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Classes
- WallpaperService
- WallpaperService.Engine

Summary: Ctors | Methods | Protected Methods | Inherited Methods | [Expand All]

Added in API level 7

public class

WallpaperService.Engine

extends Object

java.lang.Object
↳	android.service.wallpaper.WallpaperService.Engine

Class Overview

The actual implementation of a wallpaper. A wallpaper service may have multiple instances running (for example as a real wallpaper and as a preview), each of which is represented by its own Engine instance. You must implement onCreateEngine() to return your concrete Engine implementation.

Summary

Public Constructors
	WallpaperService.Engine ()

Public Methods
int	getDesiredMinimumHeight () Convenience for `WallpaperManager.getDesiredMinimumHeight()` , returning the height that the system would like this wallpaper to run in.
int	getDesiredMinimumWidth () Convenience for `WallpaperManager.getDesiredMinimumWidth()` , returning the width that the system would like this wallpaper to run in.
SurfaceHolder	getSurfaceHolder () Provides access to the surface in which this wallpaper is drawn.
boolean	isPreview () Returns true if this engine is running in preview mode -- that is, it is being shown to the user before they select it as the actual wallpaper.
boolean	isVisible () Return whether the wallpaper is currently visible to the user, this is the last value supplied to `onVisibilityChanged(boolean)` .
Bundle	onCommand ( String action, int x, int y, int z, Bundle extras, boolean resultRequested) Process a command that was sent to the wallpaper with `sendWallpaperCommand(IBinder, String, int, int, int, Bundle)` .
void	onCreate ( SurfaceHolder surfaceHolder) Called once to initialize the engine.
void	onDesiredSizeChanged (int desiredWidth, int desiredHeight) Called when an application has changed the desired virtual size of the wallpaper.
void	onDestroy () Called right before the engine is going away.
void	onOffsetsChanged (float xOffset, float yOffset, float xOffsetStep, float yOffsetStep, int xPixelOffset, int yPixelOffset) Called to inform you of the wallpaper's offsets changing within its contain, corresponding to the container's call to `WallpaperManager.setWallpaperOffsets()` .
void	onSurfaceChanged ( SurfaceHolder holder, int format, int width, int height) Convenience for `SurfaceHolder.Callback.surfaceChanged()` .
void	onSurfaceCreated ( SurfaceHolder holder) Convenience for `SurfaceHolder.Callback.surfaceCreated()` .
void	onSurfaceDestroyed ( SurfaceHolder holder) Convenience for `SurfaceHolder.Callback.surfaceDestroyed()` .
void	onSurfaceRedrawNeeded ( SurfaceHolder holder) Convenience for `SurfaceHolder.Callback.surfaceRedrawNeeded()` .
void	onTouchEvent ( MotionEvent event) Called as the user performs touch-screen interaction with the window that is currently showing this wallpaper.
void	onVisibilityChanged (boolean visible) Called to inform you of the wallpaper becoming visible or hidden.
void	setOffsetNotificationsEnabled (boolean enabled) Control whether this wallpaper will receive notifications when the wallpaper has been scrolled.
void	setTouchEventsEnabled (boolean enabled) Control whether this wallpaper will receive raw touch events from the window manager as the user interacts with the window that is currently displaying the wallpaper.

Protected Methods
void	dump ( String prefix, FileDescriptor fd, PrintWriter out, String[] args)

[Expand]

Inherited Methods

From class java.lang.Object

Object	clone () Creates and returns a copy of this `Object` .
boolean	equals ( Object o) Compares this instance with the specified object and indicates if they are equal.
void	finalize () Invoked when the garbage collector has detected that this instance is no longer reachable.
final Class <?>	getClass () Returns the unique instance of `Class` that represents this object's class.
int	hashCode () Returns an integer hash code for this object.
final void	notify () Causes a thread which is waiting on this object's monitor (by means of calling one of the `wait()` methods) to be woken up.
final void	notifyAll () Causes all threads which are waiting on this object's monitor (by means of calling one of the `wait()` methods) to be woken up.
String	toString () Returns a string containing a concise, human-readable description of this object.
final void	wait () Causes the calling thread to wait until another thread calls the `notify()` or `notifyAll()` method of this object.
final void	wait (long millis, int nanos) Causes the calling thread to wait until another thread calls the `notify()` or `notifyAll()` method of this object or until the specified timeout expires.
final void	wait (long millis) Causes the calling thread to wait until another thread calls the `notify()` or `notifyAll()` method of this object or until the specified timeout expires.

