.EVENT_WINDOW = get_cursor_window THENRETURN;
ELSIF :SYSTEM.EVENT_WINDOW = ’WINDOW1’ THENGO_BLOCK(’s_dept’);
ELSIF :SYSTEM.EVENT_WINDOW = ’WINDOW2’ THENGO_BLOCK(’s_emp’);
END IF;END;
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......................................................................................................................................................Lesson 5: Controlling Windows and Canvases Programmatically
Copyright Oracle Corporation, 2001. All rights reserved.®
Control Window Functionalitywith Web-Deployed Forms
WIDTH=650HEIGHT=400usesdi=no
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......................................................................................................................................................Manipulating Windows in Web-Deployed Forms
Manipulating Windows in Web-Deployed FormsWhen you build Web-deployed forms, some run-time behavior is determined by Forms Applet parameters that you define in the base HTML file. The Forms Applet downloads and executes your application into an Applet area on the client browser. The parameters allow you to select either MDI or SDI options for your application and to define the size of the Applet area; this area is used as a frame for your forms windows.
The following parameters affect the run time behavior of Web form windows:
The base HTML file is downloaded when a user requests your forms application from the Web server. It contains information that would otherwise be supplied with the client server RUNFORM command.
Information on building the base HTML file is covered in the course Oracle 9iAS Forms Services: Deploy Internet Applications.
Parameter Value Description
usesdi YES Runs as a SDI Application
usesdi NO Runs as a MDI Application
width integer Width of the Applet area, in pixels
height integer Height of the Applet area, in pixels
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......................................................................................................................................................Lesson 5: Controlling Windows and Canvases Programmatically
Copyright Oracle Corporation, 2001. All rights reserved.®
Running Web-Deployed Formsin the Applet Window
usesdi=yesseparateFrame=true
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......................................................................................................................................................Sizing Windows for Web-Deployed Forms
Sizing Windows for Web-Deployed Forms
Sizing the Applet AreaThe size of the Applet area is determined by the WIDTH and HEIGHT parameters that were passed to the Forms Applet. If you run the Forms Applet within a browser HTML page, then the size of the Applet area cannot be changed at run time.
If it is running outside a browser HTML page, the Applet area will have its own window; the user can resize this window. To run the Form Applet in a separate Applet window, you can set the separateFrame parameter:
If your form module canvases must be larger than the Applet window, then you should either specify window scrollbars, or consider other Form Builder features such as Tab canvases, Tree objects, and scrollable Stacked canvases. With these you can extend the available canvas area within a form module without creating large canvases.
Parameter Value Description
separateFrame false Forms application runs in Applet area.
separateFrame true Forms application runs in a separate window outside the browser.
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......................................................................................................................................................Lesson 5: Controlling Windows and Canvases Programmatically
Instructor NoteUse largeform.fmb to demonstrate the implementation of stacked canvases for large records.
Use custwiz.fmb to demonstrate the implementation of wizards for large records. The building of wizards is covered in a later lesson.
Use summitcust.fmb to demonstrate the implementation of hierarchical tree items and tab canvases for large records.
Copyright Oracle Corporation, 2001. All rights reserved.®
Display Large Data Blocks in a Window
Applet area WIDTH = 750Customer Canvas WIDTH = 2000
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......................................................................................................................................................Display Large Data Blocks in a Window
Display Large Data Blocks in a WindowWith stacked canvases, you can increase the canvas area within a form module, without defining large form windows. To allow the user to view the entire contents of large multiple records, you should place some of the text items on a scrollable canvas. At run time, users can use the canvas scrollbar, or functionality provided by using the SCROLL_VIEW built-in, to view their data.
Web Design TipWhen you design your base HTML file you can incorporate standard HTML features, such as lines, tables, and frames. By placing the Form Applet within a specific frame, you can give your Forms application a more integrated look and feel in your Web page.By deliberately sizing your form module window larger than the Applet area and by preventing the user from moving or resizing the window, you can hide the window title bar and frame from your Web users. This will enable you to present the form application as an integral part of the HTML page.
For information on manipulating the base HTML file, attend the course Oracle 9iAS Forms Services: Deploy Internet Applications.
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......................................................................................................................................................Lesson 5: Controlling Windows and Canvases Programmatically
Copyright Oracle Corporation, 2001. All rights reserved.®
Managing Imagesfor Web-Deployed Forms
• Application images are specified outside the formmodule
– Splash screens
– Background images
• Form Module images are specified within the form
– Image Items
– Boilerplate Images
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......................................................................................................................................................Managing Images for Web-Deployed Forms
Managing Images for Web-Deployed FormsYou can display images with Form Builder in image items or as a boilerplate object on a canvas. With Web-deployed forms you can also specify Splash and Background images. The splash screen is only displayed while the Forms Applet is downloaded. You can customize the splash screen image by specifying the splashScreen parameter for the Forms Applet.
Background images are displayed in the Applet area until the application is terminated. You can display a background image by specifying the backGround parameter for the Forms Applet.
Web Design TipMinimize the use of background objects on your canvases. There is an overhead in downloading images, boilerplate text, and graphics, which can adversely affect performance in Web-deployed forms. Therefore you should try to:
• Use the Prompt item property instead of boilerplate text.
• Define only common boilerplate graphics such as rectangles and lines.
For further information on the performance of Web-deployed forms, see the course Oracle 9iAS Forms Services: Deploy Internet Applications.
Parameter Description
splashScreen Identifies the file containing image to be displayed
backGround Identifies the file containing image background
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......................................................................................................................................................Lesson 5: Controlling Windows and Canvases Programmatically
Copyright Oracle Corporation, 2001. All rights reserved.®
Summary
In this lesson, you should have learned how to:
• Manage Window-interaction with
– SYSTEM.EVENT_WINDOW
– Window triggers
– Window Built-ins
• Manipulate canvases and tab canvaseswith Built-ins
Copyright Oracle Corporation, 2001. All rights reserved.®
Summary
• Relate Windows to Data Blocks
– Multiple blocks correspond to multiplewindows.
– Window activation does not induce navigation.
– Transaction management is block-oriented.
• Manage Windows in Web-deployed forms
– MDI and SDI windows
– Sizing the Applet area
– Managing Images
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......................................................................................................................................................Summary
Summary
Window-Interaction Triggers• When-Window-Activated
• When-Window-Deactivated
• When-Window-Closed
• When-Window-Resized
Use the SYSTEM.EVENT_WINDOW system variable to keep track of the triggered window.
Built-ins for Manipulating Windows• Manipulating Windows
• Manipulating Canvases
• Manipulating Views
Windows and Blocks• Windows may contain multiple blocks and blocks may be located
on several windows.
• Forms will not automatically navigate to an item located in an activated window.
• Transaction management is block-oriented rather than window-oriented.
Web-deployed Forms• MDI and SDI windows
• Applet Areas
• Separate frames
• Display Large Data Blocks
• Splash Screens and Background Images
5-30 Oracle iDS Forms: Build Internet Applications II......................................................................................................................................................
......................................................................................................................................................Lesson 5: Controlling Windows and Canvases Programmatically
Copyright Oracle Corporation, 2001. All rights reserved.®
Practice 5 Overview
This practice covers the following topics:
• Building a multiple-window form
– Using window interaction triggers
– Using window and canvas-view built-ins
• Enhancing the tab canvas functionality by
– Customizing tab page navigation
– Disabling tab pages
Oracle iDS Forms: Build Internet Applications II 5-31......................................................................................................................................................
......................................................................................................................................................Practice Overview: Lesson 5
Practice Overview: Lesson 5This practice guides you through managing a multiple-window form and tab canvases programmatically.
Practice Contents• Build a multiple-window form and use the appropriate window
interaction triggers and built-ins to:
- Exit the form when in the primary content canvas window
- Navigate to the primary content canvas window when closing another window in the form
- Enforce navigation between form windows
• Customize tab page navigation.
• Disable the Customers comment tab page when there is no data to display.
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......................................................................................................................................................Lesson 5: Controlling Windows and Canvases Programmatically
Practice 5 1 Manipulate a multiple-window form.
a In your ORDERS form module, ensure that the form is exited when a user closes the Orders window using the window system menu box. An alert should be displayed to users asking them to confirm that they wish to leave the application.
b If a user closes the Inventory window through the system menu box, ensure that the form remains open with the cursor positioned in the Orders window.
c Whenever the user navigates between the Order and Inventory windows, place the cursor in the first navigable item within the current window.
d Save and compile your form. Deploy your form to the Web to test.
2 In your CUSTOMERS form module, define triggers to manage tab page navigation.
a Using an appropriate trigger, disable the COMMENTS tab page whenever the COMMENTS item contains no text.
b The trigger should fire whenever the user navigates to another record.
c Whenever the user moves from one tab page to another, ensure that the mouse cursor is placed in the first navigable field within the page.
d Save and compile your form. Deploy your form to the Web to test.
If you have time3 How can you ensure that the user is returned to the first navigable item
within a tab page after navigating from the last navigable item?
4 How can you enforce item navigation dynamically within a tab page?
6-2 Oracle iDS Forms: Build Internet Applications II......................................................................................................................................................
......................................................................................................................................................Lesson 6: Defining Data Sources
Instructor NoteTopic TimingLecture 40 minutes
Practice 30 minutes
Total 70 minutes
Copyright Oracle Corporation, 2001. All rights reserved.®
Objectives
After completing this lesson, you should be able todo the following:
• Describe the various data source types
• Base a data block on a FROM clause query
• Describe the advantages of using aFROM clause query
Copyright Oracle Corporation, 2001. All rights reserved.®
Objectives
After completing this lesson, you should be able todo the following:
• Base a data block on a stored procedure
• Return a REF cursor from a stored procedure
• Return a table of records from a stored procedure
• Select the appropriate data source for adata block
Oracle iDS Forms: Build Internet Applications II 6-3......................................................................................................................................................
......................................................................................................................................................Introduction
Introduction
OverviewThis lesson introduces you to the different data source types that you can use for data blocks. This lesson also provides you with some guidelines for choosing the best data source for the job.
ObjectivesAfter completing this lesson, you should be able to do the following:
• Describe the various data source types
• Base a data block on a FROM clause query
• Discuss the advantages of using a FROM clause query
• Base a data block on a stored procedure that returns a REF cursor
• Select the appropriate data source for a data block
6-4 Oracle iDS Forms: Build Internet Applications II......................................................................................................................................................
......................................................................................................................................................Lesson 6: Defining Data Sources
Copyright Oracle Corporation, 2001. All rights reserved.®
TableTable
Transactionaltrigger
Transactionaltrigger
FROM clause query
Storedprocedure
Data Source Types
Query
Company Name:Company Code:
Balance:
DML
Storedprocedure
Oracle iDS Forms: Build Internet Applications II 6-5......................................................................................................................................................
......................................................................................................................................................Data Source Types
Data Source TypesIn the previous course, Oracle 9iDS Forms: Build Internet Applications I, you learned that a data block had a base table that served as the data source for both queries and DML operations. A base table is not the only source for a data block, however, and you can specify the data source for the query separately from DML.
Data Sources for Query OperationsFor query operations, you can base your blocks on:
• Database tables or views
• Stored procedures
• Transactional triggers
• The FROM clause query (subquery)
You can also change the base table of a block dynamically at run time.
Data Sources for DML OperationsFor DML operations, you can base your blocks on:
• Database tables or views
• Stored procedures
• Transactional triggers
A data block based on a stored procedure can return data from a REF cursor or a PL/SQL table of records. If your data block has database-intensive multiple validation lookup or derived fields, this method of partitioning application logic onto the server can improve application performance.
6-6 Oracle iDS Forms: Build Internet Applications II......................................................................................................................................................
......................................................................................................................................................Lesson 6: Defining Data Sources
Instructor NoteDemonstration: Run the from_clause.sql and from_clause3.sql scripts to illustrate a FROM clause query.
Copyright Oracle Corporation, 2001. All rights reserved.®
Basing a Data Blockon a FROM Clause Query
SELECT...
FROM...
WHERE...
(SELECT...
FROM...
WHERE...)
Copyright Oracle Corporation, 2001. All rights reserved.®
Why Use a FROM Clause Query?
Perform joins, lookups, and calculations on theserver (thus avoiding multiple network trips) withouthaving to define a view every time
• Improves developer productivity
• Reduces the burden on the DBA
• Improves performance
Oracle iDS Forms: Build Internet Applications II 6-7......................................................................................................................................................
......................................................................................................................................................Basing a Data Block on a FROM Clause Query
Basing a Data Block on a FROM Clause QueryYou can use a FROM clause query as the data source for a data block. A FROM clause query is a feature of the Oracle Server that enables you to nest a SELECT statement in the FROM clause of a SELECT statement.
A FROM clause query is a valid query block data source, but it is not a valid DML block data source. The value returned from a FROM clause query is a subset of records from the original query.
ExampleSELECT deptno, sal_total
FROM
( SELECT deptno, SUM(sal) sal_total
FROM emp
HAVING SUM(sal) > 5000
GROUP BY deptno
)
ORDER BY deptno ;
Why Use a FROM Clause Query?FROM clause queries are used to perform:
• Joins
• Lookups
• Calculations
This is done without having to create a view on the server. FROM clauses queries can also be used to prototype views and to increase performance.
Using a FROM clause query as a block data source is similar to using a view based on an updatable join as a block data source. However, a FROM clause query provides you with more control, because the presence of a DBA is not required to define the view.
Note: The FROM clause query produces results that are identical to an updatable join-view from the client side, but for which there is no defined view on the server.
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......................................................................................................................................................Lesson 6: Defining Data Sources
Copyright Oracle Corporation, 2001. All rights reserved.®
CompanyName:Company Code:
Balance:Balance:
Basing a Data Block on a StoredProcedure for Query Operations
Return data by way of:
• REF cursor
• A Table of records
Procedure
Company Name:Company Code:
Querying Data block
Empno Ename Job Hire date1234 Jones Clerk 01-Jan-951235 Smith Clerk 01-Jan-951236 Adams Clerk 01-Jan-951237 Clark Clerk 01-Jan-95
Copyright Oracle Corporation, 2001. All rights reserved.®
Basing a Data Block on a StoredProcedure for DML Operations
• Return data by way of a table of records
CompanyName:Company Code:
Balance:Balance:
Company Name:Company Code:
Updating Data block
Empno Ename Job Hire date1234 Jones Clerk 01-Jan-951235 Smith Clerk 01-Jan-951236 Adams Clerk 01-Jan-951237 Clark Clerk 01-Jan-95
Procedure
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......................................................................................................................................................Basing a Data Block on a Stored Procedure
Basing a Data Block on a Stored ProcedureYou can base a data block on a stored procedure. A stored procedure returns data by using either a REF cursor or a table of records.
What Is a REF Cursor?A REF cursor defines a SELECT statement that is the source of the records. You can use this cursor to perform array fetches of SELECT statements opened by a server-side procedure.
A REF cursor is a pointer to a server-side cursor variable. It is analogous to a pointer in C in that it is an address to a location in memory. The stored procedure returns a reference to a cursor that is open and populated by a SELECT statement to be used as a block data source.
A stored procedure that uses a REF cursor can be used only as a query block data source; it cannot be used as a DML block data source. Using a REF cursor is ideal for queries that depend only on variations in SQL SELECT statements and not PL/SQL.
What Is a Table of Records?A table of records is a PL/SQL V2.3 variable that is essentially an array of rows.
You can think of a table of records as an image of a table in memory. The server-side procedure constructs this array, usually based on parameters passed to it, and passes back the resulting “set” of records to a data block. Forms treats the resulting table of records exactly as if it were fetching a series of rows from a table.
Unlike a view or a REF cursor, you are not limited to what you can express as a SQL SELECT statement. Anything you can code in PL/SQL is possible; for example, a tree-walk that includes a join.
Using a table of records is extremely efficient in terms of the savings on network traffic because it takes a single round-trip (from client to server) to execute the stored procedure and a single round-trip to return the records.
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......................................................................................................................................................Lesson 6: Defining Data Sources
Instructor NoteDemonstration: Edit the RefCurSpec.sql and RefCurBody.sql scripts to show the code of a stored procedure using a REF cursor.
Copyright Oracle Corporation, 2001. All rights reserved.®
Example of Query Usinga REF Cursor Procedure
Define a package specification with:
• The objects returned by the REF cursor
• The REF cursor
• The query procedure: Data returnedthrough the first argument (IN OUT)
Define a package body: Write the code forthe query procedure
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......................................................................................................................................................Example of a Query Using a REF Cursor Procedure
Example of a Query Using a REF Cursor ProcedureThis is an example of a stored procedure that returns a REF cursor as a block data source. A package is used to group the related data types and procedures logically.
