两处mHandler.postDelayed()有什么不同。

Question

public class MainActivity extends AppCompatActivity {

private TextView  mTextView;
private ImageView mImageView;

private Handler mHandler = new Handler();

private int images[] = {R.drawable.chun, R.drawable.dong, R.drawable.qiu, R.drawable.xia};
private int index;

//    private MyRunnable mMyRunnable = new MyRunnable();

class MyRunnable implements Runnable {

    @Override
    public void run() {
        index++;
        index = index % 4;
        mImageView.setImageResource(images[index]);

       1. mHandler.postDelayed(new MyRunnable(), 2000);
    }
}

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    mTextView = (TextView) findViewById(R.id.textview);
    mImageView = (ImageView) findViewById(R.id.imageView);

   2. mHandler.postDelayed(new MyRunnable(), 2000);
}

}
在代码中已标记了两处代码的位置，有哪位能解答下，这两处相同代码的含义有什么不同？？

Answer 1

第一句写在runnable里面会隔两秒调一次
第二句只在两秒后调用一次