Post on 12-Jul-2015
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Mobile Programming Kalmesh Nyamagoudar 9th August 2013
Why Mobile sites/apps??
§ Users carry the device wherever they go § Better interaction with users § Great monetization benefits
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Issues § Smaller screens § Limited computing power § Limited network connectivity
Smart Phones
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§ iPhone : What I do § Android : What we will talk today…. § Windows 8 : Hidden gem § …. § …. § ….
Installations
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§ JDK : http://jdk7.java.net/ § ADT : http://developer.android.com/sdk/index.html
› Installs both eclipse and android SDK
§ Create AVD : Android Virtual Device
Let’s create an android project
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Decide your App UI
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What each UI element represents in Android
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Text Field Button
Grid Of Images
Go to Eclipse : Things to do
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§ Create all the UI elements(TextField, Button, GridView) › Give ids to all UI elements › Create a variable for each UI element
› Connect each variable with its corresponding UI element
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§ Create a method for Button : OnClick
§ Add Internet permission to Android Manifest
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§ Implement the method that has to execute on click of button
REST Query
• Where to store the results ??? : ArrayList Of ImageResult Objects • Create a separate class : ImageResult with two variables
• thumbUrl • fullUrl
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§ Run your code once on Emulator › Check the output on LogCat’s DEBUG section › URLs of image results are printed
§ How to show these images in GridView? › Create an adapter(A subclass of ArrayAdapter<ImageResult) class › Create an adapter object in main activity › Attach it to gridView
› Populate entries of arraylist into adapter once response is parsed.
§ Run it › URLs instead of images in the Grid View
Adding Images to GridView
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§ Create a new layout (Android XML file) › Add a SmartImageView to the new layout created
§ Change the name of layout in adapter › Dear adapter, please make use of SmartImageView whenever you try to display
something
§ How to load the url into image view?? › Job of adapter
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§ ~~ Launching another screen(activity) › Demo : YahooImageSearch
§ Google Image Search › Demo : GridImageSearch
§ ListView Instead of a GridView?? › Demo : YahooExtendedAnswersClient
§ Oauth?? My Images from Flickr?? › Scribe.jar › https://github.com/thecodepath/android-rest-client-template › Demo : FlickrClient