-- Define Package Specification
PACKAGE emp_pkg IS
-- Defines the objects returned by the REF Cursor
TYPE emprec IS RECORD ( empno emp.empno%TYPE,
ename emp.ename%TYPE );
-- Defines the Ref Cursor
TYPE empcur IS REF CURSOR RETURN emprec;
-- Defines the procedure used for querying records
PROCEDURE empquery_refcur ( block_data IN OUT empcur,
p_deptno IN NUMBER);
END;
-- Defines Package Body
PACKAGE BODY emp_pkg IS
PROCEDURE empquery_refcur ( block_data IN OUT empcur,
p_deptno IN NUMBER)
IS
BEGIN
OPEN block_data FOR
SELECT empno, ename
FROM emp
WHERE deptno = NVL( p_deptno, deptno )
ORDER BY empno;
END;
END;
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......................................................................................................................................................Lesson 6: Defining Data Sources
Instructor NoteDemonstration: Edit the TorQuerySpec.sql and TorQueryBody.sql scripts to show the code of a stored procedure using a table of records.
Copyright Oracle Corporation, 2001. All rights reserved.®
Example of Query Usinga REF Cursor Procedure
Define a package specification with:
• The objects returned by the REF cursor
• The REF cursor
• The query procedure: Data returnedthrough the first argument (IN OUT)
Define a package body: Write the code forthe query procedure
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......................................................................................................................................................Example of Query Using a Table of Records Procedure
Example of Query Using a Table of Records ProcedureThis is an example of a stored procedure that returns a table of records as a block data source. A package is used to group the logically related data types and procedures.
-- Define Package Specification
PACKAGE emp_pkg IS
-- Defines each row of the table
TYPE emprec IS RECORD ( empno emp.empno%TYPE,
ename emp.ename%TYPE );
-- Defines the Table of records
TYPE emptab IS TABLE OF emprec INDEX BY BINARY_INTEGER;
-- Defines the procedure used for querying records
PROCEDURE empquery_tab ( block_data IN OUT emptab,
p_deptno IN NUMBER );
END;
-- Defines Package Body
PACKAGE BODY emp_pkg IS
PROCEDURE empquery_tab ( block_data IN OUT emptab,
p_deptno IN NUMBER )
IS
i NUMBER;
CURSOR empsel IS
SELECT empno, ename
FROM emp
WHERE deptno = NVL( p_deptno, deptno );
BEGIN
OPEN empsel;
i := 1;
LOOP
FETCH empsel INTO block_data(i).empno,
block_data(i).ename;
EXIT WHEN empsel%NOTFOUND;
i := i + 1;
END LOOP;
END;
END;
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......................................................................................................................................................Lesson 6: Defining Data Sources
Note See Appendix F, “Handling Server-Side Errors” for code details.
Instructor NoteDemonstration: Edit the TorDMLSpec.sql and TorDMLBody.sql scripts to demonstrate the code for a table of records in a stored procedure.
Copyright Oracle Corporation, 2001. All rights reserved.®
Example of DML Usinga Table of Records Procedure
Define a package specification with:
• The structure of each row of the table
• The table of records
• A procedure to insert rows
• A procedure to update rows
• A procedure to delete rows
• A procedure to lock rows
Define a package body by writing the code for
each DML procedure
Oracle iDS Forms: Build Internet Applications II 6-15......................................................................................................................................................
......................................................................................................................................................Example of DML Using a Stored Procedure
Example of DML Using a Stored ProcedureThis is an example of a stored procedure that inserts rows using a table of records as a block data source. A package is used to group the logically related data types and procedures. You should define procedures that update, delete, and lock rows also.
-- Define Package Specification
PACKAGE emp_pkg IS
-- Defines each row of the table
TYPE emprec IS RECORD ( empno emp.empno%TYPE,
ename emp.ename%TYPE,
mgr emp.mgr%TYPE,
deptno emp.deptno%TYPE );
-- Defines the Table of records
TYPE emptab IS TABLE OF emprec INDEX BY BINARY_INTEGER;
-- Defines the procedure used for inserting records
PROCEDURE empinsert ( block_data IN emptab );
END;
-- Defines Package Body
PACKAGE BODY emp_pkg IS
PROCEDURE empinsert ( block_data IN emptab )
IS
i NUMBER;
cnt NUMBER;
BEGIN
cnt := block_data.count;
FOR i IN 1..cnt LOOP
INSERT INTO emp (empno, ename, mgr, deptno)
VALUES (block_data(i).empno, block_data(i).ename,
block_data(i).mgr, block_data(i).deptno);
END LOOP;
END;
END;
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......................................................................................................................................................Lesson 6: Defining Data Sources
Copyright Oracle Corporation, 2001. All rights reserved.®
Returning a REF Cursor
Query
Fetched rows
REF cursor
REF cursor
Procedure
SQLSELECT
21
3
4
Copyright Oracle Corporation, 2001. All rights reserved.®
Returning a Table of Records
Query
Table of records
Cursor
Cursor
Procedure
AnyPL/SQL
code
21
3
4
Oracle iDS Forms: Build Internet Applications II 6-17......................................................................................................................................................
......................................................................................................................................................Deciding Whether to Use a REF Cursor or a Table of Records
Deciding Whether to Use a REF Cursor or a Tableof RecordsWhen deciding whether to use a REF cursor or a table of records, take into account the following considerations.
Queries or DML on a TableExecuting queries or DML on a table takes one round trip per array size of rows returned.
Queries with Stored Procedure Returning a REF CursorExecuting queries using a stored procedure that returns a REF cursor takes one round trip to execute the stored procedure(1, 2), plus one round trip (3, 4) per array size of rows returned.
Queries or DML with Stored Procedure Using PL/SQL Tables of RecordsExecuting queries or DML with stored procedures using PL/SQL tables of records takes one round trip to execute the stored procedure (1,2) plus one round trip (3,4) for all the rows.
Performance Implications of REF Cursors or Table of RecordsIf you are dealing with a large number of rows, the disadvantage of PL/SQL tables of records is that all the rows must be processed at once. For querying, this means you might retrieve rows that the user does not need and never displays.
• REF cursor: The number of records fetched depends on the Array Fetch property value.
• Table of records: All records are fetched.
If you want to view all records, a table of records is more efficient. However, if the table of records returns 10,000 records and you look only at 3, it is not an efficient option. For querying and DML, you use an unnecessary amount of memory because all the rows must be in memory at the same time.
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......................................................................................................................................................Lesson 6: Defining Data Sources
Instructor NoteDemonstration: If they do not already exist, create and populate the EMP and DEPT tables using the UTLSample.sql file. Run the TorDMLSpec.sql and TorDMLBody.sql scripts.
Create a new form module. Base the block on a stored procedure.
The query procedure is emp_pkg.empquery.
The insert procedure is emp_pkg.empinsert.
The update procedure is emp_pkg.empupdate.
The delete procedure is emp_pkg.empdelete.
The lock procedure is emp_pkg.emplock.
Copyright Oracle Corporation, 2001. All rights reserved.®
Data Block Wizard
Use the Data Block Wizard to specify the following:
• Data source type
• Query procedure
• Insert procedure
• Update procedure
• Delete procedure
• Lock procedure
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......................................................................................................................................................Data Block Wizard
Data Block WizardThe Data Block Wizard simplifies and automates the process of creating blocks. You saw how to use it in the previous course, Oracle 9iDS Forms: Build Internet Applications I.
Use the Data Block Wizard even if you want to create a data block based on stored procedure. You just have to specify the following:
Property Description
Data source type Specifies if the data block is based on a table or a stored procedure
Query procedure Name of the procedure used to query rows
Insert procedure Name of the procedure used to insert rows
Update procedure Name of the procedure used to update rows
Delete procedure Name of the procedure used to delete rows
Lock procedure Name of the procedure used to lock rows
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......................................................................................................................................................Lesson 6: Defining Data Sources
Instructor NoteDemonstration: Use the form created previously to illustrate these properties.
Copyright Oracle Corporation, 2001. All rights reserved.®
Data Block Properties for Queries
Copyright Oracle Corporation, 2001. All rights reserved.®
Data Block Properties for DML
Oracle iDS Forms: Build Internet Applications II 6-21......................................................................................................................................................
......................................................................................................................................................Data Block Properties
Data Block Properties
Data Block Properties for Queries
Data Block Properties for DML
Property Description
Query Data Source Type Specifies the query data source type for the data block
Query Data Source Name Specifies the name of the block query data source. (Used when the query data source type is Table, Sub-query, or Procedure.)
Query Data Source Columns Specifies the names and data types of columns associ-ated with the query data source. (Used when the query data source type is Table, Subquery, or Procedure.)
Query Data Source Arguments Specifies the names, data types, and values of the argu-ments that are to be passed to the procedure for query-ing data (Used only if the query data source type is Procedure.)
Property Description
DML Data Target Type Specifies the DML data source type for the data block
DML Data Target Name Specifies the name of the DML data source for the data block (Used only if the DML data target type is Table.)
(Insert, Update, Delete, Lock) Procedure Name
Specifies the name of the procedure to be used (Used only if the DML data target type is Procedure.)
(Insert, Update, Delete, Lock) Procedure Result Set Columns
Specifies the names and data types of the result set columns associated with the procedure (Used only if the DML data target type is Procedure.)
(Insert, Update, Delete, Lock) Procedure Arguments
Specifies the names, data types, and values of the arguments that are to be passed to the procedure (Used only if DML data target type is Procedure.)
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......................................................................................................................................................Lesson 6: Defining Data Sources
Instructor NoteDemonstration: Use the Stored Procedures demonstration to illustrate how to use the same block to display data from different tables. Before the demonstration, run the OrderSpec.sql and OrderBody.sql scripts.
Copyright Oracle Corporation, 2001. All rights reserved.®
Data Source Guidelines
Base a data block on a FROM clause query to:
• Create a “dynamic” view
• Perform validation and DML on theserver side
Copyright Oracle Corporation, 2001. All rights reserved.®
Data Source Guidelines
Base a data block on a stored procedure to:
• Increase control and security
• Specify a SELECT statement at run time
• Query or update multiple tables
• Perform complex computations
• Perform validation and DML on theserver side
Oracle iDS Forms: Build Internet Applications II 6-23......................................................................................................................................................
......................................................................................................................................................Data Source Guidelines
Data Source Guidelines
Using a FROM Clause QueryYou base a data block on a FROM clause query to:
• Create a dynamic view
• Perform validation and DML on the server side
Using Stored ProceduresYou base a data block on a stored procedure when you want to:
• Increase control and security
Using a stored procedure, you do not have to grant select access on the table to the users, just EXECUTE privileges on the procedure.
• Specify a SELECT statement at run time
Using a REF cursor, if the logged-on user is a manager, open the cursor as SELECT last_name, salary FROM s_emp; otherwise open the cursor as SELECT last_name, null FROM s_emp.
• Base a block on multiple tables
Using a REF cursor and depending on some parameter to the procedure, you could open the cursor either as SELECT * FROM open_orders (current data) or as SELECT * FROM closed_orders (old data).
• Perform complex computations and decisions
Using a table of records, return the salary of all employees that you manage, but NULL for the salary of other employees.
• Perform validation and DML on the server side
If your data block has multiple validation lookup or derived fields that are database-intensive, this method of partitioning the application logic onto the server can vastly improve the performance of applications.
• Encapsulate logic within a subprogram
• Reduce traffic through array processing, using a REF cursor
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......................................................................................................................................................Lesson 6: Defining Data Sources
Copyright Oracle Corporation, 2001. All rights reserved.®
Data Source Guidelines
Query
YES
YES
YES
YES
YES
YES
Data Source
Table
View
FROM Clause
Proc-Ref Cur
Proc-Table Rec
Transac. Trigger
DML
YES
YES
NO
NO
YES
YES
Oracle iDS Forms: Build Internet Applications II 6-25......................................................................................................................................................
......................................................................................................................................................Data Source Guidelines
Data Source Type RestrictionsWhen deciding on a data block source, consider your requirements:
• Will the block be used only to query records?
• Will the block be used to perform inserts, updates, and deletes?
• Will the block be used to perform both query and DML?
To decide, you should also consider the functional restrictions for each data source type:
Data Source Allows Query Allows DML
Table Yes Yes
View Yes Yes
FROM Clause Yes No
Procedure Using a REF Cursor Yes No
Procedure Using a Table of Records Yes Yes
Transactional Trigger Yes Yes
6-26 Oracle iDS Forms: Build Internet Applications II......................................................................................................................................................
......................................................................................................................................................Lesson 6: Defining Data Sources
Copyright Oracle Corporation, 2001. All rights reserved.®
Summary
In this lesson, you should have learned to:
• Base data blocks on new data sources:
– FROM clause query (query only)
– Stored procedure (query and DML)
• Exploit features of stored procedures:
– REF cursors
– Limited to a single SELECT statement
– Table of records
– Can be a complex procedure
Copyright Oracle Corporation, 2001. All rights reserved.®
Summary
• Use the Data Block Wizard to specify:
– Data source type
– Procedures for queries, updates,deletes, and locking
Oracle iDS Forms: Build Internet Applications II 6-27......................................................................................................................................................
......................................................................................................................................................Summary
Summary
New Data Sources• Stored procedure (query and DML)
• FROM clause query (query only)
Stored Procedures Return• REF cursors—limited to a single SELECT statement
• Table of records—can be a complex procedure
Using the Data Block Wizard• Specify data source type
• Specify procedures for queries, updates, deletes, and locking
6-28 Oracle iDS Forms: Build Internet Applications II......................................................................................................................................................
......................................................................................................................................................Lesson 6: Defining Data Sources
Copyright Oracle Corporation, 2001. All rights reserved.®
Practice 6 Overview
This practice covers the following topics:
• Creating a package containing a storedprocedure to return a REF cursor
• Creating a data block based on a REF cursorstored procedure
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......................................................................................................................................................Practice Overview: Lesson 6
Practice Overview: Lesson 6This practice guides you through creating a data block based on stored procedures.
Practice Contents• Create a package containing a stored procedure to return a REF Cursor
• Create a data block based on a stored procedure
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......................................................................................................................................................Lesson 6: Defining Data Sources
Practice 6 1 Create a server-side package containing a procedure to return a REF
cursor.
a Create the Orders_pkg package specification; you can import the code from the pr6_1.txt file.
b Create the Orders_pkg package body; you can import the code from the pr6_2.txt file.
c Examine the Orders_pkg package body to identify required parameter values.
2 Open the ORDERREFCURSOR.fmb file and save as ORDREFXX where XX is your student course number. This form contains a control block, called CHOOSE, and a group of option buttons, which allows the user to specify a parameter value to be passed to the REF cursor.
a Create a data block called SELECTION and base it on the REF cursor procedure that you have just created.
b Pass the name of the radio group as the value for the P_VIEW argument: ‘:choose.view_type’ .
c In the layout editor, customize the canvas layout to ensure that SELECTION items are displayed to the left of the option buttons group.
d Save and compile your form. Deploy your form to the Web to test.
7-2 Oracle iDS Forms: Build Internet Applications II......................................................................................................................................................
......................................................................................................................................................Lesson 7: Working with Oracle8i Objects in Form Builder
Copyright Oracle Corporation, 2001. All rights reserved.®
Objectives
After completing this lesson, you shouldbe able to:• Recognize which object types are supported
• Describe how object types arerepresented within Form Builder
• Create a block based on an object table
• Create a block based on a relation tablewith an object or an REF column
• Populate a REF column with an LOV
Oracle iDS Forms: Build Internet Applications II 7-3......................................................................................................................................................
......................................................................................................................................................Introduction
Introduction
OverviewThis lesson reviews certain object features of Oracle8i and explains how these objects are displayed in the Object Navigator.
ObjectivesAfter completing this lesson, you should be able to do the following:
• Recognize which Oracle8i object types are supported
• Describe how Oracle8i objects are represented within Form Builder
• Create a block based on an object table
• Create a block based on a relational table with an object column or REF column
• Populate a REF column with an LOV
7-4 Oracle iDS Forms: Build Internet Applications II......................................................................................................................................................
......................................................................................................................................................Lesson 7: Working with Oracle8i Objects in Form Builder
Copyright Oracle Corporation, 2001. All rights reserved.®
Object Types
Ship
Cancel
Hold
Checkstatus
Attributes
Methods
ORDERpo_no
custinfoline_items
amount
Oracle iDS Forms: Build Internet Applications II 7-5......................................................................................................................................................
......................................................................................................................................................What Are Object Types?
What Are Object Types?An object type is a user-defined composite data type. It is in some ways similar to a record type, and in some ways similar to a package.
An object type is similar to a record type in that it is composed of one or more subparts that are of predefined data types. Record types call these subparts “fields,” but object types call these subparts “attributes.” Just as the fields of a record type can be of other record types, the attributes of an object type can be of other object types. Such an object type is called “nested.”
