1. boolean android.view.View.post(Runnable action): 是listview 继承 view，同样具有此方法

Causes the Runnable to be added to the message queue.

使用Runnalbe 把这个加入到消息队列里面去

2.postDelayed(Runnable action, long delayMillis)

导致可被添加到消息队列,在指定的时间运行。

Causes the Runnable to be added to the message queue. The runnable will be run on the user interface thread.

Parameters
action The Runnable that will be executed.
Returns
Returns true if the Runnable was successfully placed in to the message queue. Returns false on failure, usually because the looper processing the message queue is exiting.