title: how to make smooth alpha animation
body: <p>I have a simple alpha Animation applied to a <code>TextView</code>:</p>
  
  <pre><code> &lt;?xml version="1.0" encoding="utf-8"?&gt;
  &lt;set xmlns:android="http://schemas.android.com/apk/res/android"
  android:interpolator="@android:anim/linear_interpolator" &gt;
  
  &lt;alpha
      android:duration="2000"
      android:fromAlpha="1.0"
      android:repeatCount="infinite"
      android:toAlpha="0.1" /&gt;
  </code></pre>
  
  <p></p>
  
  <p>After the animation ends, the alpha value jumps from 0.1 to its default value (1.0) again. How can I achieve that the <code>TextView</code> will fade in and out smoothly?</p>