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CanvasWatchFaceService.Engine

public class CanvasWatchFaceService.Engine
extends WatchFaceService.Engine

java.lang.Object
   ↳ android.service.wallpaper.WallpaperService.Engine
     ↳ android.support.wearable.watchface.WatchFaceService.Engine
       ↳ android.support.wearable.watchface.CanvasWatchFaceService.Engine


The actual implementation of a watch face that draws on a Canvas. You must implement onCreateEngine() to return your concrete Engine implementation.

Summary

Public constructors

CanvasWatchFaceService.Engine()

Public methods

void invalidate()

Schedules a call to onDraw(Canvas, Rect) to draw the next frame.

void onDestroy()
void onDraw(Canvas canvas, Rect bounds)

Draws the watch face.

void onSurfaceChanged(SurfaceHolder holder, int format, int width, int height)
void onSurfaceCreated(SurfaceHolder holder)
void onSurfaceRedrawNeeded(SurfaceHolder holder)
void postInvalidate()

Posts a message to schedule a call to onDraw(Canvas, Rect) to draw the next frame.

Inherited methods

From class android.support.wearable.watchface.WatchFaceService.Engine
From class android.service.wallpaper.WallpaperService.Engine
From class java.lang.Object

Public constructors

CanvasWatchFaceService.Engine

CanvasWatchFaceService.Engine ()

Public methods

invalidate

void invalidate ()

Schedules a call to onDraw(Canvas, Rect) to draw the next frame. Must be called on the main thread.

onDestroy

void onDestroy ()

onDraw

void onDraw (Canvas canvas, 
                Rect bounds)

Draws the watch face.

Parameters
canvas Canvas: the canvas to draw into

bounds Rect: the bounds in which the watch face should be drawn

onSurfaceChanged

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

Parameters
holder SurfaceHolder

format int

width int

height int

onSurfaceCreated

void onSurfaceCreated (SurfaceHolder holder)

Parameters
holder SurfaceHolder

onSurfaceRedrawNeeded

void onSurfaceRedrawNeeded (SurfaceHolder holder)

Parameters
holder SurfaceHolder

postInvalidate

void postInvalidate ()

Posts a message to schedule a call to onDraw(Canvas, Rect) to draw the next frame. Unlike invalidate(), this method is thread-safe and may be called on any thread.