title: TimerTask can not update UI?
body: <pre><code> new Timer().schedule(new TimerTask() {
  
          public void run() {
              KeyBoardUtil.showKeyBoard(et_search);
          }
      }, 300);
  </code></pre>
  
  <p>I show the keyboard use TimerTask,and it runs fine.
  how to explain it?</p>