Android Final Report2

8/6/2019 Android Final Report2

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Department of Computer Science Android OS

VISVESRAYA TECHNOLOGICAL UNIVERSITY

BELGAUM-590018.

TECHNICAL SEMINAR REPORT

ON

“ANDROID OPERATING SYSTEM”BACHELOR DEGREE

IN

COMPUTER SCIENCE ENGINEERING.

Presented By

CHANDAN.V.T 1MVO7CS020

GURUSHANKAR.C.N 1MV07CS031

HARISH.M 1MV07CS034

Department of Computer Science

SIR M. VISVESVARAYA INSTITUTE OF TECHNOLOGY

Krishnadevarayanagar, Hunasamaranahalli, Via Yelahanka,

Bangalore-562157

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Contents:

1.Abstract2.Introduction

3.Android Architecture

4.User Features for Android 3.0

5.Limitation

6.Conclusion

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Abstract:

Android is a software stack for

devices that includes an operating system, middleware and key applications. Android is a software

platform and operating system for mobile devices based on the Linux operating system and developed by Google and the Open Handset Alliance. It allows developers to write managed code in a Java-likelanguage that utilizes Google-developed Java libraries, but does not support programs developed innative code.

The unveiling of the Android platform on 5 November 2007 was announced with thefounding of the Open Handset Alliance, a consortium of 34 hardware, software and telecomcompanies devoted to advancing open standards for mobile devices. When released in 2008, most of the Android platform will be made available under the Apache free-software and open-sourcelicense .

Introduction:

What is Android?

Android is a software platform and operating system for mobile devices, based on the Linuxkernel and developed by Google and later the Open Handset Alliance. It allows developers to writemanaged code in the Java language, controlling the device via Google-developed Java libraries.Applications written in C and other languages can be compiled to ARM native code and run, but thisdevelopment path is not officially supported by Google.

The unveiling of the Android platform on 5 November 2007 was announced with the founding of the

Open Handset Alliance, a consortium of 48 hardware, software, and telecom companies devoted toadvancing open standards for mobile devices. Google released most of the Android code under theApache license, a free-software and open source license.

What is The Open Handset Alliance?

Open Handset Alliance, is a consortium of several companies which include Google, HTC,Intel, Motorola, Qualcomm, T-Mobile, Sprint Nextel and NVIDIA... These companies which aim todevelop technologies that will significantly lower the cost of developing and distributing mobiledevices and services. The Android platform is the first step in this direction -- a fully integratedmobile "software stack" that consists of an operating system, middleware, user-friendly interface andapplications.

License

Android is under version 2 of the Apache Software License (ASL).The Apache license allowsmanufacturers and mobile operators to innovate using the platform without the requirement tocontribute those innovations back to the open source community.

ANDROID ARCHITECTURE

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Exploring in detail:The Linux kernel:

Android Architecture is based on Linux 2.6 kernel . It helps to manage security, memorymanagement, process management, network stack and other important issues. The kernel provides anabstraction layer between the hardware and the rest of the software stack. It includes manyenhancements and modifications. Drivers are programs that control hardware devices. For example,the Nexus One has a camera. The Android kernel includes a camera driver, which allows the user tosend commands to the camera hardware. rivers are programs that control hardware devices. For example, the Nexus One has a camera. The Android kernel includes a camera driver, which allows theuser to send commands to the camera hardware. Therefore, the user should bring Linux in his mobiledevice as the main operating system and install all the drivers required in order to run it. Android

provides the support for the Qualcomm MSM7K chipset family. For instance, the current kernel treesupports Qualcomm MSM 7200A chipsets, but in the second half of 2008 we should see mobiledevices with stable version Qualcomm MSM 7200, which includes of features:

• Bluetooth 1.2 and Wi-Fi support

• CDMA and GPRS network support

• Digital audio support for mp3 and other formats

• Support for Linux and other third-party operating systems

• Java hardware acceleration and support for Java applications

• Camera up to 6.0 megapixels

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• and lots of other.