Object types are like record types in another sense: both of them must be declared as types before the actual object or record can be declared.
An object type is also similar to a package. After an object is declared, its attributes are similar to package variables. Like packages, object types can contain procedures and functions. In object types, these subprograms are known as “methods.”
As with packages, object types can be declared in two parts: a specification and a body. Like package variables, attributes declared in the object type specification are public and those declared in the body are private, and as with package subprograms, all methods are defined in the package body, but only those whose specification appears in the object type specification are public methods.
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Copyright Oracle Corporation, 2001. All rights reserved.®
Review of Objects
• Object tables
• Object columns
• Object views
• INSTEAD-OF triggers
DECLARE
BEGIN
EXCEPTION
END;
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......................................................................................................................................................Review of Objects
Review of ObjectsWith an object type, you can create object tables, object columns, object views, and INSTEAD-OF triggers.
Object TablesAfter you have declared an object type, you can create objects based on the type. One way to do this is to create a table whose rows are objects of that object type. Rows in an object table are assigned object IDs (OIDs) and can be referenced using a REF type.
Object ColumnAnother construct that can be based on an object type is an object column in a relational table. In the object table, the rows of a table are objects. In a relational table with an object column, the column is an object. The table usually has standard columns, as well as one or more object columns. Object columns are not assigned OIDs, and thus cannot be referenced using object REF values.
Object ViewAn object view transforms the way a table appears to a user, without changing the actual structure of the table. Object views make relational tables look like object tables. Objects accessed through object views are assigned OIDs, and can be referenced using object REFs.
INSTEAD OF Triggers INSTEAD OF triggers provide a transparent way of modifying views that cannot be modified directly through SQL DML statements (INSERT, UPDATE, and DELETE). These triggers are called INSTEAD-OF triggers because, unlike with other types of triggers, the Oracle server fires the trigger instead of executing the triggering statement. The trigger performs update, insert, or delete operations directly on the underlying tables.
Technical NoteThe Database Trigger Editor includes the INSTEAD-OF triggering event.
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Copyright Oracle Corporation, 2001. All rights reserved.®
References to Objects
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......................................................................................................................................................Object REFs
Object REFsWhen a row in an object table or object view is created, it is automatically assigned a unique identifier called an object ID (OID). This OID value can be stored in attributes of other objects, or columns of other tables. The stored copy of the OID then becomes a pointer, or REF, to the original object. (Object columns are not assigned OIDs and cannot be pointed to by a REF.)
In relational databases, primary key values are used to identify records uniquely. In object-relational databases, OIDs provide an alternate method.
With relational tables, you can associate two records by storing the primary key of one record in one of the columns (the foreign key column) of another. In a similar way, you can associate two objects by storing the OID of one object in an attribute of another, you can associate a row in a relational table to an object by storing the OID of an object in a column of a relational table. The attribute or column that holds the OID is of data type REF.
Remember, only the OID value for the object is stored in the table, not the object itself.
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......................................................................................................................................................Lesson 7: Working with Oracle8i Objects in Form Builder
Copyright Oracle Corporation, 2001. All rights reserved.®
Oracle8i in Oracle Forms
Supported Oracle8i features
• Large Objects: BLOB, CLOB, NCLOB, BFILE
• User-defined objects
– Object table
– Column object
– REF column
Unsupported Oracle8 i features
• Collection types
• Stored procedures that return object values
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......................................................................................................................................................Supported Oracle8i Features
Supported Oracle8i FeaturesA number of features provided in the Oracle8i Server are available in Oracle Forms Developer. This allows greater scalability and performance in your application.
Oracle adds support for the following Oracle8i data types:
• Large objects (LOBs): BLOB, CLOB, NCLOB, BFILE
• User-defined Oracle8i objects
• An object table, where the entire table is based on a single object type (Oracle Forms Developer treats each column in an object table as an individual data item.)
• A column object in an object or relational table, where the column is based on an object type definition
• A REF column in an object or a relational table, where that column’s values are pointers to rows in a separate object table
Unsupported Oracle8i FeaturesNot all Oracle8i features are currently supported by Oracle Forms Developer. The major unsupported features are:
• Collection types, including nested tables and varying arrays
• Stored procedures that return object values
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......................................................................................................................................................Lesson 7: Working with Oracle8i Objects in Form Builder
Copyright Oracle Corporation, 2001. All rights reserved.®
How Oracle Forms Treats Objects
Object_B
Attr_B1
Attr_B2
Attr_A3
Nested Objects
Attr_A1
Attr_A2
Object_A
Attr_A1
Object_A
Attr_A3
Attr_A2_B1
Attr_A2_B2
Items in a Form
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......................................................................................................................................................How Oracle Forms Developer Treats Objects
How Oracle Forms Developer Treats ObjectsAs you have learned, Oracle8i tables can contain objects. In its support for the Oracle8i Server, Oracle Forms Developer allows you to access these objects in an application.
A table itself can be based on an object (a table object), one or more of the table columns can be based on an object (a column object), or one or more of the tables’ columns can contain a reference to an object stored in another table (REF column). Each of these objects can itself contain objects.
In these cases, the columns and attributes form a hierarchy among the Oracle8i data types. However, Oracle Forms Developer has no hierarchy of items. Each item lies directly below the block. Therefore, Oracle Forms Developer must collapse the hierarchy before the columns and attributes are mapped to items within a block. Both the hierarchy of the columns and attributes and the “flattened” nature of the resulting items are represented in Oracle Forms Developer’s displays and dialog boxes.
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......................................................................................................................................................Lesson 7: Working with Oracle8i Objects in Form Builder
Copyright Oracle Corporation, 2001. All rights reserved.®
Object Display
Object Type
Object Table
Object Column
Object REF
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......................................................................................................................................................Object Type Displays
Object Type DisplaysThe Object Navigator lists declared types under the Database Objects node, along with tables, views, and other Oracle objects. The objects in the screenshot are based on the following syntax: -- type declaration
CREATE TYPE dept_type AS OBJECT(id NUMBER,
name VARCHAR2(25),
region_id NUMBER(7) )
/
-- object table
CREATE TABLE oo_dept_table OF dept_type;
-- object column
CREATE TABLE rel_emp_table_ObjCol (id NUMBER(7),
last_name VARCHAR2(25),
first_name VARCHAR2(25),
userid VARCHAR2(8),
start_date DATE, manager_id NUMBER(7),
title VARCHAR2(25),
dept_id dept_type,
salary NUMBER(11,2),
commission_pct NUMBER(4,2) );
-- ref column
CREATE TABLE rel_emp_table_RefCol (id NUMBER(7), last_name VARCHAR2(25),
first_name VARCHAR2(25), userid VARCHAR2(8),
start_date DATE, manager_id NUMBER(7), title VARCHAR2(25), dept_id REF dept_type,
salary NUMBER(11,2),
commission_pct NUMBER(4,2) );
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......................................................................................................................................................Lesson 7: Working with Oracle8i Objects in Form Builder
Copyright Oracle Corporation, 2001. All rights reserved.®
Creating Data Blocks Basedon Oracle8i Objects
• Blocks based on object tables
• Blocks based on object columns
• Blocks with REF Lookups
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......................................................................................................................................................Creating Data Blocks Based on Oracle8i Objects
Creating Data Blocks Based on Oracle8i ObjectsOracle Forms Developer enables you to create data blocks based on Oracle8i objects. The Data Block Wizard has been enhanced to support object tables. The fields of an object are displayed in a hierarchy underneath the object column in the wizard’s Table page. Like objects in the Object Navigator, you can expand or collapse the object columns in the display.
You can base a data block on:
• An object table
• A column object
• A REF column
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......................................................................................................................................................Lesson 7: Working with Oracle8i Objects in Form Builder
Copyright Oracle Corporation, 2001. All rights reserved.®
Blocks Based on Object Tables
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......................................................................................................................................................Selecting Object Table Columns
Selecting Object Table ColumnsYou can create a data block based on a user-defined object table. In the Data Block Wizard, you select object tables the same way you select relational tables. In the wizard’s Table page, when you select an object table as the data source, it is expanded and each of its components is displayed in the Available Columns window. An outline format with indenting is used to show each component of the object.
You select the type attributes the same way you select relational table columns. Oracle Forms Developer treats each component in an object table as a separate column, and allows you to select these columns individually.
The syntax below creates an object table based on an object type:CREATE TYPE dept_type AS OBJECT
(id NUMBER,
name VARCHAR2(25),
region_id NUMBER(7) )
/
CREATE TABLE oo_dept_table OF dept_type
/
In the diagram, the wizard shows all the columns of the object table OO_DEPT_TABLE (ID, NAME, REGION_ID). Select any or all as data block items.
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Copyright Oracle Corporation, 2001. All rights reserved.®
Blocks Based on Object Columns
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......................................................................................................................................................Selecting Object Column Attributes
Selecting Object Column AttributesIf you base a block on an object or relational table with an object column, the attributes of the object column appear indented beneath the name of the object column in the Data Block Wizard. Oracle Forms Developer treats each attribute as a separate column. You can select any combination of columns or object column attributes. Once selected, they all “collapse” to the same level as an item within the new block.
Data items selected from an object are given the default name ColumnObjectName_ItemName. Selecting the object column name itself has the effect of selecting all of the attributes of the object column.
The syntax below creates a table with an object column:CREATE TYPE dept_type AS OBJECT
(id NUMBER,
name VARCHAR2(25),
region_id NUMBER(7) )
/
CREATE TABLE rel_emp_table_ObjCol (
id NUMBER(7),
last_name VARCHAR2(25),
first_name VARCHAR2(25),
userid VARCHAR2(8),
start_date DATE,
manager_id NUMBER(7),
title VARCHAR2(25),
dept_id dept_type,
salary NUMBER(11,2),
commission_pct NUMBER(4,2) );
In the diagram, the wizard displays ID, NAME, and REGION_ID as columns you can select as data block items.
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Copyright Oracle Corporation, 2001. All rights reserved.®
Blocks with REF Lookups
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......................................................................................................................................................Blocks with REF Lookups
Blocks with REF LookupsIf you base a block on an object or relational table with a REF column, the attributes of the object being referenced appear below the REF column in the Available Columns window.
Once selected, the attributes of the REF column are made into items, just like standard columns. However, the items based on REF column attributes are created with a QUERY ONLY property value of “YES,” and INSERT ALLOWED and UPDATE ALLOWED properties of “NO.”
The syntax below creates a table with a REF data type:CREATE TYPE dept_type AS OBJECT
(id NUMBER,
name VARCHAR2(25),
region_id NUMBER(7) )
/
CREATE TABLE rel_emp_table_RefCol (
id NUMBER(7),
last_name VARCHAR2(25),
first_name VARCHAR2(25),
userid VARCHAR2(8),
start_date DATE,
manager_id NUMBER(7),
title VARCHAR2(25),
dept_id REF dept_type,
salary NUMBER(11,2),
commission_pct NUMBER(4,2) );
As seen in the diagram, the REF column name (DEPT_ID) appears twice in the column selection list. It appears once as a heading for the referenced object’s attributes and then again as a pointer. The column is selectable.
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Copyright Oracle Corporation, 2001. All rights reserved.®
Using the REF Lookup Value
Select REF attribute columns: This causes thecolumns to appear as data items at run-time.Select the REF item itself:
• This causes the item to be placed on a Null canvas.
• The item does not appear at run time.
• The item is available for coding purposes.
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......................................................................................................................................................The REF Column Value
The REF Column ValueThe double listing of the REF column name affords you different choices. As with a regular column object, you can select any or all of a REF’s attribute columns. Selecting the first instance of the REF name in the diagram on the previous page selects all its parts.
When you select one or more of the REF’s attribute columns, they appear as normal data items in the data block at run time.
You can also select the REF itself, which is the second entry in the diagram on the previous page. If the REF column itself is included in the block, it is created as a nondisplay item and placed by default on the Null canvas. Although the REF item does not appear on the canvas at run time, it is still available for coding purposes.
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Copyright Oracle Corporation, 2001. All rights reserved.®
LOVs for REFs
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......................................................................................................................................................LOVs for REFs
LOVs for REFsUsers may use an LOV to select appropriate referenced values. The Data Block Wizard presents the LOV for REF window, which enables you to define an LOV.
How to Create the LOV1 Select the REF desired.
2 For the REF selected, the wizard lists all the associated tables. Select the table of your choice.
The wizard builds the LOV from the values in this table.
Note: The same LOV gets attached to all the lookup items associated with a particular REF.
REFs are defined on object types, not on specific tables. Therefore, a REF can point to multiple tables.
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......................................................................................................................................................Lesson 7: Working with Oracle8i Objects in Form Builder
Copyright Oracle Corporation, 2001. All rights reserved.®
Summary
In this lesson, you should have learned how to:
• Identify supported Oracle8i object types
• Define data blocks based on object tables
• Define data blocks based on tableswith object columns or REF columns
• Populate REF columns with an LOV
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......................................................................................................................................................Summary
Summary• Oracle Forms Developer supports most, but not all, of the Oracle8i
object types.
• In Forms Builder, object types are displayed like columns, where indentation shows the nesting of objects.
• Blocks can be based on object tables.
• Blocks based on object or relational tables can include object columns or REF columns.
• REF columns can be populated with an LOV.
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......................................................................................................................................................Lesson 7: Working with Oracle8i Objects in Form Builder
Copyright Oracle Corporation, 2001. All rights reserved.®
Practice 7 Overview
This practice covers the following topics:
• Creating a block based on a relationaltable with an object column
• Creating a block based on a relationaltable with a REF column
• Populating a REF column with an LOV
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......................................................................................................................................................Practice Overview: Lesson 7
Practice Overview: Lesson 7This practice guides you through creating data blocks based on Oracle8i object tables.
Practice Contents• Create a block based on a relational table with an object column
• Create a block based on a relational table with a REF column
• Populate a REF column with an LOV
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......................................................................................................................................................Lesson 7: Working with Oracle8i Objects in Form Builder
Practice 7 1 Create a data block based on a relational table with an object column.
a Create a form called OBJ_COLXX where XX is your student coursenumber.
b Using the Data Block Wizard, create a block based on the REL_EMP_TABLE_OBJCOL relational table.
c Select the columns ID, FIRST_NAME, and LAST_NAME.
d Expand the object column DEPT_ID and select the attributes ID and NAME. Note the names that are given to the new items.
e In the Layout Wizard, select all available items for display. Change the prompt for item DEPT_ID to Department ID and DEPT_ID_NAME to Department Name. Use a form layout.
f Save, compile, and test your form.
If you have time2 Create a block based on a relational table with an REF column, and
specify an LOV to populate the REF column.
a Create a form called REF_COLXX where XX is your student coursenumber.
b Create a block based on the REL_EMP_TABLE_REFCOL relational table.
c Select the columns ID, FIRST_NAME, and LAST_NAME.
d Select the DEPT_ID attributes ID and NAME.
e Create an LOV for the REF item DEPT_ID. Select the check box, and select OO_DEPT_TABLE as the source for the LOV.
f In the Layout Wizard, select all available items for display.
g In the Object Navigator, identify the canvas with which item DEPT_ID is associated.
h In the Object Navigator, check that an LOV and associated record group have been created.
i Save, compile, and test the form.
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......................................................................................................................................................Lesson 8: Controlling Data Block Relationships
Instructor NoteTopic TimingLecture 25 minutes
Practice 25 minutes
Total 50 minutes
Copyright Oracle Corporation, 2001. All rights reserved.®
Objectives
After completing this lesson, you should be able todo the following:
• Define block coordination
• Coordinate data blocks by using REF relations
• Describe the characteristics andprinciples of relation-handling code
• Implement a coordination-type toggle
• Force one commit per master record
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......................................................................................................................................................Introduction
Introduction
OverviewYou have seen how form modules consist of data blocks based on related tables. This lesson shows how you can modify the relationship between two data blocks to affect the way in which deletes are handled and to what extent the data blocks are coordinated at query time. Also, it explains how to create relationships based on object REFs.
ObjectivesAfter completing this lesson, you should be able to do the following:
• Define block coordination
• Coordinate data blocks by using REF relations
• Describe the characteristics and principles of relation-handling code
• Implement a coordination-type toggle
• Force one commit per master record
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......................................................................................................................................................Lesson 8: Controlling Data Block Relationships
Instructor NoteDemonstration: Use Orders3.fmb to demonstrate how to create explicitly a relation between the S_ITEM and S_INVENTORY blocks.
Copyright Oracle Corporation, 2001. All rights reserved.®
Relations
• Logical objects that handle the relationshipbetween two blocks
• Created implicitly with a master-detail form module
• Created explicitly with the New Relation dialog box
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......................................................................................................................................................Creating a Relation
Creating a Relation
What Is a Relation?A relation is a Form Builder object that handles the relationship between two associated blocks.
