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Classes
- WallpaperService
- WallpaperService.Engine

Added in API level 7

public abstract class

WallpaperService

extends Service

java.lang.Object
↳	android.content.Context
	↳	android.content.ContextWrapper
		↳	android.app.Service
			↳	android.service.wallpaper.WallpaperService

Class Overview

A wallpaper service is responsible for showing a live wallpaper behind applications that would like to sit on top of it. This service object itself does very little -- its only purpose is to generate instances of WallpaperService.Engine as needed. Implementing a wallpaper thus involves subclassing from this, subclassing an Engine implementation, and implementing onCreateEngine() to return a new instance of your engine.

Summary

Nested Classes
class	WallpaperService.Engine	The actual implementation of a wallpaper.

Constants
String	SERVICE_INTERFACE	The `Intent` that must be declared as handled by the service.
String	SERVICE_META_DATA	Name under which a WallpaperService component publishes information about itself.

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Inherited Constants

From class android.app.Service

From class android.content.Context

From interface android.content.ComponentCallbacks2

int	TRIM_MEMORY_BACKGROUND	Level for `onTrimMemory(int)` : the process has gone on to the LRU list.
int	TRIM_MEMORY_COMPLETE	Level for `onTrimMemory(int)` : the process is nearing the end of the background LRU list, and if more memory isn't found soon it will be killed.
int	TRIM_MEMORY_MODERATE	Level for `onTrimMemory(int)` : the process is around the middle of the background LRU list; freeing memory can help the system keep other processes running later in the list for better overall performance.
int	TRIM_MEMORY_RUNNING_CRITICAL	Level for `onTrimMemory(int)` : the process is not an expendable background process, but the device is running extremely low on memory and is about to not be able to keep any background processes running.
int	TRIM_MEMORY_RUNNING_LOW	Level for `onTrimMemory(int)` : the process is not an expendable background process, but the device is running low on memory.
int	TRIM_MEMORY_RUNNING_MODERATE	Level for `onTrimMemory(int)` : the process is not an expendable background process, but the device is running moderately low on memory.
int	TRIM_MEMORY_UI_HIDDEN	Level for `onTrimMemory(int)` : the process had been showing a user interface, and is no longer doing so.

Public Constructors
	WallpaperService ()

Public Methods
final IBinder	onBind ( Intent intent) Implement to return the implementation of the internal accessibility service interface.
void	onCreate () Called by the system when the service is first created.
abstract WallpaperService.Engine	onCreateEngine () Must be implemented to return a new instance of the wallpaper's engine.
void	onDestroy () Called by the system to notify a Service that it is no longer used and is being removed.

Protected Methods
void	dump ( FileDescriptor fd, PrintWriter out, String[] args) Print the Service's state into the given stream.

[Expand]

Inherited Methods

From class android.app.Service

void	dump ( FileDescriptor fd, PrintWriter writer, String[] args) Print the Service's state into the given stream.
final Application	getApplication () Return the application that owns this service.
abstract IBinder	onBind ( Intent intent) Return the communication channel to the service.
void	onConfigurationChanged ( Configuration newConfig) Called by the system when the device configuration changes while your component is running.
void	onCreate () Called by the system when the service is first created.
void	onDestroy () Called by the system to notify a Service that it is no longer used and is being removed.
void	onLowMemory () This is called when the overall system is running low on memory, and actively running processes should trim their memory usage.
void	onRebind ( Intent intent) Called when new clients have connected to the service, after it had previously been notified that all had disconnected in its `onUnbind(Intent)` .
void	onStart ( Intent intent, int startId) This method was deprecated in API level 5. Implement `onStartCommand(Intent, int, int)` instead.
int	onStartCommand ( Intent intent, int flags, int startId) Called by the system every time a client explicitly starts the service by calling `startService(Intent)` , providing the arguments it supplied and a unique integer token representing the start request.
void	onTaskRemoved ( Intent rootIntent) This is called if the service is currently running and the user has removed a task that comes from the service's application.
void	onTrimMemory (int level) Called when the operating system has determined that it is a good time for a process to trim unneeded memory from its process.
boolean	onUnbind ( Intent intent) Called when all clients have disconnected from a particular interface published by the service.
final void	startForeground (int id, Notification notification) Make this service run in the foreground, supplying the ongoing notification to be shown to the user while in this state.
final void	stopForeground (boolean removeNotification) Remove this service from foreground state, allowing it to be killed if more memory is needed.
final void	stopSelf () Stop the service, if it was previously started.
final void	stopSelf (int startId) Old version of `stopSelfResult(int)` that doesn't return a result.
final boolean	stopSelfResult (int startId) Stop the service if the most recent time it was started was `startId` .

From class android.content.ContextWrapper

From class android.content.Context

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.

From interface android.content.ComponentCallbacks

From interface android.content.ComponentCallbacks2

Constants

public static final String SERVICE_INTERFACE

Added in API level 7

The Intent that must be declared as handled by the service. To be supported, the service must also require the BIND_WALLPAPER permission so that other applications can not abuse it.

Constant Value: "android.service.wallpaper.WallpaperService"

public static final String SERVICE_META_DATA

Added in API level 7

Name under which a WallpaperService component publishes information about itself. This meta-data must reference an XML resource containing a < wallpaper > tag.

Constant Value: "android.service.wallpaper"

Public Constructors

public WallpaperService ()

Added in API level 7

Public Methods

public final IBinder onBind ( Intent intent)

Added in API level 7

Implement to return the implementation of the internal accessibility service interface. Subclasses should not override.

Parameters

intent	The Intent that was used to bind to this service, as given to `Context.bindService` . Note that any extras that were included with the Intent at that point will not be seen here.

Returns

Return an IBinder through which clients can call on to the service.

public void onCreate ()

Added in API level 7

Called by the system when the service is first created. Do not call this method directly.

public abstract WallpaperService.Engine onCreateEngine ()

Added in API level 7

Must be implemented to return a new instance of the wallpaper's engine. Note that multiple instances may be active at the same time, such as when the wallpaper is currently set as the active wallpaper and the user is in the wallpaper picker viewing a preview of it as well.

public void onDestroy ()

Added in API level 7

Called by the system to notify a Service that it is no longer used and is being removed. The service should clean up any resources it holds (threads, registered receivers, etc) at this point. Upon return, there will be no more calls in to this Service object and it is effectively dead. Do not call this method directly.

Protected Methods

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

Added in API level 7

Print the Service's state into the given stream. This gets invoked if you run "adb shell dumpsys activity service <yourservicename>" (note that for this command to work, the service must be running, and you must specify a fully-qualified service name). This is distinct from "dumpsys <servicename>", which only works for named system services and which invokes the dump(FileDescriptor, String[]) method on the IBinder interface registered with ServiceManager.

Parameters

fd	The raw file descriptor that the dump is being sent to.
out	The PrintWriter to which you should dump your state. This will be closed for you after you return.
args	additional arguments to the dump request.

Results

Classes

WallpaperService

Class Overview

Summary

Constants

public static final String SERVICE_INTERFACE

public static final String SERVICE_META_DATA

Public Constructors

public WallpaperService ()

Public Methods

public final IBinder onBind ( Intent intent)

Parameters

Returns

public void onCreate ()

public abstract WallpaperService.Engine onCreateEngine ()

public void onDestroy ()

Protected Methods

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

Parameters