The Libraries:

In the next level we can see a set of native Libraries written in C/C++, which are responsiblefor stable performance of various components. You can think of libraries as a set of instructions that

tell the device how to handle different kinds of data. For example, the media framework librarysupports playback and recording of various audio, video and picture formats. Other libraries include athree-dimensional acceleration library (for devices with accelerometers) and a Web browser library.Surface Manager is responsible for composing different drawing surfaces on the mobile screen. Itmanages the access for different processes to compose 2D and 3D graphic layers. OpenGL ES andSGL make a core of graphic libraries and are used accordingly for 3D and 2D hardware acceleration.Moreover, it is possible to use 2D and 3D graphics in the same application in Android. The mediaframework was provided by Packet Video, one of the members of OHA. It gives libraries for a

playback and recording support for all the major media and static image files. FreeType libraries areused to render all the bitmap and vector fonts. For data storage, Android uses SQLite. As I mentioned

before, it is extra light rational management system, which locates a single file for all operationsrelated to database. WebKit, the same browser used by Apples’ Safari, was modified by Android inorder to fit better in a small size screens.

The Android Runtime:

At the same level there is Android Runtime , where the main component Dalvik VirtualMachine is located. Android runtime layer includes a set of core Java libraries -- Android application

programmers build their apps using the Java programming language. The Dalvik Virtual Machine isdeveloped by Dan Bornstein, and named after the Dalvik village in Iceland

Three main design targets:

• It runs on a limited CPU and RAM (250-500MHz) (20-40 MB).

• It runs atop an OS with no swap space.

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• It runs on a device with limited power.

Dalvik replaces the JVM in providing the runtime environment to Java platform applications. TheVM runs Java applications which have been converted to the Dalvik Executable format .dex. The dxtool available in the SDK converts Java bytcode to DVM bytcode at build time. The dx format is a

highly efficient and compact bytecode. dx files can be installed on different devices and can be further modified after being installed to increase efficiency.

A virtual machine is a software application that behaves as if it were an independent device with itsown operating system. You can run a virtual machine on a computer that operates on a completelydifferent OS than the physical machine's OS. The Android OS uses virtual machines to run eachapplication as its own process. That's important for a few reasons. First, no application is dependentupon another. Second, if an application crashes, it shouldn't affect any other applications running onthe device. Third, it simplifies memory management. It was designed specifically for Android runningin limited environment, where the limited battery, CPU, memory and data storage are the main issues.Android gives an integrated tool “dx”, which converts generated byte code from .jar to .dex file, after this byte code becomes much more efficient to run on the small processors. As the result, it is possibleto have multiple instances of Dalvik virtual machine running on the single device at the same time.

The Application Framework:

After that, we have Application Framework , written in Java language. This includes the programs that manage the phone's basic functions like resource allocation, telephone applications,switching between processes or programs and keeping track of the phone's physical location.Application developers have full access to Android's application framework. This allows them to takeadvantage of Android's processing capabilities and support features when building an Androidapplication. It is a toolkit that all applications use, ones which come with mobile device like Contactsor SMS box, or applications written by Google and any Android developer. It has several componentswhich I will discuss. The Activity Manager manages the life circle of the applications and provides acommon navigation backstack for applications, which are running in different processes. The Package

Manager keeps track of the applications, which are installed in the device. The Windows Manager isJava programming language abstraction on the top of lower level services that are provided by theSurface Manager. The Telephony Manager contains of a set of API necessary for calling applications.Content Providers was built for Android to share a data with other applications, for instance, thecontacts of people in the address book can be used in other applications too. The Resource Manager isused to store localized strings, bitmaps, layout file descriptions and other external parts of theapplication. The View System generates a set of buttons and lists used in UI. Other components like

Notification manager is used to customize display alerts and other functions.

At the top of Android Architecture we have all the Applications , which are used by the final user. Byinstalling different applications, the user can turn his mobile phone into the unique, optimized andsmart mobile phone. This is where you find the basic functions of the device such as making phonecalls, accessing the Web browser and accessing your contacts list. If you're an average user, this is the

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layer you'll use most. You do that with the user interface. Only Google programmers, applicationdevelopers and hardware manufacturers access the other layers further down the stack.