You can create a relation either:
• Implicitly with a master-detail form module
• Explicitly in the Object Navigator
Implicit RelationsWhen you create a master-detail form module, a relation is automatically created. This relation is named in the format masterblock_detailblock, for example, S_ORD_S_ITEM.
Explicit RelationsIf a relation is not established when default blocks are created, you can create your own, either by setting the properties in the master block New Relation dialog box, or by calling the reentrant wizard for the detail data block. Like implicitly created relations, PL/SQL program units and triggers are created automatically when you explicitly create a relation.
Instructor NoteThe creation of explicit relations was covered in the Oracle 9iDS Forms: Build Internet Applications I course. Use these pages to review the fact that relations can be created implicitly or explicitly.
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......................................................................................................................................................Lesson 8: Controlling Data Block Relationships
Instructor NoteExplain to students the importance of the Copy Value from Item property for implementing block coordination.
Demonstration: Use Orders3.fmb to demonstrate the objects used to implement a block coordination.
Copyright Oracle Corporation, 2001. All rights reserved.®
Block Coordination
• Coordination-causing event
• Block-coordination phases:
– Clear phase executed before changeof master record
– Populate phase executed afterchange of master record
• Implementation of block coordination:
– The Copy Value from Item property
– Relation-handling triggers
– Relation-handling procedures
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......................................................................................................................................................Block Coordination
Block CoordinationTo maintain a master-detail relationship, Forms coordinates the master and detail blocks to ensure that only the detail records that belong to the current master record are displayed.
Coordination-Causing EventsAny event that changes the master record is called a coordination-causing event or a coordination operation. Forms automatically coordinates the master and detail blocks again when you move to another master record.
Block Coordination Phases
Implementation of Block CoordinationForms implements block coordination through the following elements:
• The Copy Value from Item property on the foreign-key item in the detail block, which specifies the corresponding primary-key item in the master block
• Relation-handling triggers, which fire during the Clear and Populate phases of block coordination
• Relation-handling procedures, which are called from relation-handling triggers
Note: The elements above are controlled through the relation object.
Web Design TipYou can reduce potential network traffic within Web-deployed forms by specifying deferred coordination. By using relation-handling built-ins, you can give users the run-time option of selecting either immediate or deferred coordination.
Phase DescriptionClear Forms clears all detail blocks before it navigates to the new master record.
Unsaved changes in detail blocks are deleted. If the Clear phase fails, Forms stops coordination processing and does not navigate to the new master record.
Populate Forms queries all detail blocks after it has navigated to the new master record, unless the coordination type is Deferred.
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......................................................................................................................................................Lesson 8: Controlling Data Block Relationships
Copyright Oracle Corporation, 2001. All rights reserved.®
Blocks with REF Relations
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......................................................................................................................................................Coordinate Blocks Using REFs
Coordinate Blocks Using REFsMany object-oriented languages implement master-detail relations by storing in the detail data an internal identifier to the master data. This internal identifier is known as a reference (REF). To support object-oriented programming, the Data Block Wizard enables you to base the relation on a REF rather than on a foreign key.
To create a master-detail relation based on a REF, the detail block must contain the REF column. Create a master-detail form using REFs by doing the following in the Data Block Wizard:
1 Create the master block and choose the columns you wish to include as items in the block. Complete the Layout Wizard steps to finish creating and laying out the master block.
2 Create the detail block. When you choose columns, you must choose the REF column, because this value will be used to establish the relationship. You should not choose the lookup columns, because doing so causes the detail block to duplicate items that are already displayed in the master block.
3 On the Master-Detail page of the wizard, click the Create Relationship button. A dialog box appears listing all possible master blocks for the relationship. Select the appropriate master block and click OK and then Finish.
4 Complete the Layout Wizard steps to finish creating and laying out the detail block.
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Technical NoteRelation-handling triggers fire only if you have defined a corresponding relation.
Copyright Oracle Corporation, 2001. All rights reserved.®
Characteristics ofRelation-Handling Triggers
• On-Clear-Details: Implements the Clear phase
• On-Populate-Details: Implements thePopulate phase
• On-Check-Delete-Master: Implements therestricted-delete rule
• Effect of trigger failure
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......................................................................................................................................................Characteristics of Relation-Handling Triggers
Characteristics of Relation-Handling TriggersForms automatically creates and maintains relation-handling triggers to implement block coordination and restricted-delete foreign-key rules.
Note: If you specify a cascade-delete foreign-key rule for a relation, Form Builder uses a Pre-Delete trigger to implement this rule. However, this is a commit trigger, not a relation-handling trigger, and can also be used outside the context of relations.
Trigger DescriptionOn-Clear-Details Fires when a coordination-causing event occurs in a
master block, before Forms navigates to the new master record. This trigger implements the Clear phase and is defined at the form level. If it fails, the coordination-causing event is aborted.
On-Populate-Details Fires when a coordination-causing event occurs in a master block, after Forms has navigated to the new master record. However, this trigger fires only if an On-Clear-Details trigger is also defined. This trigger implements the Populate phase and is defined for each master block. If it fails, it can cause the wrong detail records to be displayed for the current master record.
On-Check-Delete-Master Fires when you attempt to delete the current master record, before Forms deletes the record. If it fails, the record deletion is aborted.
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Copyright Oracle Corporation, 2001. All rights reserved.®
Principles of Relation-Handling Code
Three relation-handling procedures:
• CLEAR_ALL_MASTER_DETAILS
• QUERY_MASTER_DETAILS
• CHECK_PACKAGE_FAILURE
Adding your own code to relation-handling triggers:
• Forms adds comments around code.
• You add your own code before or afterthese comments.
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......................................................................................................................................................Principles of Relation-Handling Code
Principles of Relation-Handling CodeForms automatically creates and maintains the PL/SQL code that is executed in the relation-handling triggers. You can add your own code to these triggers.
Three Relation-Handling Procedures
Note: The CLEAR_ALL_MASTER_DETAILS procedure gives you an example of how to walk recursively through a hierarchical tree of blocks.
Adding Your Own Code to Relation-Handling TriggersForms adds comments around the PL/SQL code that it generates for relation handling, for example:
---- Begin default relation program section--BEGIN CLEAR_ALL_MASTER_DETAILS;END;---- End default relation program section--
You can add PL/SQL code to relation-handling triggers before the “Begin default relation program section” comment or after the “End default relation program section” comment.
Note: Forms will not delete a relation-handling trigger to which you have properly added PL/SQL code.
Procedure Called FromCLEAR_ALL_MASTER_DETAILS On-Clear-Details trigger defined on the form
levelQUERY_MASTER_DETAILS On-Populate-Details trigger defined for each
master blockCHECK_PACKAGE_FAILURE On-Populate-Details trigger and the previous
procedures
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Technical NoteYou can use these system variables in the On-Clear-Details trigger only. Assign their values to global variables to broaden the scope.
Copyright Oracle Corporation, 2001. All rights reserved.®
Obtaining Relation-Handling Information
System variables for relation handling:
• SYSTEM.MASTER_BLOCK
• SYSTEM.COORDINATION_OPERATION
Built-ins for relation handling:
• GET_FORM_PROPERTY
• GET/SET_BLOCK_PROPERTY
• GET/SET _RELATION_PROPERTY
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......................................................................................................................................................Obtaining Relation-Handling Information
Obtaining Relation-Handling InformationYou can use system variables and built-ins to obtain more information about block coordination and relation properties. This is useful if you want to modify the default relation-handling triggers.
System Variables for Relation Handling
Built-ins for Relation Handling
(*): You can also set those properties using the Set-Relation-Property built-in.
Name DescriptionSYSTEM.MASTER_BLOCK Contains the name of the master block that
drives the current block coordinationSYSTEM.COORDINATION_OPERATION Contains the name of a block
coordination-causing event that occurred on the driving master block (Value examples of this system variable include NEXT_RECORD, SCROLL_DOWN, MOUSE, DELETE_RECORD, and EXECUTE_QUERY.)
Name Properties Concerning RelationsGET_FORM_PROPERTY FIRST_BLOCK,
LAST_BLOCK GET_BLOCK_PROPERTY COORDINATION_STATUS(*),
NEXTBLOCK, PREVIOUSBLOCK, FIRST_DETAIL_RELATION, FIRST_MASTER_RELATION
GET_RELATION_PROPERTY AUTOQUERY(*), DEFERRED_COORDINATION(*), MASTER_DELETES(*), PREVENT_MASTERLESS_OPERATION(*), DETAIL_NAME, MASTER_NAME, NEXT_DETAIL_RELATION, NEXT_MASTER_RELATION
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......................................................................................................................................................Lesson 8: Controlling Data Block Relationships
Instructor NoteDemonstration: Use Orders3.fmb to demonstrate the Coordination-Type Toggle.
Select Query––>Deferred.
Copyright Oracle Corporation, 2001. All rights reserved.®
Implementing aCoordination-Type Toggle
Define a procedure that toggles betweenimmediate and deferred coordination
• Use GET_BLOCK_PROPERTY to obtainrelation name.
• Use GET_RELATION_PROPERTY toobtain current coordination type.
• Use SET_RELATION_PROPERTY toswitch to other coordination type.
Copyright Oracle Corporation, 2001. All rights reserved.®
Implementing aCoordination-Type Toggle
Call this procedure from:
• When-Checkbox-Changed trigger
• Menu item of type Check
Oracle iDS Forms: Build Internet Applications II 8-17......................................................................................................................................................
......................................................................................................................................................Implementing a Coordination-Type Toggle
Implementing a Coordination-Type ToggleYou can use relation-handling built-ins to offer users the choice betweenimmediate and deferred coordination.
You can use this example procedure in a simple master-detail form and can serve as a starting point for more complex situations; for example, you can call this procedure from a When-Checkbox-Changed trigger on a check box that represents the coordination type, or from a menu item of type Check.
PROCEDURE toggle_query_sync(p_master_block in VARCHAR2)IS
v_rel_name VARCHAR2(30);v_rel_id RELATION;
BEGINv_rel_name := GET_BLOCK_PROPERTY(p_master_block,
first_master_relation);IF v_rel_name IS NOT NULL THEN
v_rel_id := FIND_RELATION(v_rel_name);IF GET_RELATION_PROPERTY(v_rel_id, deferred_coordination) =
’FALSE’ THENSET_RELATION_PROPERTY(v_rel_id,deferred_coordination,
property_true);SET_RELATION_PROPERTY(v_rel_id,autoquery,property_true);MESSAGE(’Query-synchronization mode: deferred.’);
ELSESET_RELATION_PROPERTY(v_rel_id,deferred_coordination,
property_false);MESSAGE(’Query-synchronization mode: immediate.’);
END IF;END IF;
END toggle_query_sync;
.
8-18 Oracle iDS Forms: Build Internet Applications II......................................................................................................................................................
......................................................................................................................................................Lesson 8: Controlling Data Block Relationships
Instructor NoteDemonstration: Use Mascmt.fmb to demonstrate Commit Per Master.
Copyright Oracle Corporation, 2001. All rights reserved.®
Forcing a Commit Per Master
Define a procedure that:
• Updates the commit status byperforming validation
• Checks the commit status of the master record
• Raises FORM_TRIGGER_FAILURE incase of changes
Copyright Oracle Corporation, 2001. All rights reserved.®
Forcing a Commit Per Master
Call the procedure:
• In the On-Clear-Details trigger
• Before the “Begin default relationprogram section” comment
Oracle iDS Forms: Build Internet Applications II 8-19......................................................................................................................................................
......................................................................................................................................................Forcing a Commit Per Master
Forcing a Commit Per MasterIn some cases, you must commit changes in master-detail forms before a change of master record takes place, for example, when checking database-level constraints, such as a mandatory relationship.
You must call the procedure below from the On-Clear-Details trigger before the “Begin default relation program section” comment. Note that if the On-Clear-Details trigger fails, the change of master record is aborted.
PROCEDURE check_master_changeIS
v_master_record NUMBER;BEGIN
-- Force update of record status. VALIDATE(record_scope);IF FORM_SUCCESS THEN
-- Check if master record has been modified. v_master_record :=
GET_BLOCK_PROPERTY(NAME_IN(’system.master_block’), current_record);
IF GET_RECORD_PROPERTY(v_master_record, NAME_IN(’system.master_block’),status) IN (’INSERT’, ’CHANGED’) THEN
MESSAGE(’You must commit first before you go to another master record.’);
RAISE form_trigger_failure;END IF;
ELSE-- Validation error.
RAISE form_trigger_failure;END IF;
END check_master_change;
8-20 Oracle iDS Forms: Build Internet Applications II......................................................................................................................................................
......................................................................................................................................................Lesson 8: Controlling Data Block Relationships
Copyright Oracle Corporation, 2001. All rights reserved.®
Summary
In this lesson, you should have learned how to:
• Define Relation coordination properties
• Manage data block coordination
– Coordination-causing events changethe master record
– Clear and populate
Copyright Oracle Corporation, 2001. All rights reserved.®
Summary
• Obtain relation-handling information
– Identify characteristics of relation-handlingtriggers
– Identify characteristics of relation-handlingprocedures
• Coordinate data blocks with REF Elements
Oracle iDS Forms: Build Internet Applications II 8-21......................................................................................................................................................
......................................................................................................................................................Summary
Summary
Creating Relations• Implicitly, when you create a master-detail form module
• Explicitly, by creating the relation after the blocks have been created
Block Coordination• Coordination-causing events cause a change of the master record.
• The two block-coordination phases are the Clear and Populate phases.
• Base coordination of blocks on REF values.
Elements Involved in the Implementation of Block Coordination• The Copy Value from Item property
• Relation-handling triggers and procedures
Characteristics of Relation-Handling Triggers• On-Clear-Details implements the Clear phase.
• On-Populate-Details implements the Populate phase.
• On-Check-Delete-Master implements restricted-delete rules.
Principles of Relation-Handling Code• The three relation-handling procedures are
CLEAR_ALL_MASTER_DETAILS, QUERY_MASTER_DETAILS, and CHECK_PACKAGE_FAILURE.
• Add your own code to relation-handling triggers before or after comments generated by Forms.
Obtaining Relation-Handling Information• There are two system variables for relation handling.
• You can use built-ins for relation handling to get relation names and to get or set relation properties.
8-22 Oracle iDS Forms: Build Internet Applications II......................................................................................................................................................
......................................................................................................................................................Lesson 8: Controlling Data Block Relationships
Copyright Oracle Corporation, 2001. All rights reserved.®
Practice 8 Overview
This practice covers the following topics:
• Examining and changing relation properties
• Implementing a coordination-type toggle for amaster-detail form
• Synchronize coordination-type toggle at formstartup
Oracle iDS Forms: Build Internet Applications II 8-23......................................................................................................................................................
......................................................................................................................................................Practice Overview: Lesson 8
Practice Overview: Lesson 8This practice guides you through choosing the appropriate user-initiated and forms event triggers to implement the desired data block relation functionality.
Practice Contents• Examining and changing relation properties
• Using check boxes to implement a coordination-type toggle for a master-detail form.
- The first check box should enable a user to toggle between immediate coordination and deferred coordination.
- The second check box should enable a user to toggle between auto query and no auto query in the detail block.
• Synchronizing the coordination-type toggle at form startup.
8-24 Oracle iDS Forms: Build Internet Applications II......................................................................................................................................................
......................................................................................................................................................Lesson 8: Controlling Data Block Relationships
Practice 8 1 Open your ORDERS form and examine the properties of the relation
called S_ORD_S_ITEM.
a Note the deletion and coordination property values.
b Run the ORDERS form and test the way deletes are handled.
2 Implement a query coordination-type toggle.
a Add two check boxes to the control block with the following properties:
b Use the Layout Editor to position the check boxes appropriately in the Toolbar canvas.
c Make sure that the first check box enables a user to toggle between immediate coordination and deferred coordination. You can import the code from the pr8_1.txt file.
d Make sure that the second check box enables a user to toggle between automatic query and no automatic query for the detail block. This check box should be disabled if the other check box indicates immediate coordination. You can import the code from the pr8_2.txt file.
e Save, compile, and test your form.
Property Check Box 1 Check Box 2
Name IMMEDIATE AUTO_QUERY
Enabled Yes No
Label Immediate Auto Query
Value When Checked Y Y
Value When Unchecked N N
Check Box Mapping of Other Value
CHECKED UNCHECKED
Keyboard Navigable No No
Mouse Navigate No No
Data Type CHAR CHAR
Initial Value Y Y
DataBase Item No No
Canvas TOOLBAR TOOLBAR
Oracle iDS Forms: Build Internet Applications II 8-25......................................................................................................................................................
