title: How to add spinner to subtitle - as in the Play Music app for Android?
body: <p><img src="https://i.stack.imgur.com/TZ3fU.png" alt="Play Music screenshot"></p>
  
  <p>Please refer to the attached image. </p>
  
  <p><code>setListNavigationCallbacks(mSpinnerAdapter, mNavigationCallback)</code> adds a spinner pivoted under <em>"My Library"</em>, and I cannot add a sub-list under it. I am unable to find a method which adds a spinner for <em>"ALL MUSIC"</em>, not messing up with the main title of the action bar.</p>
  
  <p>Any help is appreciated !</p>