title: Push out/pull in ActionBar when ListView is scrolled
body: <p>The latest Google Newsstand App features an <code>ActionBar</code> and <code>ViewPager</code> tab bar which slowly eases out the top of the screen when the list below it is scrolled down. <strong>Importantly, it eases out at the same speed the list is scrolled</strong>. When the list is scrolled upwards the <code>ActionBar</code> eases back onto the screen, <strong>again at the same speed the list is scrolled</strong>.</p>
  
  <p><em>I am not referring to the <code>ActionBar</code> <code>hide()</code> and <code>show()</code> methods, instead I want to know how to hide and show the ActionBar at the same rate the list below it is scrolled.</em></p>
  
  <p>How is this achieved? All attempts at finding a documented solution have proven unsuccessful so any help would be appreciated.</p>