......................................................................................................................................................Practice 8
If you have time
3 Synchronize the check boxes at form startup.
a Open your ORDERS form module
b Create a procedure called SYNCHRONIZE_CHECKBOX. This procedure synchronizes the IMMEDIATE and AUTO_QUERY check boxes with the current default value. You can import the code from the pr8_3.txt file.
c Call this procedure from the When-New-Form-Instance trigger.
d Save, compile, and test your module.
8-26 Oracle iDS Forms: Build Internet Applications II......................................................................................................................................................
......................................................................................................................................................Lesson 8: Controlling Data Block Relationships
9-2 Oracle iDS Forms: Build Internet Applications II......................................................................................................................................................
......................................................................................................................................................Lesson 9: Building Multiple Form Applications
Instructor NoteTopic TimingLecture 45 minutesPractice 45 minutes Total 90 minutes
Copyright Oracle Corporation, 2001. All rights reserved.®
Objectives
After completing this lesson, you should be able todo the following:
• Describe the different ways of invokingadditional forms
• Open, call, and close forms
• Navigate between Web-deployedform modules
Copyright Oracle Corporation, 2001. All rights reserved.®
Objectives
After completing this lesson, you should be able todo the following:
• Control opened forms and called forms
• Manage transaction processing foropened forms and called forms
• Choose the most appropriate methodfor invoking forms
• Pass form parameters
Oracle iDS Forms: Build Internet Applications II 9-3......................................................................................................................................................
......................................................................................................................................................Introduction
Introduction
OverviewYou have already seen that Oracle Forms Developer applications frequently consist of more than one form. This lesson revisits the topic of multiple form applications and takes a deeper look into the ways in which one form module can invoke another and the effects this has on transaction processing.
ObjectivesAfter completing this lesson, you should be able to do the following:
• Describe the various ways of invoking additional form modules
• Open, call, and close form modules
• Navigate between Web-deployed form modules
• Control open form modules and called form modules
• Manage transaction processing for open and called form modules
• Choose the most appropriate method for invoking form modules
• Pass form parameters
9-4 Oracle iDS Forms: Build Internet Applications II......................................................................................................................................................
......................................................................................................................................................Lesson 9: Building Multiple Form Applications
Instructor NoteExplain that “different transaction scopes” refers to the SESSION/NO_SESSION parameter of the OPEN_FORM built-in.
Copyright Oracle Corporation, 2001. All rights reserved.®
OPEN_FORM to InvokeAdditional Forms
A B
OPEN_FORM(’form_name’, activate_mode,
session_mode, data_mode, paramlist);
OPEN_FORM(’form_name’, activate_mode,
session_mode, data_mode, paramlist);
• Modeless
• Different transaction scopes
Copyright Oracle Corporation, 2001. All rights reserved.®
Characteristics of OPEN_FORM
• Restricted
• Not valid in Enter Query mode
• No savepoint issued
• Modeless with respect to other opened forms
• Session run time option: FORMS60_SESSION
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......................................................................................................................................................OPEN_FORM to Invoke Additional Forms
OPEN_FORM to Invoke Additional FormsThis built-in procedure opens another form in a modeless fashion; that is, a user can freely switch between open forms. You can open a form within the same transaction scope or within a new transaction scope.
SyntaxOPEN_FORM(’form_name’, activate_mode, session_mode, data_mode, paramlist);
Characteristics of OPEN_FORM• Is a restricted procedure
• Causes opened form to be modeless
• Can start a new database session
Using Data Mode to Share PL/SQL Variable DataYou can use the data mode parameter to share PL/SQL variable data between forms. Create a package that contains the PL/SQL variables to be shared, and place the package in a library. Attach the library to all the forms that are to share the data. In the OPEN_FORM command, set the data_mode parameter to SHARE_LIBRARY_CODE. Any changes made by one form are visible to the other forms. This method of sharing data between forms is preferable to global variables because the PL/SQL variables benefit from PL/SQL’s strong typing and because PL/SQL variables are stored and accessed more efficiently than global variables.
Parameter Description
form_name The file holding the executable module
activate_mode Either ACTIVATE (the default) or NO_ACTIVATE
session_mode Either NO_SESSION (the default) or SESSION
data_mode Either NO_SHARE_LIBRARY_DATA (the default) or SHARE_LIBRARY_DATA
paramlist Either the name (in quotes) or internal ID of a parameter list(This argument is optional.)
9-6 Oracle iDS Forms: Build Internet Applications II......................................................................................................................................................
......................................................................................................................................................Lesson 9: Building Multiple Form Applications
Instructor NoteDemonstration: Use FormFirst.fmb, FormNext.fmb, and FormPost.fmb. Run FormFirst on the Web and use the button toolbar to demonstrate use of OPEN_FORM, CALL_FORM and NEW_FORM, post mode, parameter passing and shared libraries.
Explanation for next page pair (Navigating between Forms):
• Use of NEXT_FORM stops the execution of subsequent statements in the trigger or program unit.
• The When-New-Form-Instance trigger only fires on navigation into a form when the form is initially started.
• The When-Window-Activated trigger should be used for synchronizing forms in a multiple-form application.
Use dept.fmb to open or call emp.fmb in order to illustrate when the triggers fire.
Copyright Oracle Corporation, 2001. All rights reserved.®
Closing Forms
• CLOSE_FORM:
– form_name
– form_id
• Characteristics of CLOSE_FORM:
– Restricted
– Not valid in Enter-Query mode
– CLOSE_FORM or EXIT_FORM
– Cannot close a form that calledanother form
Oracle iDS Forms: Build Internet Applications II 9-7......................................................................................................................................................
......................................................................................................................................................Closing Forms
Closing Forms
SyntaxCLOSE_FORM(form_name);CLOSE_FORM(form_id);
Characteristics of the CLOSE_FORM Procedure• CLOSE_FORM is a restricted procedure that is not valid in Enter Query
mode.
• When the specified form is the current form, CLOSE_FORM is equivalent to EXIT_FORM.
• You cannot close a form that has called another form with CALL_FORM.
Web Design TipThe Oracle Forms Developer application will continue if you attempt to exit your Web-deployed form application by closing the browser window, while other browser windows are still open. It will not terminate until the browser is also closed down. It is recommended that users are always able to close their applications either with the CLOSE_FORM or the EXIT_FORM commands. Applications that are not terminated will continue until timed out by the Oracle Forms Server.
Parameter Description
form_name The module name of the form (not the .fmx filename)
form_id The internal form module ID of the form (of type Form Module)
9-8 Oracle iDS Forms: Build Internet Applications II......................................................................................................................................................
......................................................................................................................................................Lesson 9: Building Multiple Form Applications
Copyright Oracle Corporation, 2001. All rights reserved.®
Navigating Between Forms
Built-ins for navigation between forms:
• NEXT_FORM
• PREVIOUS_FORM
• GO_FORM
Copyright Oracle Corporation, 2001. All rights reserved.®
Navigating Between Forms
Navigation and validation aspects:
• Each open form has a current item.
• There is no validation when navigatingbetween forms.
• No triggers fire when navigatingbetween forms, except the When-Window-Activated/Deactivated andWhen-Form-Navigate triggers.
• Click the noncurrent item in the other form.
Oracle iDS Forms: Build Internet Applications II 9-9......................................................................................................................................................
......................................................................................................................................................Navigating Between Forms
Navigating Between FormsYou can programmatically navigate between multiple forms that have been opened with the OPEN_FORM built-in, just as you can navigate between blocks within one form.
Built-ins for Navigation Between Forms
Navigation and Validation Aspects of Inter-form Navigation• In a multiple-form application, each open form has one item that is the
current item for that form.
• When you are navigating between open forms, no validation occurs in the starting form. When you return to the starting form and attempt to navigate within that form, normal validation is enforced.
• When you are navigating between (current items of) open forms, no triggers fire. The only exceptions are the When-Window-Activated, When-Window-Deactivated, and When-Form-Navigate triggers. Even the navigational triggers do not fire when you are navigating between open forms.
• The triggers that typically fire when you navigate from the current item to the target item will fire when you click a noncurrent item of an open form. When this happens, navigational triggers also fire and validation occurs as required.
Built-in DescriptionNEXT_FORM Navigates to the open form with the next highest sequence number
(Forms are placed in sequence in the order that they were invoked at run time.) If there is no form with a higher sequence number, the built-in navigates to the form with the lowest sequence num-ber.
PREVIOUS_FORM Navigates to the open form with the next lowest sequence number (If there is no form with a lower sequence number, this built-in navigates to the form with the highest sequence number.)
GO_FORM Navigates to the specified form (You can use the form-module name or the form-module ID as the form specification.)
9-10 Oracle iDS Forms: Build Internet Applications II......................................................................................................................................................
......................................................................................................................................................Lesson 9: Building Multiple Form Applications
Copyright Oracle Corporation, 2001. All rights reserved.®
Opening Forms Withinthe Same Session
• Commit processing in all forms withinthe same session, in a certain order
• If error occurs, then focus set toinitiating form
• Messages per open form within thesame session
• CLEAR_FORM usually causes aROLLBACK statement
Copyright Oracle Corporation, 2001. All rights reserved.®
Opening Forms in Different Sessions
Runform Server
Connection
A
B
Session
C
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......................................................................................................................................................Transaction Processing for Opened Forms
Transaction Processing for Opened Forms
Opening Forms Within the Same SessionAt run time, Form Builder automatically establishes a single connection to the Oracle server. By default, one database session is created for this connection. When you open forms within the same session, consider these issues:
• If you issue a commit, all forms will be processed in the order in which they were opened, starting with the current form.
• If an error occurs during commit processing, Form Builder sets the input focus to the form that initiated the commit.
• Commit processing usually causes messages to occur for every open form within the same session. Because Form Builder maintains a message line per open form, a user may have to acknowledge messages from noncurrent open forms. This could be confusing.
• If you issue a CLEAR_FORM command, Form Builder will usually issue a ROLLBACK statement, which rolls back all the changes in the database and releases all locks. However, noncurrent open forms are not cleared.
Opening Forms in Different SessionsThe multiple-session feature of the Oracle server enables a single client to establish multiple database sessions within a single connection. All Oracle server transaction management and read-consistency features are implemented at the session level. Therefore, commit processing, record locking, and read-consistency behavior for two forms in different sessions is the same as it would be for two independent forms with separate connections.
• You can turn the Session option on for all Runtime invocations by setting the FORMS60_SESSION environment variable to True.
• Forms Runtime must be running with the Session option turned on when you execute OPEN_FORM with the SESSION_MODE parameter set to SESSION.
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......................................................................................................................................................Lesson 9: Building Multiple Form Applications
Instructor NoteDemonstration: Use FormFirst.fmb to call FormNext.fmb. Illustrate use of HIDE, NO_HIDE, and QUERY_ONLY arguments
.
Copyright Oracle Corporation, 2001. All rights reserved.®
CALL_FORM to InvokeAdditional Forms
A B
CALL_FORM(‘ form_name’ , display,
switch_menu, query_mode,
data_mode, paramlist);
CALL_FORM(‘ form_name’ , display,
switch_menu, query_mode,
data_mode, paramlist);
• Modal
• Returns to calling form
Copyright Oracle Corporation, 2001. All rights reserved.®
Characteristics of CALL_FORM
• Unrestricted
• Valid in Enter Query mode
• Savepoint issued
• Modal with respect to calling form
• Does not cause navigation and validation
• Forms called from query-only form arealways query-only
• Exiting a called form
Oracle iDS Forms: Build Internet Applications II 9-13......................................................................................................................................................
......................................................................................................................................................CALL_FORM to Invoke Additional Forms
CALL_FORM to Invoke Additional FormsThis built-in procedure calls another form in a modal fashion with respect to the calling form; that is, you cannot work in the calling form. When the called form is exited, Form Builder returns to the calling form.
SyntaxCALL_FORM(’form_name’, display, switch_menu, query_mode, data_mode, paramlist);
Characteristics of CALL_FORM• Is valid in Enter Query mode
• Causes Forms to issue a savepoint
• Causes called form to be modal
• Does not cause navigation or validation in the initial form
• Can call a form in Query Only mode
• Propagates query-only parameter through all subsequent called forms
• Returns control to the calling form and resumes processing of the PL/SQL code at the statement immediately following the calling statement (This occurs when Forms exits the called form.)
Parameter Description
form_name The file holding the executable form module
display Either HIDE (the default) or NO_HIDE (This defines whether the call-ing form should be hidden from view while the called form is running.)
switch_menu Either NO_REPLACE (the default) or DO_REPLACE (This defines whether the current menu module should be replaced by the default menu of the called form.)
query_mode Either NO_QUERY_ONLY (the default) or QUERY_ONLY (This defines whether the called form should run in Query Only mode.)
data_mode Either NO_SHARE_LIBRARY_DATA (the default) or SHARE_LIBRARY_DATA
paramlist Either the name (in quotes) or internal ID of a parameter list(This argument is optional.)
9-14 Oracle iDS Forms: Build Internet Applications II......................................................................................................................................................
......................................................................................................................................................Lesson 9: Building Multiple Form Applications
Instructor NoteDemonstration: Use FormFirst.fmb to call FormPost.fmb in post only mode.
Copyright Oracle Corporation, 2001. All rights reserved.®
Save Not Allowedin Post-Only Mode Form
A calling form has unapplied changes. Save not allowed.
Copyright Oracle Corporation, 2001. All rights reserved.®
Transaction Processingfor Called Forms
• Characteristics of Post-Only mode:
– Commit not allowed, only a post
– Full rollback not allowed, only arollback to savepoint
• Rollback behavior of called forms
• Call savepoints and post savepoints
Oracle iDS Forms: Build Internet Applications II 9-15......................................................................................................................................................
......................................................................................................................................................Transaction Processing for Called Forms
Transaction Processing for Called FormsIf you call forms, you need to understand the commit and rollback processing between the forms.
What Is Post-Only Mode?When a calling form has pending updates or deletes that have not been explicitly posted or committed, Form Builder runs the called form in Post-Only mode. Additionally, any form called from a form running in Post-Only mode is also in Post-Only mode. In Post-Only mode, you can submit DML statements to the database, but you cannot commit the changes. You can only commit the changes after you exit the form that is running in Post-Only mode.
Characteristics of Post-Only Mode If a form runs in Post-Only mode, Forms does not allow certain commit processing operations to prevent losing locks in the calling form.
• A commit is not allowed, only a post. In other words, the changes are written to the database, but a commit statement is not issued. An error message appears on the status line: “A calling form has unapplied changes. Save not allowed.” If a user makes changes in the called form and then exits from the form, Forms usually asks if the user wants to apply (post), rather than Save (commit), the changes that were made.
• A full rollback is not allowed, only a rollback to savepoint.
Rollback Behavior of Called FormsIf a user exits from a called form, Form Builder issues a rollback to the call savepoint that was set when the form was called. This means that all changes posted in the called form are rolled back upon exit from the called form. This is because of the EXIT_FORM built-in default arguments:
EXIT_FORM(ask_commit, to_savepoint);
Do not confuse call savepoints, which are set when a form is called or started, with post savepoints, which are set at the start of a post.
9-16 Oracle iDS Forms: Build Internet Applications II......................................................................................................................................................
......................................................................................................................................................Lesson 9: Building Multiple Form Applications
Copyright Oracle Corporation, 2001. All rights reserved.®
Transaction Processingfor Called Forms
IF <form called> THEN
POST;
ELSE
COMMIT_FORM;
END IF;
IF <form called> THEN
POST;
ELSE
COMMIT_FORM;
END IF;
• Examples of adjusting defaulttransaction processing:
• Key-Commit on form
Copyright Oracle Corporation, 2001. All rights reserved.®
Key-Exit on form
Adjust labels of corresponding buttons and menu items
Transaction Processingfor Called Forms
IF <form called> THEN
EXIT_FORM(ASK_COMMIT, NO_ROLLBACK);
ELSE
EXIT_FORM;
END IF;
IF <form called> THEN
EXIT_FORM
ELSE
EXIT_FORM;
END IF;
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......................................................................................................................................................Transaction Processing for Called Forms
Adjusting Default Transaction Processing for Called FormsThe characteristics of Post-Only mode and the rollback behavior of called forms require that you adjust default transaction processing as follows:
• Redefine [Commit] so that processing performs a post when the form is called.
• Redefine [Exit] so that processing does not perform a rollback when the form is called.
• You may want to adjust the labels of possible buttons and menu items that correspond to [Commit] and [Exit].
