title: Collapsing/Expanding view coordinated with Sliding RecyclerView
body: <p>I am trying to achieve the following affect (also see image below):</p>
  
  <ul>
  <li>the app opens with a view (map) partially visible and the <code>RecyclerView</code> at a default anchor point (center image)</li>
  <li>user scrolls the <code>RecyclerView</code> up, the map collapses and the list continues scrolling (right image)</li>
  <li>user scrolls the <code>RecyclerView</code> down, the map expands to a maximum point (note the list should not slide completely off screen but to some anchored point) (left image)</li>
  </ul>
  
  <p><a href="https://i.stack.imgur.com/iTFVD.png" rel="noreferrer"><img src="https://i.stack.imgur.com/iTFVD.png" alt="enter image description here"></a></p>