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

Canvas的实际执行情况。您必须实现onCreateEngine()才能返回具体的Engine实现。

Summary

Public constructors
`CanvasWatchFaceService.Engine()`

Public methods
`void`	`invalidate()` 计划拨打 `onDraw(Canvas, Rect)`以绘制下一帧。
`void`	`onDestroy()`
`void`	`onDraw(Canvas canvas, Rect bounds)` 绘制表盘。
`void`	`onSurfaceChanged(SurfaceHolder holder, int format, int width, int height)`
`void`	`onSurfaceCreated(SurfaceHolder holder)`
`void`	`onSurfaceRedrawNeeded(SurfaceHolder holder)`
`void`	`postInvalidate()` 发布消息以安排致电 `onDraw(Canvas, Rect)`来绘制下一帧。

From class android.support.wearable.watchface.WatchFaceService.Engine

`final int`	`getInterruptionFilter()` 返回用户选择的中断过滤器。
`final int`	`getNotificationCount()` 返回流中通知卡的总数。
`final Rect`	`getPeekCardPosition()` 返回第一张偷看卡的位置。
`final int`	`getUnreadCount()` 返回流中未读通知卡的数量。
`final boolean`	`isInAmbientMode()` 返回表盘是否处于环境模式。
`void`	`onAmbientModeChanged(boolean inAmbientMode)` 当设备进入或退出环境模式时调用。
`Bundle`	`onCommand(String action, int x, int y, int z, Bundle extras, boolean resultRequested)`
`void`	`onCreate(SurfaceHolder holder)`
`void`	`onDestroy()`
`void`	`onInterruptionFilterChanged(int interruptionFilter)` 当用户更改中断过滤器时调用。
`void`	`onNotificationCountChanged(int count)` 当流中通知卡的总数已更改时调用。
`void`	`onPeekCardPositionUpdate(Rect rect)` 当第一张偷看卡位于屏幕上时调用。
`void`	`onPropertiesChanged(Bundle properties)` 当确定设备的属性时调用。
`void`	`onTapCommand(int tapType, int x, int y, long eventTime)` 当轻触或触摸相关事件发生时调用。
`void`	`onTimeTick()` 定期调用以更新表盘显示的时间。
`void`	`onUnreadCountChanged(int count)` 当流中未读通知卡的数量发生变化时调用。
`void`	`onVisibilityChanged(boolean visible)` 打电话通知您表盘变得可见或隐藏。
`void`	`setWatchFaceStyle(WatchFaceStyle watchFaceStyle)` 设置手表脸型。

From class android.service.wallpaper.WallpaperService.Engine

`void`	`dump(String arg0, FileDescriptor arg1, PrintWriter arg2, String[] arg3)`
`int`	`getDesiredMinimumHeight()`
`int`	`getDesiredMinimumWidth()`
`SurfaceHolder`	`getSurfaceHolder()`
`boolean`	`isPreview()`
`boolean`	`isVisible()`
`void`	`onApplyWindowInsets(WindowInsets arg0)`
`Bundle`	`onCommand(String arg0, int arg1, int arg2, int arg3, Bundle arg4, boolean arg5)`
`void`	`onCreate(SurfaceHolder arg0)`
`void`	`onDesiredSizeChanged(int arg0, int arg1)`
`void`	`onDestroy()`
`void`	`onOffsetsChanged(float arg0, float arg1, float arg2, float arg3, int arg4, int arg5)`
`void`	`onSurfaceChanged(SurfaceHolder arg0, int arg1, int arg2, int arg3)`
`void`	`onSurfaceCreated(SurfaceHolder arg0)`
`void`	`onSurfaceDestroyed(SurfaceHolder arg0)`
`void`	`onSurfaceRedrawNeeded(SurfaceHolder arg0)`
`void`	`onTouchEvent(MotionEvent arg0)`
`void`	`onVisibilityChanged(boolean arg0)`
`void`	`setFixedSizeAllowed(boolean arg0)`
`void`	`setOffsetNotificationsEnabled(boolean arg0)`
`void`	`setTouchEventsEnabled(boolean arg0)`

From class java.lang.Object

CanvasWatchFaceService.Engine ()

void invalidate ()

安排电话onDraw(Canvas, Rect)绘制下一帧。必须在主线程中调用。

void onDestroy ()

void onDraw (Canvas canvas,
                Rect bounds)

绘制表盘。

Parameters
`canvas`	`Canvas`: the canvas to draw into
`bounds`	`Rect`: the bounds in which the watch face should be drawn

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

void onSurfaceCreated (SurfaceHolder holder)

Parameters
`holder`	`SurfaceHolder`

void onSurfaceRedrawNeeded (SurfaceHolder holder)

Parameters
`holder`	`SurfaceHolder`

void postInvalidate ()

发布消息安排电话onDraw(Canvas, Rect)绘制下一帧。与invalidate()不同，此方法是线程安全的，可以在任何线程上调用。