Live wallpapers allow users to set animated, interactive backgrounds on their Android home screen. They are built as services that render on the desktop. Developers need the Android SDK 2.1 or higher to create a live wallpaper service that overrides the onCreateEngine method and handles lifecycle callbacks like onVisibility to optimize for performance and battery usage.

1. Android: Live Wallpapers
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2. What are live wallpapers?
 “Richer, animated, interactive backgrounds”
 Provides another means for the user to interact with
your app on their desktop
 Similar to regular Android service, so the application
becomes the desktop!
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3. What do I need?
 Android SDK > 2.1
 Eclipse
 ADT for Eclipse
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4. Android API Levels
 http://developer.android.com/guide/appendix/
api-levels.html
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5. Setting up the Android manifest
 Service permission of
android.permission.BIND_WALLPAPER
 API Level 7 for > 2.1
<uses-sdk android:minSdkVersion="7" />
 Use feature tag
<uses-feature
android:name="android.software.live_wallpaper" />
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6. Example Android manifest
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7. Wallpaper Service
 Abstract class, implement and override
onCreateEngine()
 http://developer.android.com/reference/android/
service/wallpaper/WallpaperService.html
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8. Life Cycle
 onCreate()
 onDestroy()
 onVisibility()
 onOffsetsChanged()
 onSurface...() created, changed, destroyed
 onTouchEvent()
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9. Gotchas
 Battery life!
 CPU even 1ghz is not infinite
 onVisibility(), when the wallpaper becomes invisible
shut everything down
 Multi touch?
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10. Other options
 Widgets
 Apps
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11. Demo
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