User Features for Android 3.0 (Honeycomb):

New UI designed from the ground up for tablets

Android 3.0 is a new version of the Android platform that is specifically optimized for devices with larger screen sizes, particularly tablets. It introduces a brand new, truly virtual and“holographic” UI design, as well as an elegant, content-focused interaction model .

Android 3.0 builds on the things people love most about Android — refined multitasking, richnotifications, Home screen customization, widgets, and more — and transforms them with a vibrant,3D experience and deeper interactivity, making them familiar but even better than before.

System Bar, for global status and notifications

Across the system and in all applications, users have quick access to notifications, systemstatus, and soft navigation buttons in a System Bar, available at the bottom of the screen. The SystemBar is always present and is a key touchpoint for users, but in a new "lights out mode" can also bedimmed for full-screen viewing, such as for videos.

Action Bar, for application control

In every application, users have access to contextual options, navigation, widgets, or other types of content in an Action Bar, displayed at the top of the screen. The Action Bar is always presentwhen an application is in use, although its content, theme, and other properties are managed by theapplication rather than the system. The Action Bar is another key touchpoint for users, especially withaction items and an overflow dropdown menu, which users frequently access in a similar manner inmost applications.

Recent Apps, for easy visual multitasking

Multitasking is a key strength of Android and it is central to the Android 3.0 experience. Asusers launch applications to handle various tasks, they can use the Recent Apps list in the System Bar to see the tasks underway and quickly jump from one application context to another. To help usersrapidly identify the task associated with each app, the list shows a snapshot of its actual state when theuser last viewed it.

Redesigned keyboard

The Android soft keyboard is redesigned to make entering text fast and accurate on larger screen sizes. The keys are reshaped and repositioned for improved targeting, and new keys have beenadded, such as a Tab key, to provide richer and more efficient text input. Users can touch-hold keys toaccess menus of special characters and switch text/voice input modes from a button in the SystemBar.

Improved text selection, copy and paste

When entering or viewing text, a new UI lets users quickly select a word by press-hold andthen adjust the selection area as needed by dragging a set of bounding arrows to new positions. Userscan then select an action from the Action Bar, such as copy to the clipboard, share, paste, web search,or find.

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New connectivity options

Android 3.0 includes new connectivity features that add versatility and convenience for users.Built-in support for Media/Picture Transfer Protocol lets users instantly sync media files with a USB-connected camera or desktop computer, without needing to mount a USB mass-storage device. Users

can also connect full keyboards over either USB or Bluetooth, for a familiar text-input environment.For improved wi-fi connectivity, a new combo scan reduces scan times across bands and filters. Newsupport for Bluetooth tethering means that more types of devices can share the network connection of an Android-powered device.

Updated set of standard apps

The Android 3.0 platform includes an updated set of standard applications that are designed for use onlarger screen devices. The sections below highlight some of the new features.

Browser

The browser includes new features that let users navigate and organize more efficiently.Multiple tabs replace browser windows and a new “incognito” mode allows anonymous browsing.Bookmarks and history are presented and managed in a single unified view. Users can now choose toautomatically sign into Google sites on the browser with a supplied account and sync bookmarks withGoogle Chrome. New multitouch support is now available to JavaScript and plugins. Users can enjoya better browsing experience at non-mobile sites through an improved zoom and viewport model,overflow scrolling, support for fixed positioning, and more.

Camera and Gallery

The Camera application has been redesigned to take advantage of a larger screen for quick access to exposure, focus, flash, zoom, front-facing camera, and more. To let users capture scenes innew ways, it adds built-in support for time-lapse video recording. The Gallery application lets usersview albums and other collections in full-screen mode, with easy access to thumbnails for other

photos in the collection.

Contacts

The Contacts app uses a new two-pane UI and Fast Scroll to let users easily organize andlocate contacts. The application offers improved formatting of international phone numbers as user types, based on home country and an international number parsing library. Contact information is

presented in a card-like UI, making it easier for users to read and edit contacts.