ExamplesKey-Commit trigger at form level:
BEGINIF GET_APPLICATION_PROPERTY(calling_form) is not null THEN
POST;ELSE
COMMIT_FORM;END IF;
END;
Key-Exit trigger at form level:BEGIN
IF GET_APPLICATION_PROPERTY(calling_form) is not null THENEXIT_FORM(ask_commit, no_rollback);
ELSEEXIT_FORM;
END IF;END;
9-18 Oracle iDS Forms: Build Internet Applications II......................................................................................................................................................
......................................................................................................................................................Lesson 9: Building Multiple Form Applications
Copyright Oracle Corporation, 2001. All rights reserved.®
NEW_FORM to InvokeAdditional Forms
A B
NEW_FORM(’form_name’, rollback_mode,
query_mode, data_mode,
paramlist);
NEW_FORM(’form_name’, rollback_mode,
query_mode, data_mode,
paramlist);
Replaces calling form
Oracle iDS Forms: Build Internet Applications II 9-19......................................................................................................................................................
......................................................................................................................................................NEW_FORM to Invoke Additional Forms
NEW_FORM to Invoke Additional FormsThis built-in procedure exits from the current form and executes the specified new form. The new form completely replaces the current form.
SyntaxNEW_FORM(’form_name’, rollback_mode, query_mode, data_mode, paramlist);
Web Design TipWith small Web-deployed form modules, you can reduce the time to download your applications from the server. You can easily link Form modules together by using the OPEN_FORM and NEW_FORM built-ins. You can therefore provide users with all the functionality that they require, when they need it.
Parameter Description
form_name The file holding the executable form module
rollback_mode Either TO_SAVEPOINT (the default), NO_ROLLBACK, or FULL_ROLLBACK
query_mode Either NO_QUERY_ONLY (the default) or QUERY_ONLY (This defines whether the called form should run in Query Only mode.)
data_mode Either NO_SHARE_LIBRARY_DATA (the default) or SHARE_LIBRARY_DATA
paramlist Either the name (in quotes) or internal ID of a parameter list(This argument is optional.)
9-20 Oracle iDS Forms: Build Internet Applications II......................................................................................................................................................
......................................................................................................................................................Lesson 9: Building Multiple Form Applications
Technical NoteYou can obtain information about the call form stack by using the GET_APPLICATION_PROPERTY built-in with the CALLING_FORM parameter.
Instructor NoteThe slide illustrates the restrictions on using OPEN_FORM and CALL_FORM.In this scenario, Form A calls Form B, Form B then opens Form C, Form C then opens Form D; and Form B then calls Form E.
• The call is not allowed to navigate to Forms A and B.
• The current call form stack consists of Forms A, B, and E.
• A form cannot be called from Form C and D.
• Changes in any form are rolled back to the savepoint (S.P.) that was set when Form E was called.
Copyright Oracle Corporation, 2001. All rights reserved.®
Controlling Openedand Called Forms
Form A
S.P. CALL_FORM
Form B
Form C
OPEN_FORM
Form DOPEN_FORM
S.P. CALL_FORM
Form E
Form F
CALL_FORM
Form A+B+E = Call form stack
Oracle iDS Forms: Build Internet Applications II 9-21......................................................................................................................................................
......................................................................................................................................................Controlling Open Forms and Called Forms Together
Controlling Open Forms and Called Forms TogetherWhen you invoke multiple forms with OPEN_FORM and CALL_FORM in the same application, you should be aware of certain restrictions.
Call Form StackWhen you call a form with CALL_FORM, the calling form is disabled until the operator exits from the called form. However, a called form can in turn call other forms. When successive forms are loaded by way of CALL_FORM in this way, the resulting form hierarchy is known as the call form stack.
Restrictions on Using OPEN_FORM with CALL_FORM• Navigation: Any attempt to navigate programmatically to a disabled
form in a call form stack is disallowed.
• Calling forms: An open form cannot execute the CALL_FORM built-in if a call form stack has been initiated by another open form. In other words, you can have only one call form stack per Runform session.
• Rollback: Forms issues a savepoint when calling a form with CALL_FORM. Any subsequent rollback, in any form, rolls back only the changes that were made since this savepoint.
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......................................................................................................................................................Lesson 9: Building Multiple Form Applications
Instructor NoteWith use of WEB.SHOW_DOCUMENT you are able to navigate between opened forms by using the browser BACK and FORWARD buttons. This command is covered in a later lesson.
Copyright Oracle Corporation, 2001. All rights reserved.®
Different Ways of Invoking Forms
• When to use OPEN_FORM
• When to open a form in a new session
• When to use CALL_FORM
• When to use NEW_FORM
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......................................................................................................................................................Different Ways of Invoking Forms
Different Ways of Invoking Forms
When to Use OPEN_FORMOPEN_FORM is the preferred method of invoking another form. Because open forms are modeless, a user can freely switch between them. OPEN_FORM is most appropriate for invoking forms from the application-system menu. A drawback of OPEN_FORM is that it may be difficult to keep multiple open forms synchronized. For example, you may want the current order in an ORDERS form always to belong to the current customer in a CUSTOMERS form.
When to Open a Form in a New SessionCreating new sessions is usually appropriate for forms that manage transactions that are logically independent. If the open forms act on tables that are closely related, data manipulation of all those forms could be considered part of one transaction. Therefore, the forms should be opened in the same session.
Note: You can also consider using CALL_FORM in this situation.
When to Use CALL_FORMUse CALL_FORM if you want the invoked form to be modal. This is appropriate if the invoked form is used to set data in the invoking form; for example, in the case of an LOV form. Another reason may be that you want to make it easier to keep the invoking and invoked forms synchronized.
When to Use NEW_FORMThe main advantage of this built-in is that it conserves memory because the invoked form replaces the invoking form.
Web Design TipAdditional forms may be opened within a Web-deployed form by using the built-in WEB.SHOW_DOCUMENT. With this command you must specify a URL to call another form. An additional Forms run-time session, however, will be generated.In order to run many forms within one Web-deployed Forms run-time session, use OPEN_FORM, CALL_FORM or NEW_FORM.
Calling forms will impose a burden on client and Web Server memory. If it is unlikely that the user will return to the calling form, (such as a login form), use NEW_FORM. If the user will continue to use the calling form, then OPEN_FORM will save the startup delay and use of network resources that reloading the form would otherwise incur.
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......................................................................................................................................................Lesson 9: Building Multiple Form Applications
Copyright Oracle Corporation, 2001. All rights reserved.®
Using Form Parameters
• What is a form parameter?
• How to create a form parameter
Copyright Oracle Corporation, 2001. All rights reserved.®
Passing Values to a Form
P1
P2
P3
Runform
command line
Design-timeparameters
Form B
Parameterlist
OPEN_FORMCALL_FORMNEW_FORM
Form A
Run time
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......................................................................................................................................................Using Form Parameters
Using Form Parameters
What Is a Form Parameter?Form parameters provide a mechanism for supplying values that a form requires at startup. These parameters are form variables that you define at design time.
Creating a Form Parameter1 In the Object Navigator, create a parameter.
2 In the Property Palette window for the parameter, set the desired values for Name, Subclass Information, Parameter Data Type, Maximum Length, Parameter Initial Value, and Comments.
Passing Parameter Values to a FormYou can start a form from the command line or invoke it from another form. In both cases, you can specify values for form parameters.
• Specify the parameters on the Runtime command line.
• Programmatically assign the parameters to a parameter list and specify the parameter list in the call to OPEN_FORM, CALL_FORM, or NEW_FORM.
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......................................................................................................................................................Lesson 9: Building Multiple Form Applications
Instructor NoteDemonstration: Use FormFirst.fmb to demonstrate communication with Form Parameters and also with Shared Libraries (Passvalues.pll). Switch toolbars in FormFirst.fmb to open FormNext with parameters or shared library values.
Copyright Oracle Corporation, 2001. All rights reserved.®
ifrun60 module=orditem userid=scott/tiger cus_id=202
Using Form Parameters
• Passing a form parameter at run time:
• Referencing form parameters fromwithin a module:
– :PARAMETER. parameter_name
– ‘PARAMETER. parameter_name’
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......................................................................................................................................................Using Form Parameters
ExamplePass a value for the CUS_ID form parameter to the ORDITEM form by way of the Runtime command line. Note that MODULE and USERID are predefined command line parameters.
ifrun60.exe module=orditem userid=scott/tiger cus_id=202
Referencing Form ParametersYou can reference form parameters in a way similar to how you would access Forms variables.
• To reference the parameter contents, use bind-variable syntax: :PARAMETER.parameter_name, where the reserved word PARAMETER is the fixed part.
• To reference the parameter name, put the fully qualified name between single quotation marks: ‘PARAMETER.parameter_name’
ExampleAssign the value of the CUS_ID form parameter to the CUSTOMER_ID item in the ORDER block.
:order.customer_id := :PARAMETER.cus_id;
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......................................................................................................................................................Lesson 9: Building Multiple Form Applications
Technical NoteThe parameters whose values are being passed must be defined in the called form at design time. That is, the called form must be expecting a value for each of the parameters included in the parameter list it receives from the calling form.
Copyright Oracle Corporation, 2001. All rights reserved.®
OPEN_FORM( …, )
CALL_FORM( …, )
NEW_FORM( …, )
Parameter Lists
CUS_ID
ORDERS
TEXT_PARAMETER
DATA_PARAMETER
‘204’
‘RG_ORD’
Parameterlist
The default parameter list is DEFAULT
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......................................................................................................................................................Parameter Lists
Parameter ListsOne way to supply form parameter values is to specify a parameter list in the call to the built-in that invokes the form.
What Is a Parameter List?A parameter list is a named programmatic construct that lists parameter names (called keys), their types, and their values. You can specify parameter lists in the calls to the following built-ins:
• CALL_FORM
• OPEN_FORM
• NEW_FORM
• RUN_PRODUCT
Two Parameter Types
Default Parameter List Each form includes a built-in parameter list named DEFAULT. The DEFAULT parameter list contains all of the form parameters that were defined in the form at design time. Like any other parameter list, the DEFAULT parameter list can be specified in the call to the built-ins that can invoke a form.
Type DescriptionText Parameter A simple parameter with a scalar, noncomposite CHAR value.
You must use this type of parameter, unless you want to pass a record group to another Oracle product.
Data Parameter A parameter whose value must always be the name of a record group defined in the current form. Data parameters are used to pass data to products invoked with the RUN_PRODUCT built-in. You cannot pass data parameters to forms.
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......................................................................................................................................................Lesson 9: Building Multiple Form Applications
Technical NoteYou cannot create a parameter list named DEFAULT or one that already exists. Use GET_PARAMETER_LIST and ID_NULL to check whether a parameter list already exists.
Copyright Oracle Corporation, 2001. All rights reserved.®
Name
Parameter
list ID
Creating and ManipulatingParameter Lists
ADD_PARAMETER
GET_PARAMETER_ATTR
SET_PARAMETER_ATTR
DELETE_PARAMETER
CUS_ID
ORDERS
TEXT_PARAMETER
DATA_PARAMETER
‘204’
‘RG_ORD’
DESTROY_PARAMETER_LIST
Key Type ValueCREATE_PARAMETER_LIST
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......................................................................................................................................................Creating and Manipulating Parameter Lists
Creating and Manipulating Parameter ListsYou can programmatically create and manipulate parameter lists only by using the following built-ins:
Built-in DescriptionCREATE_PARAMETER_LIST Creates a parameter list with the given name and
returns the ID of this parameter listDESTROY_PARAMETER_LIST Deletes the given, programmatically created
parameter list (and all its parameters)GET_PARAMETER_LIST Returns the internal parameter list ID (of type
PARAMLIST) of a parameter list with the given name (This built-in is similar to the FIND_object built-ins.)
ADD_PARAMETER Adds a parameter with a specified name (also called key), type (TEXT_PARAMETER or DATA_PARAMETER), and value (in CHAR for-mat) to the given parameter list
DELETE_PARAMETER Deletes the parameter with the specified name from the given parameter list
GET_PARAMETER_ATTR Gets the type and value of the parameter with the specified name in the given parameter list
SET_PARAMETER_ATTR Sets the type and value of the parameter with the specified name in the given parameter list
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......................................................................................................................................................Lesson 9: Building Multiple Form Applications
Technical NoteGlobal variables are used more often than parameters for passing data between forms.
Copyright Oracle Corporation, 2001. All rights reserved.®
Passing Data Between Forms
P1
P2
P3
P1
P2
P3
OPEN_FORM(*)
1. If a parameter list exists, destroy it.2. Create a parameter list.3. Add a text parameter to a list with the value
of an item.4. Open a form with this parameter list.
Design-timeparameters
Form B
Run timeparameters
Form A
Copyright Oracle Corporation, 2001. All rights reserved.®
Passing Data Between Forms
• Characteristics of form parameters:
– Can be used only as input parameters
– Have data type CHAR, NUMBER, or DATE
– CHAR parameter can be up to 64 K long
– Can be design-time objects
• Characteristics of global variables:
– Are programmatic constructs
– Have type CHAR(255)
– Are visible to all forms in the currentRunform session
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......................................................................................................................................................Passing Data Between Forms
Passing Data Between FormsYou can pass data to other forms by using form parameters, as shown in the following example. The next section compares this approach with the global variable approach.
ExampleThe When-Button-Pressed trigger on the CTL.OPEN_ORDITEM item:
DECLAREv_pl_id PARAMLIST;
BEGINIF not ID_NULL(GET_PARAMETER_LIST(’cus’)) THEN
DESTROY_PARAMETER_LIST(’cus’);END IF;v_pl_id := CREATE_PARAMETER_LIST(’cus’);ADD_PARAMETER(v_pl_id,’cus_id’,text_parameter,
TO_CHAR(:cus.id));OPEN_FORM(’orditem’, activate, no_session,
no_share_library_data, ’cus’);END;
Note: You must define the CUS_ID parameter in the ORDITEM form at design time, because each run-time parameter must have a corresponding design-time parameter in the target form.
Form Parameters and Global Variables• Form parameters can be used only as input parameters; the invoked form
cannot return modified form-parameter values to the invoking form. Therefore, global variables are the preferred method for communicating between forms.
• Advantages of form parameters include:
- They have a data type of CHAR, NUMBER, or DATE.
- The length of a CHAR parameter can be up to 64 K.
- They can be design-time objects.
- Global variables are always programmatic constructs of type CHAR(255). They are visible to all the forms in the current Runform session.
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......................................................................................................................................................Lesson 9: Building Multiple Form Applications
Copyright Oracle Corporation, 2001. All rights reserved.®
Summary
In this lesson, you should have learned how to:
• Open, call, and close forms:
– OPEN_FORM, CALL_FORM, andCLOSE_FORM
– Multiple database sessions
• Navigate between forms:
– NEXT_FORM,PREVIOUS_FORM, and GO_FORM
• Identify restrictions on the call form stack
Copyright Oracle Corporation, 2001. All rights reserved.®
Summary
• Manage Transaction processing in:
– Opened forms: Within same ordifferent sessions
– Called forms: Post-Only mode; arollback to savepoint
• Create form parameters and parameter lists
– Methods for parameter passing
– Referencing form parameters
– Text parameters and Data parameters
– Built-ins for parameter lists
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......................................................................................................................................................Summary
Summary
The Three Built-ins for Invoking Forms• OPEN_FORM
• CALL_FORM
• NEW_FORM
Opening, Calling, and Closing Forms• OPEN_FORM
• CALL_FORM
• CLOSE_FORM
Built-ins for Navigation Between Forms• NEXT_FORM
• PREVIOUS_FORM
• GO_FORM
Controlling Open Forms and Called Forms Together Restrictions on the call form stack
Transaction Processing for Open FormsWithin the same session or different sessions
Transaction Processing for Called Forms• Characteristics of Post-Only mode
• Rollback behavior of called forms: default rollback to savepoint
Using Form Parameters• Passing parameter values to a form by way of Runform command line or
parameter list
• Referencing form parameters using PARAMETER.parameter_name
Using Parameter Lists• The two parameter types: text parameters and data parameters
• The default parameter list named DEFAULT
• Built-ins for creating and manipulating parameter lists
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......................................................................................................................................................Lesson 9: Building Multiple Form Applications
Copyright Oracle Corporation, 2001. All rights reserved.®
Practice 9 Overview
This practice covers the following topics:
• Implementing a multiple form application bycalling SALESREP from CUSTOMERS
• Performing an automatic query onthe SALESREP form, based on theSales Rep ID value in the CUSTOMER form
• Ensuring that posted changes inSALESREP are not rolled back
• Passing a parameter list from CUSTOMERSto SALESREP
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......................................................................................................................................................Practice Overview: Lesson 9
Practice Overview: Lesson 9This practice guides you through managing several interacting forms within one application.
Practice ContentsImplement a button on the CUSTOMER form to call the SALESREP form.
• Perform an automatic query on the SALESREP form based on the current sales rep ID in the CUSTOMER form.
