绘制界面

private void drawUI() {
//锁定画布
Canvas lockCanvas = holder.lockCanvas();
// 绘制界面
Paint paint=new Paint();
paint.setColor(Color.RED);
// 绘制矩形
lockCanvas.drawRect(0, 0, 100, 100, paint);
// 解锁画布并提交
holder.unlockCanvasAndPost(lockCanvas);

}
//当Surface创建时调用
@Override
public void surfaceCreated(SurfaceHolder holder) {
renderThread=new RenderThread();
flag=true;
renderThread.start();

}

//当Surface销毁时调用
@Override
public void surfaceDestroyed(SurfaceHolder holder) {
flag=false;

}
//当Surface改变时调用
@Override
public void surfaceChanged(SurfaceHolder holder, int format, int width,
int height) {

}