Email

The Email application uses a new two-pane UI to make viewing and organizing messagesmore efficient. The app lets users select one or more messages, then select an action from the ActionBar, such as moving them to a folder. Users can sync attachments for later viewing and keep track of email using a home screen Widget.

Developer Features for Android 3.0 (Honeycomb):

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The Android 3.0 platform is designed specially to meet the unique needs of applications ondevices with larger screen sizes. It offers all of the tools developers need to create incredible visualand interaction experiences on these devices.

• New UI framework for creating great tablet apps•

High-performance 2D and 3D graphics• Support for multicore processor architectures• Rich multimedia and connectivity• Enhancements for enterprise• Compatibility with existing apps

New UI Framework for creating great tablet apps

Redesigned UI widgets

Android 3.0 offers an updated set of UI widgets that developers can use to quickly add newtypes of content to their applications. The new UI widgets are redesigned for use on larger screenssuch as tablets and incorporate the new holographic UI theme. Several new widget types are available,including a 3D stack, search box, a date/time picker, number picker, calendar, popup menu, andothers. Most of the redesigned UI widgets can now be used as remote views in application widgetsdisplayed on the home screen. Applications written for earlier versions can inherit the new Widgetdesigns and themes.

Persistent Action Bar

The platform provides each application with its own instance of the Action Bar at the top of the screen, which the application can use to give the user quick access to contextual options, widgets,status, navigation, and more. The application can also customize the display theme of its Action Bar

instance. The Action Bar lets developers expose more features of their applications to users in afamiliar location, while also unifying the experience of using an application that spans multipleActivities or states.

Richer notifications

Notifications are a key part of the Android user experience because they let applications showkey updates and status information to users in real time. Android 3.0 extends this capability, lettingdevelopers include richer content and control more properties. A new builder class lets developersquickly create notifications that include large and small icons, a title, a priority flag, and any

properties already available in previous versions. Notifications can offer more types of content by building on the expanded set of UI Widgets that are now available as remote Views.

Multiselect, clipboard, and drag-and-drop

The platform offers convenient new interaction modes that developers can use. For managingcollections of items in lists or grids, developers can offer a new multiselect mode that lets userschoose multiple items for an action. Developers can also use a new system-wide Clipboard to let userseasily copy any type of data into and out of their applications. To make it easier for users to manageand organize files, developers can now add drag-and-drop interaction through a DragEventframework.

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http://developer.android.com/sdk/android-3.0-highlights.html#ui

http://developer.android.com/sdk/android-3.0-highlights.html#graphics

http://developer.android.com/sdk/android-3.0-highlights.html#multicore

http://developer.android.com/sdk/android-3.0-highlights.html#multimedia

http://developer.android.com/sdk/android-3.0-highlights.html#enterprise

http://developer.android.com/sdk/android-3.0-highlights.html#compatibility

http://developer.android.com/sdk/android-3.0-highlights.html#ui

http://developer.android.com/sdk/android-3.0-highlights.html#graphics

http://developer.android.com/sdk/android-3.0-highlights.html#multicore

http://developer.android.com/sdk/android-3.0-highlights.html#multimedia

http://developer.android.com/sdk/android-3.0-highlights.html#enterprise

http://developer.android.com/sdk/android-3.0-highlights.html#compatibility




High-performance 2D and 3D graphics

New animation framework

The platform includes a flexible new animation framework that lets developers easily animatethe properties of UI elements such as Views, Widgets, Fragments, Drawables, or any arbitrary object.Animations can create fades or movement between states, loop an animated image or an existinganimation, change colors, and much more. Adding animation to UI elements can add visual interest toan application and refine the user experience, to keep users engaged.

Hardware-accelerated 2D graphics

Android 3.0 offers a new hardware-accelerated OpenGL renderer that gives a performance boost to many common graphics operations for applications running in the Android framework. Whenthe renderer is enabled, most operations in Canvas, Paint, Xfermode, ColorFilter, Shader, and Cameraare accelerated. Developers can control how hardware-acceleration is applied at every level, fromenabling it globally in an application to enabling it in specific Activities and Views inside theapplication.

