Engine
open class Engine
| kotlin.Any | |
| ↳ | android.service.wallpaper.WallpaperService.Engine |
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 WallpaperService#onCreateEngine() to return your concrete Engine implementation.
Summary
| Public constructors | |
|---|---|
Engine()Default constructor |
|
| Public methods | |
|---|---|
| open Int |
Convenience for |
| open Int |
Convenience for |
| open Context? |
The |
| open SurfaceHolder! |
Provides access to the surface in which this wallpaper is drawn. |
| open Int |
Returns the current wallpaper flags indicating which screen this Engine is rendering to. |
| open Boolean |
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. |
| open Boolean |
Return whether the wallpaper is currently visible to the user, this is the last value supplied to |
| open Unit |
Notifies the engine that wallpaper colors changed significantly. |
| open Unit |
onApplyWindowInsets(insets: WindowInsets!)Called with the current insets that are in effect for the wallpaper. |
| open Bundle! |
Process a command that was sent to the wallpaper with |
| open WallpaperColors? |
Called by the system when it needs to know what colors the wallpaper is using. |
| open Unit |
onCreate(surfaceHolder: SurfaceHolder!)Called once to initialize the engine. |
| open Unit |
onDesiredSizeChanged(desiredWidth: Int, desiredHeight: Int)Called when an application has changed the desired virtual size of the wallpaper. |
| open Unit |
Called right before the engine is going away. |
| open Unit |
onOffsetsChanged(xOffset: Float, yOffset: Float, xOffsetStep: Float, yOffsetStep: Float, xPixelOffset: Int, yPixelOffset: Int)Called to inform you of the wallpaper's offsets changing within its contain, corresponding to the container's call to |
| open Unit |
onSurfaceChanged(holder: SurfaceHolder!, format: Int, width: Int, height: Int)Convenience for |
| open Unit |
onSurfaceCreated(holder: SurfaceHolder!)Convenience for |
| open Unit |
onSurfaceDestroyed(holder: SurfaceHolder!)Convenience for |
| open Unit |
onSurfaceRedrawNeeded(holder: SurfaceHolder!)Convenience for |
| open Unit |
onTouchEvent(event: MotionEvent!)Called as the user performs touch-screen interaction with the window that is currently showing this wallpaper. |
| open Unit |
onVisibilityChanged(visible: Boolean)Called to inform you of the wallpaper becoming visible or hidden. |
| open Unit |
onWallpaperFlagsChanged(which: Int)Called when the current wallpaper flags change. |
| open Unit |
onZoomChanged(zoom: Float)Called when the zoom level of the wallpaper changed. |
| open Unit |
setOffsetNotificationsEnabled(enabled: Boolean)Control whether this wallpaper will receive notifications when the wallpaper has been scrolled. |
| open Unit |
setTouchEventsEnabled(enabled: Boolean)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 | |
|---|---|
| open Unit |
dump(prefix: String!, fd: FileDescriptor!, out: PrintWriter!, args: Array<String!>!) |
Public constructors
Public methods
getDesiredMinimumHeight
open fun getDesiredMinimumHeight(): Int
Convenience for WallpaperManager.getDesiredMinimumHeight(), returning the height that the system would like this wallpaper to run in.
getDesiredMinimumWidth
open fun getDesiredMinimumWidth(): Int
Convenience for WallpaperManager.getDesiredMinimumWidth(), returning the width that the system would like this wallpaper to run in.
getDisplayContext
open fun getDisplayContext(): Context?
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.
| Return | |
|---|---|
Context? |
A Context for current display. |
getSurfaceHolder
open fun getSurfaceHolder(): SurfaceHolder!