Public Constructors

public WallpaperService.Engine ()

Added in API level 7

Public Methods

public int getDesiredMinimumHeight ()

Added in API level 7

Convenience for WallpaperManager.getDesiredMinimumHeight() , returning the height that the system would like this wallpaper to run in.

public int getDesiredMinimumWidth ()

Added in API level 7

Convenience for WallpaperManager.getDesiredMinimumWidth() , returning the width that the system would like this wallpaper to run in.

public SurfaceHolder getSurfaceHolder ()

Added in API level 7

Provides access to the surface in which this wallpaper is drawn.

public boolean isPreview ()

Added in API level 7

Returns true if this engine is running in preview mode -- that is, it is being shown to the user before they select it as the actual wallpaper.

public boolean isVisible ()

Added in API level 7

Return whether the wallpaper is currently visible to the user, this is the last value supplied to onVisibilityChanged(boolean) .

public Bundle onCommand ( String action, int x, int y, int z, Bundle extras, boolean resultRequested)

Added in API level 7

Process a command that was sent to the wallpaper with sendWallpaperCommand(IBinder, String, int, int, int, Bundle) . The default implementation does nothing, and always returns null as the result.

Parameters

action	The name of the command to perform. This tells you what to do and how to interpret the rest of the arguments.
x	Generic integer parameter.
y	Generic integer parameter.
z	Generic integer parameter.
extras	Any additional parameters.
resultRequested	If true, the caller is requesting that a result, appropriate for the command, be returned back.

Returns

If returning a result, create a Bundle and place the result data in to it. Otherwise return null.

public void onCreate ( SurfaceHolder surfaceHolder)

Added in API level 7

Called once to initialize the engine. After returning, the engine's surface will be created by the framework.

public void onDesiredSizeChanged (int desiredWidth, int desiredHeight)

Added in API level 7

Called when an application has changed the desired virtual size of the wallpaper.

public void onDestroy ()

Added in API level 7

Called right before the engine is going away. After this the surface will be destroyed and this Engine object is no longer valid.

public void onOffsetsChanged (float xOffset, float yOffset, float xOffsetStep, float yOffsetStep, int xPixelOffset, int yPixelOffset)

Added in API level 7

Called to inform you of the wallpaper's offsets changing within its contain, corresponding to the container's call to WallpaperManager.setWallpaperOffsets() .

public void onSurfaceChanged ( SurfaceHolder holder, int format, int width, int height)

Added in API level 7

Convenience for SurfaceHolder.Callback.surfaceChanged() .

public void onSurfaceCreated ( SurfaceHolder holder)

Added in API level 7

Convenience for SurfaceHolder.Callback.surfaceCreated() .

public void onSurfaceDestroyed ( SurfaceHolder holder)

Added in API level 7

Convenience for SurfaceHolder.Callback.surfaceDestroyed() .

public void onSurfaceRedrawNeeded ( SurfaceHolder holder)

Added in API level 9

Convenience for SurfaceHolder.Callback.surfaceRedrawNeeded() .

public void onTouchEvent ( MotionEvent event)

Added in API level 7

Called as the user performs touch-screen interaction with the window that is currently showing this wallpaper. Note that the events you receive here are driven by the actual application the user is interacting with, so if it is slow you will get fewer move events.

public void onVisibilityChanged (boolean visible)

Added in API level 7

Called to inform you of the wallpaper becoming visible or hidden. It is very important that a wallpaper only use CPU while it is visible. .

public void setOffsetNotificationsEnabled (boolean enabled)

Added in API level 15

Control whether this wallpaper will receive notifications when the wallpaper has been scrolled. By default, wallpapers will receive notifications, although the default static image wallpapers do not. It is a performance optimization to set this to false.

Parameters

enabled	whether the wallpaper wants to receive offset notifications

public void setTouchEventsEnabled (boolean enabled)

Added in API level 7

Control whether this wallpaper will receive raw touch events from the window manager as the user interacts with the window that is currently displaying the wallpaper. By default they are turned off. If enabled, the events will be received in onTouchEvent(MotionEvent) .

Protected Methods

protected void dump ( String prefix, FileDescriptor fd, PrintWriter out, String[] args)

Added in API level 14

Results

Classes

WallpaperService.Engine

Class Overview

Summary

Public Constructors

public WallpaperService.Engine ()

Public Methods

public int getDesiredMinimumHeight ()

public int getDesiredMinimumWidth ()

public SurfaceHolder getSurfaceHolder ()

public boolean isPreview ()

public boolean isVisible ()

public Bundle onCommand ( String action, int x, int y, int z, Bundle extras, boolean resultRequested)

Parameters

Returns

public void onCreate ( SurfaceHolder surfaceHolder)

public void onDesiredSizeChanged (int desiredWidth, int desiredHeight)

public void onDestroy ()

public void onOffsetsChanged (float xOffset, float yOffset, float xOffsetStep, float yOffsetStep, int xPixelOffset, int yPixelOffset)

public void onSurfaceChanged ( SurfaceHolder holder, int format, int width, int height)

public void onSurfaceCreated ( SurfaceHolder holder)

public void onSurfaceDestroyed ( SurfaceHolder holder)

public void onSurfaceRedrawNeeded ( SurfaceHolder holder)

public void onTouchEvent ( MotionEvent event)

public void onVisibilityChanged (boolean visible)

public void setOffsetNotificationsEnabled (boolean enabled)

Parameters

public void setTouchEventsEnabled (boolean enabled)

Protected Methods

protected void dump ( String prefix, FileDescriptor fd, PrintWriter out, String[] args)