Android：surfaceview的模板写法

public class MySurfaceView extends SurfaceView implements SurfaceHolder.Callback,Runnable{
    private SurfaceHolder mHolder;//SurfaceHolder
    private Canvas mCanvas;//用于绘制的Canvas
    private boolean mIsDrawing;//子线程标志位

    public MySurfaceView(Context context) {
        super(context);
        init();
    }

    public MySurfaceView(Context context, AttributeSet attrs) {
        super(context, attrs);
        init();
    }

    public MySurfaceView(Context context, AttributeSet attrs, int defStyleAttr) {
        super(context, attrs, defStyleAttr);
        init();
    }

    private void init(){
        mHolder=getHolder();
        mHolder.addCallback(this);
        setFocusable(true);
        setFocusableInTouchMode(true);
        setKeepScreenOn(true);

    }


    //创建
    @Override
    public void surfaceCreated(SurfaceHolder holder) {
        mIsDrawing=true;
        new Thread(this).start();

    }

    //改变
    @Override
    public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) {

    }

    //销毁
    @Override
    public void surfaceDestroyed(SurfaceHolder holder) {
        mIsDrawing=false;
    }

    @Override
    public void run() {
        while(mIsDrawing){
            draw();
        }
    }

    private void draw(){
        try{
            mCanvas=mHolder.lockCanvas();
            //这里写要绘制的内容
        }catch (Exception e){

        }finally {
            if(mCanvas!=null){
                mHolder.unlockCanvasAndPost(mCanvas);//提交画布内容
            }
        }
    }
}