Android使用TransitionDrawable渐变切换多张图片

private int change = 0;//记录下标
private int[] ids = new int[]{R.drawable.anim_one, R.drawable.anim_two, R.drawable.anim_three};
private Drawable[] drawables;//图片集合
private Thread mThread;//线程
private boolean mThreadFlag = true;//线程结束标志符

private void initDrawableView() {
    //填充图片
    drawables = new Drawable[ids.length];
    for (int i = 0; i < ids.length; i++) {
      if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
        drawables[i] = getDrawable(ids[i]);
      } else {
        drawables[i] = getResources().getDrawable(ids[i]);
      }
    }
  }

private Handler mHandler = new Handler(new Handler.Callback() {
    @Override
    public boolean handleMessage(Message msg) {
      int duration = msg.arg1;
      TransitionDrawable transitionDrawable = new TransitionDrawable(new Drawable[]{drawables[change % ids.length],
          drawables[(change + 1) % ids.length]});
      change++;//改变标识位置
      repeatPlay.setBackground(transitionDrawable);
      transitionDrawable.startTransition(duration);
      return false;
    }
  });

private class MyRunnable implements Runnable {
    @Override
    public void run() {
      //这个while(true)是做死循环
      while (mThreadFlag) {
        int duration = 5000;//改变的间隔
        Message message = mHandler.obtainMessage();
        message.arg1 = duration;
        mHandler.sendMessage(message);
        try {
          Thread.sleep(duration);
          //隔duration秒发送一次
        } catch (InterruptedException e) {
          e.printStackTrace();
        }
      }
    }
  }

mThread = new Thread(new MyRunnable());
mThread.start();

mThreadFlag = false;//结束线程