Renderscript 3D graphics engine

Renderscript is a runtime 3D framework that provides both an API for building 3D scenes aswell as a special, platform-independent shader language for maximum performance. UsingRenderscript, you can accelerate graphics operations and data processing. Renderscript is an ideal wayto create high-performance 3D effects for applications, wallpapers, carousels, and more.

Support for multicore processor architectures

Android 3.0 is the first version of the platform designed to run on either single or multicore processor architectures. A variety of changes in the Dalvik VM, Bionic library, and elsewhere addsupport for symmetric multiprocessing in multicore environments. These optimizations can benefit allapplications, even those that are single-threaded. For example, with two active cores, a single-threaded application might still see a performance boost if the Dalvik garbage collector runs on thesecond core. The system will arrange for this automatically.

Pluggable DRM framework

Android 3.0 includes an extensible DRM framework that lets applications manage protectedcontent according to a variety of DRM mechanisms that may be available on the device. For application developers, the framework API offers an consistent, unified API that simplifies themanagement of protected content, regardless of the underlying DRM engines.

Digital media file transfer

The platform includes built-in support for Media/Picture Transfer Protocol (MTP/PTP) over USB, which lets users easily transfer any type of media files between devices and to a host computer.Developers can build on this support, creating applications that let users create or manage media filesthat they may want to transfer or share across devices.

More types of connectivity

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The platform offers new connectivity that developers can build on. API support for BluetoothA2DP and HSP profiles lets applications query Bluetooth profiles for connected devices, audio state,and more, then notify the user. For example, a music application can check connectivity and statusand let the user know that music is playing through a stereo headset. Applications can also register toreceive system broadcasts of pre-defined vendor-specific AT commands, such as Platronics Xevent.For example, an application could receive broadcasts that indicate a connected device's battery leveland could notify the user or take other action as needed. Applications can also take advantage of the

platform's new support for full keyboards connected by USB or Bluetooth.

Limitations:

The android 3.0 is a tablet-only release of Android.

The main difference between the iOS web experience and that of android 3.0 operating systems is thelack of support for Flash. However, Flash isn't ready for Android 3.0 yet, although it is expected to bequite soon. Android 3.0 supports HTML5 though, so you will have no problem with content.

Android has passed the 200,000 app marker where as iOS wins outright in terms of numbers andquality of apps – there are over 400,000 available.

If Android 3.0 brings a 720p resolution for the display, you won't be able to switch to that resolution because the displays won't support it. There might be other features as well that won't be supported byany of the current phones, but that's normal.

Google Talk functions and only the simplest implementation of Bluetooth. It'll work with

Bluetooth headsets but that's about it; no Bluetooth stereo, no contacts exchange, no modem pairing and no using wireless keyboards.Android uses a non-standard jvm: there is no guarantee that the same software will run onmultiple devices

Firefox Mobile isn't coming to Android because of Android LimitationsFennec won't play nice with Android Market because apps in Android Market need to be

programmed with a custom form of Java to run on Android. Mozilla and the Fennec peeps won'thave that and won't be releasing any form of Firefox until Google amends the limitation of Android Apps.

Conclusion:We can only hope that the next versions of Android have overcome the actual limitations and that thefuture possibilities became a reality.

Bibliography:

•An Introduction to Android. Jason Chen, 2008

–http://www.android.com/

•Introduction to Android Development. Frank Ableson, May 12, 2009 – http://www.ibm.com/developerworks/opensource/library/os-android-devel/index.html?S_TACT=105AGX52&S_CMP=content

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•Homepage of OHA– http://www.openhandsetalliance.com/

•Introduction to Android Development. Ed Burnette, 2009

•http://developer.android.com –Home page for Android development and documentation

•http://groups.google.com/group/android-beginners –Forum for development questions (beginner)

•http://groups.google.com/group/android-developers –Forum for development questions (advanced)

•http://www.planetandroid.com –Blogs and news from around the Android community

•http://pragprog.com/titles/eband –<book> Hello, Android: Introducing Google’s Mobile DevelopmentPlatform

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