Android使用TransitionDrawable渐变切换多张图片

使用TransitionDrawable渐变切换多张图片，供大家参考，具体内容如下

1、定义变量

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

2、填充图片

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]);
     }
   }
 }

3、定义hander

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;
   }
 });

4、开启线程发送消息，让transition一直在改变

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();
       }
     }
   }
 }

5、在onCreate()中开启线程，改变transition,切换图片

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

6、在onDestroy()中结束线程

mThreadFlag = false;//结束线程

来源：https://blog.csdn.net/sinat_25112321/article/details/79141481