• Ensure that posted changes in the SALESREP form are not rolled back on exit.
• Pass a parameter list from the CUSTOMERS form to the SALESREP form.
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......................................................................................................................................................Lesson 9: Building Multiple Form Applications
Practice 9 1 Create a multiple-form application by linking the CUSTOMERS and the
SALESREP forms. The SALESREP form provides a look up facility for :S_CUSTOMER.SALES_REP_ID. It replaces the SALES_REP_LOV list of values. Values are selected by mouse double click.
a Open SALESREP form and save as SALESREPXX where XX is your student course number.
b In your CUSTOMERS form, modify the code in the SALES_LOV_BUTTON When-Button-Pressed trigger to call the SALESREP form.
c Ensure that the user can see, but not navigate to, your CUSTOMERS form, while the SALESREP form is open.
d Update :S_CUSTOMER.SALES_REP_ID with the value selected by the user in the SALESREP form. The selected Sales Rep ID is returned in a GLOBAL variable called “salesrepid”. This variable contains either a valid value or the text “NOT SELECTED”.
e Save and compile your form. Deploy your form to the Web to test.
2 Modify your multiple-form application to enable the SALESREP form to be called in post mode only.
a Hide the CUSTOMERS form when the SALESREP form is displayed.
b In the SALESREP form, ensure that whenever the form has been opened by ‘CALL_FORM’, that a [Commit Form] performs a POST.
c Ensure that updates in SALESREP are not cleared when the user exits the form.
d Save and compile your form. Deploy your form to the Web to test.
3 The SALESREP form displays a list of all employees; modify your application to ensure that only Sales Representatives are displayed when the form is called from CUSTOMERS.
a Create a parameter called ‘EVERYONE’ in the SALESREP form. Specify a default value of ‘Y’.
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......................................................................................................................................................Practice 9
b Ensure that the SALESREP form will perform an unrestricted query whenever the parameter value = ‘Y’. If the parameter value = ‘S’, a restricted query should be performed, selecting only Sales Representatives.
c In the CUSTOMERS form, pass the parameter value “S” to the SALESREP form. Create a parameter list called EMPS. Add the ‘EVERYONE’ parameter to the parameter list. The type of this parameter is TEXT_PARAMETER, and it is initialized with the value “S”.Pass the parameter list to the SALESREP form by using the CALL_FORM built-in.You can import the code from the pr9_1.txt file. Be sure to change the name of the module in the CALL_FORM built-in.
d Save and compile your forms. Deploy your form to the Web to test.
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......................................................................................................................................................Lesson 9: Building Multiple Form Applications
10-2 Oracle iDS Forms: Build Internet Applications II......................................................................................................................................................
......................................................................................................................................................Lesson 10: Working with Record Groups
Instructor NoteTopic TimingLecture 50 minutes
Practice 30 minutes
Total 80 minutes
Copyright Oracle Corporation, 2001. All rights reserved.®
Objectives
After completing this lesson, you should be able todo the following:
• Describe the record group object
• Use record groups
• Define record groups at design time
• Control record groups by using built-in functions
• Define query record groups programmatically
• Define nonquery record groups programmatically
Copyright Oracle Corporation, 2001. All rights reserved.®
Objectives
After completing this lesson, you should be able todo the following:
• Manipulate record group rows
• Define lists of values (LOVs) programmatically
• Manipulate list items programmatically
• Implement dynamic list items
• Add values to combo boxes
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......................................................................................................................................................Introduction
Introduction
OverviewRecord groups are useful constructs for storing structured data, and they can be manipulated at run time. This lesson covers how to create, modify, and delete record groups at design time and programmatically at run time. It also covers how you apply record groups in useful ways, such as for dynamic list items.
ObjectivesAfter completing this lesson, you should be able to do the following:
• Describe the record group object
• Use record groups
• Define record groups at design time
• Control record groups by using built-in functions
• Define query record groups programmatically
• Define nonquery record groups programmatically
• Manipulate record group rows
• Define lists of values (LOVs) programmatically
• Manipulate list items programmatically
• Implement dynamic list items
• Add values to combo boxes
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......................................................................................................................................................Lesson 10: Working with Record Groups
Copyright Oracle Corporation, 2001. All rights reserved.®
Record Groups
Three record group types:
Design Time
Run Time
SOURCE
TIME
Based on aSELECT
Statement
Not Based on aSELECT
Statement
QUERY
QUERY
STATIC
NON QUERY
Copyright Oracle Corporation, 2001. All rights reserved.®
Record Groups
Record groups and LOVs
• Forms implicitly creates query record groups.
• Use SET_LOV_PROPERTY to replacedefault record group.
...
IF Get_LOV_Property(lov_id,GROUP_NAME) = ’GROUP1’
THEN
Set_LOV_Property(lov_id,GROUP_NAME,’GROUP2’);
END IF;
...
...
IF Get_LOV_Property(lov_id,GROUP_NAME) = ’GROUP1’
THEN
Set_LOV_Property(lov_id,GROUP_NAME,’GROUP2’);
END IF;
...
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......................................................................................................................................................Record Groups
Record Groups
What Is a Record Group?A record group is an internal Forms data structure that is similar to a database table. It can have columns of type CHAR, NUMBER, or DATE, and its data is stored in rows. Record groups exist in local Forms memory, rather than in the database.
Three Record Group Types
Note: When you create a record group, you cannot specify its type explicitly. The type is implied by when and how you create the record group.
Record Groups and LOVsWhen you create a list of values (LOV) based on a query, Form Builder implicitly creates a query record group. In this case, the columns and rows of the record group are determined by the LOV SQL query statement. At run time, you can call the SET_LOV_PROPERTY built-in function to replace the default record group of an LOV with another one. Use the GROUP_NAME property.
Type DescriptionQuery Record Group A record group with an associated SELECT statement. The
columns in the record group derive their properties from the columns in this SELECT statement. The rows in the record group are the rows retrieved by this SELECT statement. You can create this type of record group at design time and at run time.
Nonquery Record Group A record group without an associated query. The columns and rows of the record group are defined programmatically at run time and can also be modified at run time.
Static Record Group A record group without an associated query. The columns and rows of the record group are defined at design time and cannot be modified programmatically at run-time.
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......................................................................................................................................................Lesson 10: Working with Record Groups
Copyright Oracle Corporation, 2001. All rights reserved.®
Uses for Record Groups
• Constructing dynamic SELECT statements
• Storing form-configuration information
• Communicating within a form
• Passing data to other forms
• Passing data to other Oracle products
• Populating or storing list items
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......................................................................................................................................................Using Record Groups
Using Record GroupsRecord groups are very powerful constructs offered by Oracle Forms Developer. Some useful record group applications are listed below.
Constructing Dynamic SELECT StatementsThe SELECT statement on which a query record group is based can be constructed programmatically at run time. As a consequence, you can write very generic program units; for example, accepting a table name as parameter.
Storing Form-Configuration InformationBecause a record group is a structured data type, you can use it as a convenient means for storing information about the current form. Such information may describe the way in which the form is set up or configured, and is usually retrieved at form startup.
Communicating Within a FormBecause a record group is a structured data type, you can use it to exchange related data within a form. For example, different program units or different invocations of the same program unit might access the record group data. This offers you an alternative to a set of scalar variables, such as help items or global variables.
Passing Data to Other FormsYou can create a global record group at run time that is visible to all forms in an application.
Passing Data to Other Oracle ProductsYou can use the RUN_PRODUCT built-in to pass data by way of a record group to another Oracle product, specifically Report Builder and Graphics Builder. This eliminates the need to perform a query again in the other Oracle product if it has already been executed by Forms.
Populating or Storing List ItemsYou can transfer the values of a record group to a list item. Because the record group may be based on a dynamically constructed SELECT statement, this ability gives you the opportunity to create dynamic list items. The data transfer is bidirectional; you can also transfer the values of a list item to a record group. (This can be considered “storing” the list item.)
10-8 Oracle iDS Forms: Build Internet Applications II......................................................................................................................................................
......................................................................................................................................................Lesson 10: Working with Record Groups
Instructor NoteDemonstration: Use rec_grp.fmb to demonstrate how you create query record groups (CUSTOMER_ID) and static record groups (STATIC_GROUP).
Copyright Oracle Corporation, 2001. All rights reserved.®
Defining Record Groupsat Design Time
Copyright Oracle Corporation, 2001. All rights reserved.®
Column Specification and Record GroupProperty Sheet
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......................................................................................................................................................Defining Record Groups at Design Time
Defining Record Groups at Design Time
Creating a Query Record Group1 In the Object Navigator, create a record group.
Forms displays the New Record Group dialog box.
2 Click the Based on the Query Below... option button and then enter a SELECT statement in the Query Text field.
3 Click OK. Forms validates the SELECT statement and closes the dialog box.
Note: Use column aliases for expressions in the SELECT clause. Otherwise, Forms generates an unreadable name for the corresponding column of the record group.
Creating a Static Record Group1 In the Object Navigator, create a record group.
Forms displays the New Record Group dialog box.
2 Click the Static Values radio button and then click OK.Forms displays the Column Specification dialog box.
3 Enter the names of the columns in the Column Name list.
4 Specify the Data Type, Length, and Column Values properties for each column.Note that these properties apply to the column currently selected in the Column Name list.
5 Click OK to accept the record group definition.
Modifying the SELECT Statement of a Query Record Group1 In the Object Navigator, select the desired record group.
2 In the Properties window, call the Editor from the Record Group Query property.
3 Modify the SELECT statement as desired and then click OK.
Modifying the Column Definitions of a Record Group1 In the Object Navigator, select the desired record group.
2 In the Properties window, double-click the Column Specifications property. Forms displays the Column Specification dialog box.
3 Select a column and modify its Data Type, Length, and Column Values properties as desired and then click OK.
10-10 Oracle iDS Forms: Build Internet Applications II......................................................................................................................................................
......................................................................................................................................................Lesson 10: Working with Record Groups
Instructor NotePoint out that CREATE_GROUP_FROM_QUERY does not populate the record group. ADD_GROUP_ROW adds an empty row. Row No is an internal number.
Copyright Oracle Corporation, 2001. All rights reserved.®
Creating and Deleting Record Groups
CREATE_GROUP CREATE_GROUP_FROM_QUERY
Recordgroup ID
Recordgroup ID
ID Name
DELETE_GROUP
Name, QueryName
Copyright Oracle Corporation, 2001. All rights reserved.®
Modifying the Structure
ADD_GROUP_ROW
DELETE_GROUP_ROW
Row No ID Name Address1 201 Unisports23 203 Delhi Sports4 204 Womansport
ADD_GROUP_COLUMN
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......................................................................................................................................................Built-in Functions for Controlling Record Groups
Built-in Functions for Controlling Record GroupsYou can create and modify query and nonquery record groups programmatically at run time by using the following built-in functions.
Creating and Deleting Record Groups
Modifying the Structure of Record Groups
Built-in Function DescriptionCREATE_GROUP Creates a nonquery record group with the given
name and returns the ID of this record groupCREATE_GROUP_FROM_QUERY Creates a query record group with the given
name based on the given SELECT statement and returns the ID of this record group (Note that this built-in function does not populate the record group.)
DELETE_GROUP Deletes the given, programmatically created record group
Built-in Function DescriptionADD_GROUP_COLUMN Adds a column of the specified data type (and
column width for CHAR columns) to the given record group and returns the ID of this group column
ADD_GROUP_ROW Adds a row with the specified row number to the given record group
DELETE_GROUP_ROW Deletes the specified row or all rows of the given record group
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......................................................................................................................................................Lesson 10: Working with Record Groups
Technical NotePOPULATE_GROUP built-in function returns 0 when population succeeds and 1 if population does not succeed.
Copyright Oracle Corporation, 2001. All rights reserved.®
Populating Query Record Groups
ID Name201 Unisports202 SImms Athletics203 Delhi Sports204 Womansport
POPULATE_GROUP
(_WITH_QUERY)
SELECT ID, name
FROM s_customer
Copyright Oracle Corporation, 2001. All rights reserved.®
Getting and Setting RecordGroup Cell Values
SET_GROUP_CHAR_CELL
GET_GROUP_NUMBER_CELL
ID Name
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......................................................................................................................................................Built-in Functions for Controlling Record Groups
Populating Record Groups
Note: You can convert a nonquery record group into a query record group by using the POPULATE_GROUP_WITH_QUERY built-in function to populate the nonquery record group.
Getting Record Group Cell Values
Built-in Function DescriptionPOPULATE_GROUP Executes the query associated with the given
query record group and returns a number indicating success or failure (The retrieved rows replace any existing rows in the record group.)
POPULATE_GROUP_WITH_QUERY Executes the specified SELECT statement for the given record group and returns a number indicating success or failure (The retrieved rows replace any existing rows in the record group.)
SET_GROUP_CHAR_CELL, SET_GROUP_DATE_CELL,SET_GROUP_NUMBER_CELL
Sets the value for the record group cell identified by the given record group column and row number (The record group column must be of data type VARCHAR2 or LONG, DATE, or NUMBER, respectively.)
Built-in Function DescriptionGET_GROUP_CHAR_CELL, GET_GROUP_DATE_CELL, GET_GROUP_NUMBER_CELL
Returns the value for the record group cell identified by the given record group column and row number (The record group column must be of data type VARCHAR2 or LONG, DATE, or NUMBER, respectively.)
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......................................................................................................................................................Lesson 10: Working with Record Groups
Instructor NoteExplain the built-ins and describe how with SET_GROUP_SELECTION, if you select rows 2 and 4, the associated selection numbers are 1 and 2. Explain that the record group type (query, nonquery, static) and time of creation (design time or run time) determine which built-in functions are valid for a particular record group.
Copyright Oracle Corporation, 2001. All rights reserved.®
GET_GROUP_SELECTION_COUNT
SET_GROUP_SELECTIONGET_GROUP_SELECTION
Selection No Row No1
1 23
2 4
Processing Record Group Rows
ID Name201 Unisports202 Simms Athletics203 Delhi Sports204 Womansport
GET_GROUP_ROW_COUNT
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......................................................................................................................................................Built-in Functions for Controlling Record Groups
Processing Record Group Rows
Finding Record Group Objects
Built-in Function DescriptionGET_GROUP_ROW_COUNT Returns the number of rows in the given
record groupSET_GROUP_SELECTION Marks the specified row in the given record
group by associating a selection number with the row
UNSET_GROUP_SELECTION Deselects the row with the specified row number in the given record group
RESET_GROUP_SELECTION Deselects all selected rows in the given record group
GET_GROUP_SELECTION_COUNT Returns the number of selected rows in the given record group
GET_GROUP_SELECTION Returns the row number of the row with the specified selection number of the given record group
Built-in Function DescriptionFIND_GROUP Returns the internal record group ID (of type RECORDGROUP)
of a record group with the given name (This function can also be used for record groups created at design time.)
FIND_COLUMN Returns the internal group column ID (of type GROUPCOLUMN) of a record group column with the given name (Note that this name must include the record group name as a prefix. This function can also be used for group columns created at design time.)
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......................................................................................................................................................Lesson 10: Working with Record Groups
Instructor NoteDemonstration: Use rec_grp.fmb to demonstrate the code for creating a query record group. Use the procedure DEFINE_QUERY_RECORD_GROUP.
Copyright Oracle Corporation, 2001. All rights reserved.®
Defining Query Record GroupsProgrammatically
Find record group
Yes ID NULL? No
Create group from query
Populate group
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......................................................................................................................................................Defining Query Record Groups Programmatically
Defining Query Record Groups ProgrammaticallyThe PL/SQL code below illustrates how you can create and populate a query record group.
Note: The query record groups can also be defined at design time.DECLAREv_rg_id RECORDGROUP;v_errcode NUMBER;
BEGIN--Make sure that record group doesn’t already exist.v_rg_id := FIND_GROUP(’customers’);IF ID_NULL(v_rg_id) THEN
--Create query record group.v_rg_id := CREATE_GROUP_FROM_QUERY(’customers’,
’SELECT id, name FROM s_customer ORDER BY id’);END IF;--Populate query record group with associated query.v_errcode := POPULATE_GROUP(v_rg_id);
END;
You can replace the associated query of a query record group by calling the POPULATE_GROUP_WITH_QUERY built-in function.
v_errcode := POPULATE_GROUP_WITH_QUERY(v_rg_id,’SELECT id, name FROM s_customerwhere region_id = 1 ORDER BY id’);
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......................................................................................................................................................Lesson 10: Working with Record Groups
Instructor NoteDemonstration: Use rec_grp.fmb to demonstrate the code for creating a nonquery record group.
Use the procedure DEFINE_NON_QUERY_RECORD_GROUP.
