title: How to disable button while AlphaAnimation running
body: <p>I want to disable click on button when the animation running.
  the code is below:</p>
  
  <pre><code>    AlphaAnimation anim = new AlphaAnimation(0.0f, 1.0f);
      anim.setDuration(4000);
      anim.setRepeatMode(Animation.REVERSE);
      btnTag.startAnimation(anim);
  </code></pre>
  
  <p>So i want to cant click the button until animation done.</p>