title: Rotating refresh button
body: <p>I have a refresh button defined in a layout file as follow:</p>
  
  <pre><code>&lt;ImageButton
        android:id="@+id/btn_refresh_assets"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:layout_gravity="center"
        android:onClick="onClick"
        android:src="@drawable/ic_menu_refresh" /&gt;
  </code></pre>
  
  <p>When his button clicked, an <code>AsyncTask</code> is called to load data from a webservice. Now I want to rotate the refresh icon until the load is complete!!!
  there is some guidlines for doing this in actionbar but my button is placed in the middle of a page and not in actionbar. </p>