public void btnClick(View v) {
   Button bt = (Button) v;
   if (isStart) {
     gifView.stopGif();
     bt.setText("start");
   } else {
     gifView.startGif();
     bt.setText("stop");
   }
   isStart = !isStart;
 }
  @Override
  protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_gif_engine);

    screenWidth = getWindowManager().getDefaultDisplay().getWidth();
    screenHeight = getWindowManager().getDefaultDisplay().getHeight();

    fl = (FrameLayout) findViewById(R.id.fl);

    gifView = new GifSurfaceView(this, "20140728194855.gif");

    FrameLayout.LayoutParams flp =
        new FrameLayout.LayoutParams(screenWidth, screenHeight, Gravity.CENTER);
    gifView.setLayoutParams(flp);

    fl.addView(gifView);
  }