Provides access to the surface in which this wallpaper is drawn.
getWallpaperFlags
open fun getWallpaperFlags(): Int
Returns the current wallpaper flags indicating which screen this Engine is rendering to.
| Return | |
|---|---|
Int |
Value is either 0 or a combination of android.app.WallpaperManager#FLAG_SYSTEM, and android.app.WallpaperManager#FLAG_LOCK |
isPreview
open fun isPreview(): Boolean
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
open fun isVisible(): Boolean
Return whether the wallpaper is currently visible to the user, this is the last value supplied to onVisibilityChanged(boolean).
notifyColorsChanged
open fun notifyColorsChanged(): Unit
Notifies the engine that wallpaper colors changed significantly. This will trigger a onComputeColors() call.
onApplyWindowInsets
open fun onApplyWindowInsets(insets: WindowInsets!): Unit
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.
| Parameters | |
|---|---|
insets |
WindowInsets!: Insets to apply. |
onCommand
open fun onCommand(
action: String!,
x: Int,
y: Int,
z: Int,
extras: Bundle!,
resultRequested: Boolean
): Bundle!
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.
| Parameters | |
|---|---|
action |
String!: The name of the command to perform. This tells you what to do and how to interpret the rest of the arguments. |
x |
Int: Generic integer parameter. |
y |
Int: Generic integer parameter. |
z |
Int: Generic integer parameter. |
extras |
Bundle!: Any additional parameters. |
resultRequested |
Boolean: If true, the caller is requesting that a result, appropriate for the command, be returned back. |
| Return | |
|---|---|
Bundle! |
If returning a result, create a Bundle and place the result data in to it. Otherwise return null. |
onComputeColors
open fun onComputeColors(): WallpaperColors?
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 android.app.WallpaperColors object is by using android.app.WallpaperColors#fromBitmap(Bitmap) or android.app.WallpaperColors#fromDrawable(Drawable), but you can also specify your main colors by constructing a android.app.WallpaperColors object manually.
This method must be called from the main thread of your app.
| Return | |
|---|---|
WallpaperColors? |
Wallpaper colors. |
onCreate
open fun onCreate(surfaceHolder: SurfaceHolder!): Unit
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
open fun onDesiredSizeChanged(
desiredWidth: Int,
desiredHeight: Int
): Unit
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
open fun onDestroy(): Unit
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
open fun onOffsetsChanged(
xOffset: Float,
yOffset: Float,
xOffsetStep: Float,
yOffsetStep: Float,
xPixelOffset: Int,
yPixelOffset: Int
): Unit
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
open fun onSurfaceChanged(
holder: SurfaceHolder!,
format: Int,
width: Int,
height: Int
): Unit
Convenience for SurfaceHolder.Callback.surfaceChanged().
This method must be called from the main thread of your app.
onSurfaceCreated
open fun onSurfaceCreated(holder: SurfaceHolder!): Unit
Convenience for SurfaceHolder.Callback.surfaceCreated().
This method must be called from the main thread of your app.
onSurfaceDestroyed
open fun onSurfaceDestroyed(holder: SurfaceHolder!): Unit
Convenience for SurfaceHolder.Callback.surfaceDestroyed().
This method must be called from the main thread of your app.
onSurfaceRedrawNeeded
open fun onSurfaceRedrawNeeded(holder: SurfaceHolder!): Unit
Convenience for SurfaceHolder.Callback.surfaceRedrawNeeded().
This method must be called from the main thread of your app.
onTouchEvent
open fun onTouchEvent(event: MotionEvent!): Unit
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
open fun onVisibilityChanged(visible: Boolean): Unit
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
open fun onWallpaperFlagsChanged(which: Int): Unit
Called when the current wallpaper flags change.
This method must be called from the main thread of your app.
| Parameters | |
|---|---|
which |
Int: The new flag value Value is either 0 or a combination of android.app.WallpaperManager#FLAG_SYSTEM, and android.app.WallpaperManager#FLAG_LOCK |
See Also
onZoomChanged
open fun onZoomChanged(zoom: Float): Unit
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.
| Parameters | |
|---|---|
zoom |
Float: the zoom level, between 0 indicating fully zoomed in and 1 indicating fully zoomed out. Value is between 0f and 1f inclusive |
setOffsetNotificationsEnabled
open fun setOffsetNotificationsEnabled(enabled: Boolean): Unit
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 |
Boolean: whether the wallpaper wants to receive offset notifications |
setTouchEventsEnabled
open fun setTouchEventsEnabled(enabled: Boolean): Unit
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).
Protected methods
dump
protected open fun dump(
prefix: String!,
fd: FileDescriptor!,
out: PrintWriter!,
args: Array<String!>!
): Unit