title: How to implement "Collapsible navigation items" as described in the design guide?
body: <p>The section "Collapsible navigation items" of <a href="https://developer.android.com/design/patterns/navigation-drawer.html#Content" rel="nofollow noreferrer">https://developer.android.com/design/patterns/navigation-drawer.html#Content</a>
  specifies </p>
  
  <blockquote>
    <p>"Collapsible navigation items are split. Use the left side for navigation and the right to collapse and expand items." Along a <a href="http://developer.android.com/design/media/navigation_drawer_collapse.png" rel="nofollow noreferrer">very clear illustration</a>.</p>
  </blockquote>
  
  <p>However it does not seem possible to implement this recommended behaviour...</p>
  
  <p>I cannot find a way to differentiate a click on the indicator to a click on the "left side of the navigation item".
  I guess I could add an image view in the group view and implement the "collapse/expand" logic myself, but I find it odd that the design guide recommends something that goes against how the platform works.</p>
  
  <p>So I guess I am missing something... Is it possible to implement this design pattern using the standard group indicator ?</p>
  
  <p>The <a href="https://stackoverflow.com/questions/18129402/navigation-drawer-collapsible-items">question</a> has already been asked, but there is no answer so far.</p>
  
  <p>Thanks in advance for any clarification</p>