Copyright Oracle Corporation, 2001. All rights reserved.®
Yes ID NULL? No
Defining Nonquery Record GroupsProgrammatically
Find record group
Create group Delete group rows
Add group columns Find group columns
Add group row
Set group cell values
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......................................................................................................................................................Defining Nonquery Record Groups Programmatically
Defining Nonquery Record Groups ProgrammaticallyThe PL/SQL code below illustrates how you can create and populate a nonquery record group. Note that you cannot define nonquery record groups at design time.
DECLAREv_rg_id RECORDGROUP;v_gc1_id GROUPCOLUMN;v_gc2_id GROUPCOLUMN;
BEGIN--Make sure that record group doesn’t already exist.v_rg_id := FIND_GROUP(’customers’);IF ID_NULL(v_rg_id) THEN
--Create non-query record group.v_rg_id := CREATE_GROUP(’customers’);--Add NUMBER and CHAR group column to record group.v_gc1_id := ADD_GROUP_COLUMN(v_rg_id,’id’,number_column);
v_gc2_id := ADD_GROUP_COLUMN(v_rg_id,’name’,char_column,50);ELSE
--Delete all existing group rows.DELETE_GROUP_ROW(v_rg_id,all_rows);--Find ids of group columns for later use.v_gc1_id := FIND_COLUMN(’customers.id’);v_gc2_id := FIND_COLUMN(’customers.name’);
END IF;--Add one group row to record group.ADD_GROUP_ROW(v_rg_id,1);--Fill r g cells of group row 1 with item values.SET_GROUP_NUMBER_CELL(v_gc1_id,1,:cus.id);SET_GROUP_CHAR_CELL(v_gc2_id,1,:cus.name);
END;
You can convert the nonquery record group into a query record group by calling the POPULATE_GROUP_WITH_QUERY built-in function.
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......................................................................................................................................................Lesson 10: Working with Record Groups
Instructor NoteDemonstration: Use rec_grp.fmb to demonstrate the code for manipulating record group rows. Use the GET_VALUE_GRPROW function to show the code that you use to search for a specific value in a record group.
Explain that this technique can be used with a combo box to determine whether or not the value already exists in the record group.
Copyright Oracle Corporation, 2001. All rights reserved.®
Manipulating Record Group Rows
Get number of group rows
For allgrouprows
Cell value=given value
Yes No
Return rownumber
Return NULL
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......................................................................................................................................................Manipulating Record Group Rows
Manipulating Record Group RowsThe function below illustrates how you can loop through all rows of a record group.
FUNCTION get_value_grprow/* Returns row number of group row that contains the
specified value in the given group column.
Returns NULL if the value is not found. */( p_rg_id in RECORDGROUP,p_gc_id in GROUPCOLUMN,
p_value in VARCHAR2)RETURN number IS
v_grprow_count NUMBER;BEGIN
v_grprow_count := GET_GROUP_ROW_COUNT(p_rg_id);FOR v_grprow_no IN 1 .. v_grprow_count LOOP
IF GET_GROUP_CHAR_CELL(p_gc_id,v_grprow_no) = p_value THENRETURN(v_grprow_no);
END IF;END LOOP;RETURN(null);
END;
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......................................................................................................................................................Lesson 10: Working with Record Groups
Instructor NoteDemonstration: Use rec_grp.fmb to demonstrate the code for manipulating selected record group rows.
Use the SELECT_EVEN_ROWS procedure to show the code for searching for a specific row in a record group.
Use the GET_VALUE_GRPSEL function to show the code for looping through the row in a record group.
Explain that the even number can be identified by using the MOD function.
Copyright Oracle Corporation, 2001. All rights reserved.®
For allgrouprows
Manipulating Selected Record GroupRows
Get number of group rows
Row numbereven?
Yes No
Mark rowas selected
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......................................................................................................................................................Manipulating Selected Record Group Rows
Manipulating Selected Record Group RowsThe following procedure illustrates how you can select the rows of a record group.
PROCEDURE select_even_rows--Marks all group rows with even row numbers as selected. (p_rg_id in RECORDGROUP)
ISv_grprow_count NUMBER;
BEGINv_grprow_count := GET_GROUP_ROW_COUNT(p_rg_id);FOR v_grprow_no IN 1 .. v_grprow_count LOOPIF MOD(v_grprow_no,2) = 0 THENSET_GROUP_SELECTION(p_rg_id,v_grprow_no);
END IF;END LOOP;
END;
The function below illustrates how you can loop through all selected rows of a record group.
FUNCTION get_value_grpsel/* Returns selection number of selected group row that contains the specified value in the given group column. Returns NULL if the value is not found. */(p_rg_id in RECORDGROUP,p_gc_id in GROUPCOLUMN,p_value in VARCHAR2)RETURN NUMBER ISv_grpsel_count NUMBER;v_grprow_no NUMBER;
BEGIN--Only loop through the selected group rows.v_grpsel_count := GET_GROUP_SELECTION_COUNT(p_rg_id);FOR v_grpsel_no IN 1 .. v_grpsel_count LOOP--Get row number of selected row.v_grprow_no := GET_GROUP_SELECTION(p_rg_id,v_grpsel_no);IF GET_GROUP_CHAR_CELL(p_gc_id,v_grprow_no) = p_value THENRETURN(v_grpsel_no);
END IF;END LOOP;RETURN(null);
END;
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......................................................................................................................................................Lesson 10: Working with Record Groups
Technical NoteIf a global record group is created from (or populated with) a query while executing a Form A, and the query string contains bind variable references that are local to A (:block.item or :PARAMETER.param), then when Form A terminates execution, the global query record group is converted to a global nonquery record group. The record group retains its data, but a subsequent POPULATE_GROUP is considered an error.
Instructor NoteDemonstration: Use Orders2.fmb to demonstrate the use of a global record group. Click the Product_Lov button to display a list of values form. Using [Ctrl] + click, select the products that you want. Then click the OK button. The products selected are returned by way of a global record group to the ORDERS form. You can show the When-Mouse-Click trigger of the lov_product form.
Copyright Oracle Corporation, 2001. All rights reserved.®
Defining Global Record Groups
• Record group visible to all forms inan application
• “Scope” parameter
– FORM_SCOPE (default)
– GLOBAL_SCOPE
...CREATE_GROUP(group_name, scope);
...CREATE_GROUP_FROM_QUERY(group_name,
query, scope);
...CREATE_GROUP(group_name, scope);
...CREATE_GROUP_FROM_QUERY(group_name,
query, scope);
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......................................................................................................................................................Defining Global Record Groups
Defining Global Record GroupsA global record group allows creation at run time of record groups that are visible to all forms in an application.
Scope ParameterA “scope” parameter can be added to the CREATE_GROUP and CREATE_GROUP_FROM_QUERY built-ins. The value for this scope can be either:
• FORM_SCOPE
• GLOBAL_SCOPE
If you omit this parameter, the default is FORM_SCOPE.
Once created, a global record group persists for the remainder of the application.
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......................................................................................................................................................Lesson 10: Working with Record Groups
Copyright Oracle Corporation, 2001. All rights reserved.®
Manipulating List ItemsProgrammatically
• ADD_LIST_ELEMENT
• DELETE_LIST_ELEMENT
• CLEAR_LIST
• GET_LIST_ELEMENT_LABEL
• GET_LIST_ELEMENT_VALUE
• GET_LIST_ELEMENT_COUNT
• POPULATE_LIST
• RETRIEVE_LIST
Copyright Oracle Corporation, 2001. All rights reserved.®
POPULATE_LIST RETRIEVE_LIST
CHAR Column 1
Using a Record Groupwith a List Item
Labels Values
CHAR Column 2
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......................................................................................................................................................Manipulating List Items Programmatically
Manipulating List Items ProgrammaticallyWhen you define a list item at design time, you specify the possible labels and values on the Properties window. However, you can also manipulate list items programmatically at run time by using built-in functions. Some of these functions require the use of record groups.
Using a Record Group with a List ItemYou can transfer information between a list item and a record group by using the POPULATE_LIST and RETRIEVE_LIST built-in functions. The record group that is used as the second parameter for these functions must satisfy these requirements:
• The record group must contain exactly two group columns of type CHAR.
• The first group column must store the list element label.
• The second group column must store the list element value.
Built-in Function DescriptionADD_LIST_ELEMENT Adds a list element (label and value) at the speci-
fied position (index) to the given list itemCLEAR_LIST Clears all list elements from the given list item
(After clearing, the list item contains only the null element.)
DELETE_LIST_ELEMENT Deletes the list element at the specified position (index) from the given list item
GET_LIST_ELEMENT_COUNT Returns the number (in CHAR format) of list ele-ments in the given list item, including list elements with NULL values
GET_LIST_ELEMENT_LABEL Returns the label of the list element at the specified position (index) in the given list item
GET_LIST_ELEMENT_VALUE Returns the value of the list element at the speci-fied position (index) in the given list item
POPULATE_LIST Clears the given list item and populates the list item with the values from the specified record group
RETRIEVE_LIST Retrieves the list elements (labels and values) from the given list item and stores them in the specified record group
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......................................................................................................................................................Lesson 10: Working with Record Groups
Instructor NoteDemonstration: Use rec_grp.fmb to demonstrate the code of the POPULATE_LIST_WITH_QUERY procedure.
Explain that the When-Create-Record trigger is used here because it is too late to use the When-List-Changed trigger.
Another option is to use the When-Mouse-Down trigger.
Copyright Oracle Corporation, 2001. All rights reserved.®
Implementing Dynamic List Items
Find record group
Yes ID NULL? No
Create group from query
Populate group
Yes Success? No
Populate list
Display first list label
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......................................................................................................................................................Implementing Dynamic List Items
Implementing Dynamic List ItemsThe procedure and trigger below illustrate how you can populate a list itemprogrammatically at run time using a given SELECT statement.
Note: The retrieved rows are transferred to the list item by way of a record group.
PROCEDURE populate_list_with_query--Populates the given list item with the specified query.(p_list_item in VARCHAR2,p_query in VARCHAR2)IS/* Name the record group after the list item (no
block prefix). */cst_rg_name constant VARCHAR2(30) :=
GET_ITEM_PROPERTY(p_list_item,item_name);v_rg_id RECORDGROUP;
BEGINv_rg_id := FIND_GROUP(cst_rg_name);IF ID_NULL(v_rg_id) THENv_rg_id := CREATE_GROUP_FROM_QUERY(cst_rg_name,p_query);
END IF;IF POPULATE_GROUP(v_rg_id) = 0 THEN
POPULATE_LIST(p_list_item,v_rg_id);/* Force display of first list element label
in the list item. */COPY(GET_LIST_ELEMENT_VALUE(p_list_item,1),p_list_item);
END IF;END populate_list_with_query;
When-Create-Record on the ORD BlockBEGIN
POPULATE_LIST_WITH_QUERY(’ord.customer_id’,’SELECT name, to_char(id) FROM s_customer ORDER BY name’);
END;
Note: In this example, the customer name is the (visible) list label and the customer ID is the (actual) list value.
Technical Note Because a base table list item must specify a value for either the Initial property or the Mapping of Other Values property, the record group used to dynamically populate a list item must also contain this value. Be sure the record group query returns this value. For more information, see Note 1010798.6, available on MetaLink: http://www.metalink.oracle.com.
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......................................................................................................................................................Lesson 10: Working with Record Groups
Instructor NoteDemonstration: Use rec_grp.fmb to demonstrate the code of the ADD_COMBO_BOX_ELEMENT procedure.
Copyright Oracle Corporation, 2001. All rights reserved.®
Adding Values to Combo Boxes
Get number of list elements
For alllistelements
Element value=Item value?
Yes No
Return
Add list element with item value
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......................................................................................................................................................Adding Values to Combo Boxes
Adding Values to Combo BoxesFor a combo box, you can choose an existing value from the list, but also type in a new value. The procedure and trigger below show how a new value can be automatically added to the list of existing values of a combo box.
Note: The added list elements are lost when you exit from the form.PROCEDURE add_combo_box_element/* Adds a new list element at the end of the given combo-box list
if it is not already present in the combo-box list. */(p_list_item in VARCHAR2)IS
v_listel_count NUMBER;BEGIN
/* First check if current list-item value is already present in list. */
v_listel_count := GET_LIST_ELEMENT_COUNT(p_list_item);FOR v_listel_idx IN 1 .. v_listel_count LOOP
IF GET_LIST_ELEMENT_VALUE(p_list_item, v_listel_idx)= UPPER(NAME_IN(p_list_item)) THENRETURN;
END IF;END LOOP;/* Current list-item value not found in list;
add new list element at end of list. */ADD_LIST_ELEMENT(p_list_item, v_listel_count + 1,
INITCAP(NAME_IN(p_list_item)),UPPER(NAME_IN(p_list_item)));END;
When-Validate-Item on the ORD.PAYMENT_TYPE Item (Combo Box)BEGIN
ADD_COMBO_BOX_ELEMENT(:SYSTEM.TRIGGER_ITEM);END;
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......................................................................................................................................................Lesson 10: Working with Record Groups
Copyright Oracle Corporation, 2001. All rights reserved.®
Summary
In this lesson, you should have learned how to:• Define design-time query and static
record groups
• Define run time query and nonqueryrecord groups
• Use Built-in functions for populatingrecord groups
• Define Global record groups
Copyright Oracle Corporation, 2001. All rights reserved.®
Summary
• Use record groups for:
– Constructing dynamic SELECT statements
– Storing or passing data
– Populating or storing list items
• Manipulate list items programmatically
– Built-in functions for list items
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......................................................................................................................................................Summary
SummaryA record group is an internal Forms data structure that is similar to a database table.
Three Record Group Types• Query record group
• Non query record group
• Static record group
Defining Record Groups at Design Time• Creating query and static record groups
• Modifying SELECT statements and column definitions of record groups
Built-ins for Controlling Record Groups• Creating and deleting record groups
• Modifying the structure of record groups
• Populating record groups
• Getting record group cell values
• Processing record group rows
• Finding record group objects
Defining a Global Record Group• Created at run time only
• Visible to all forms in an application
• Scope parameter
Uses for Record Groups• Constructing dynamic SELECT statements
• Storing form configuration information
• Communicating within a form
• Passing data to other Oracle products
• Populating or storing list items
Manipulating List Items Programmatically Built-in for list items
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......................................................................................................................................................Lesson 10: Working with Record Groups
Copyright Oracle Corporation, 2001. All rights reserved.®
Practice 10 Overview
This practice covers the following topics:
• Basing a dynamically populated list itemon a design-time query record group
• Basing a dynamically populated list itemon a run-time query record group
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......................................................................................................................................................Practice Overview: Lesson 10
Practice Overview: Lesson 10This practice guides you through the creation of design-time and run-time query record groups.
Practice Contents• Convert a text item into a list item that is populated dynamically at run
time by a design-time query record group.
• Create a list item that is populated dynamically at run time by a run-time query record group.
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......................................................................................................................................................Lesson 10: Working with Record Groups
Practice 10 1 Create a dynamic list item populated from a design-time query record
group. The record group will hold region ID and the name of the departments in the S_DEPT table.
a Open the Employees form. Save as EmpXX where XX is your student course number. In the Object Navigator, create a record group named DEPT_ID based on the query below:SELECT name || ‘ in region ’ || TO_CHAR(region_id) Name, TO_CHAR(id) Id
FROM s_dept
UNION
SELECT ‘none’ Name, ‘0’ Id from dual
ORDER BY 1
b Convert the text item DEPT_ID into a list item, with a Poplist style. Resize the list item in the Layout Editor.
c Create one element in the list item. Specify a label of ‘Dummy’ and a value of ‘0’. Set the Mapping of Other Values property to ‘0’.
d Create a procedure called POPULATE_DEPT_LIST. This procedure will accept the list item name as an argument and populate the list item dynamically at run time, using the design-time query record group. You can import the code from the pr10_1.txt file.
e Call the procedure each time a new record is created.
f Save and compile your form module to test.
If you have time2 Replace the design-time query record group in the Employee form with
a run-time query-based record group.
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......................................................................................................................................................Practice 10
a Delete the DEPT_ID record group and remove the code from the When-Create-Record trigger.
b Create a procedure called CREATE_DEPT_LIST which will dynamically create a record group called QDEPT, if it does not already exist. The procedure will also populate the record group by using the query: SELECT name ||TO_CHAR(region_id) Name,
TO_CHAR(id) Id
FROM s_dept
UNION
SELECT ‘none’ Name, to_char(0) Id
FROM dual
ORDER BY 1
c The procedure will also populate the list item S_EMP.DEPT_ID.
d You can import the procedure code from pr10_2.txt file.
e Call the procedure from the When-Create-Record trigger.
f Save and compile your form module to test.
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......................................................................................................................................................Lesson 10: Working with Record Groups