WallpaperService.Engine

Engine

public Engine ()

Default constructor

getDesiredMinimumHeight

public int getDesiredMinimumHeight ()

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

getDesiredMinimumWidth

public int getDesiredMinimumWidth ()

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

getDisplayContext

public Context getDisplayContext ()

The Context with resources that match the current display the wallpaper is on. For multiple display environment, multiple engines can be created to render on each display, but these displays may have different densities. Use this context to get the corresponding resources for currently display, avoiding the context of the service.

The display context will never be null after Engine.onCreate(SurfaceHolder) has been called.

getSurfaceHolder

public SurfaceHolder getSurfaceHolder ()

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

getWallpaperFlags

public int getWallpaperFlags ()

Returns the current wallpaper flags indicating which screen this Engine is rendering to.

isPreview

public 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.

isVisible

public boolean isVisible ()

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

notifyColorsChanged

public void notifyColorsChanged ()

Notifies the engine that wallpaper colors changed significantly. This will trigger a onComputeColors() call.

onApplyWallpaper

public WallpaperDescription onApplyWallpaper (int which)

Called when the wallpaper preview rendered by this engine is about to be persisted as a selected wallpaper. The returned WallpaperDescription (if any) will be persisted by the system and passed into subsequent calls to WallpaperService.onCreateEngine(WallpaperDescription). This allows the Engine to perform any necessary bookkeeping before a wallpaper being previewed is set on the device, and update the description if necessary.

onApplyWindowInsets

public void onApplyWindowInsets (WindowInsets insets)

Called with the current insets that are in effect for the wallpaper. This gives you the part of the overall wallpaper surface that will generally be visible to the user (ignoring position offsets applied to it).
This method must be called from the main thread of your app.

onCommand

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

Process a command that was sent to the wallpaper with WallpaperManager.sendWallpaperCommand. The default implementation does nothing, and always returns null as the result.
This method must be called from the main thread of your app.

onComputeColors

public WallpaperColors onComputeColors ()

Called by the system when it needs to know what colors the wallpaper is using. You might return null if no color information is available at the moment. In that case you might want to call notifyColorsChanged() when color information becomes available.

The simplest way of creating a WallpaperColors object is by using WallpaperColors.fromBitmap(Bitmap) or WallpaperColors.fromDrawable(Drawable), but you can also specify your main colors by constructing a WallpaperColors object manually.
This method must be called from the main thread of your app.

onCreate

public void onCreate (SurfaceHolder surfaceHolder)

Called once to initialize the engine. After returning, the engine's surface will be created by the framework.
This method must be called from the main thread of your app.

onDesiredSizeChanged

public void onDesiredSizeChanged (int desiredWidth, 
                int desiredHeight)

Called when an application has changed the desired virtual size of the wallpaper.
This method must be called from the main thread of your app.

onDestroy

public void onDestroy ()

Called right before the engine is going away. After this the surface will be destroyed and this Engine object is no longer valid.
This method must be called from the main thread of your app.

onOffsetsChanged

public 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().
This method must be called from the main thread of your app.

onSurfaceChanged

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

Convenience for SurfaceHolder.Callback.surfaceChanged().
This method must be called from the main thread of your app.

onSurfaceCreated

public void onSurfaceCreated (SurfaceHolder holder)

Convenience for SurfaceHolder.Callback.surfaceCreated().
This method must be called from the main thread of your app.

onSurfaceDestroyed

public void onSurfaceDestroyed (SurfaceHolder holder)

Convenience for SurfaceHolder.Callback.surfaceDestroyed().
This method must be called from the main thread of your app.

onSurfaceRedrawNeeded

public void onSurfaceRedrawNeeded (SurfaceHolder holder)

Convenience for SurfaceHolder.Callback.surfaceRedrawNeeded().
This method must be called from the main thread of your app.

onTouchEvent

public void onTouchEvent (MotionEvent event)

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.
This method must be called from the main thread of your app.

onVisibilityChanged

public void onVisibilityChanged (boolean visible)

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..
This method must be called from the main thread of your app.

onWallpaperFlagsChanged

public void onWallpaperFlagsChanged (int which)

Called when the current wallpaper flags change.
This method must be called from the main thread of your app.

onZoomChanged

public void onZoomChanged (float zoom)

Called when the zoom level of the wallpaper changed. This method will be called with the initial zoom level when the surface is created.
This method must be called from the main thread of your app.

setOffsetNotificationsEnabled

public void setOffsetNotificationsEnabled (boolean enabled)

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.

setTouchEventsEnabled

public 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. By default they are turned off. If enabled, the events will be received in onTouchEvent(android.view.MotionEvent).

dump

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