title: How to hide search bar on scroll? (without UITableViewController)
body: <p>I have a simple UIViewController containing a UITableView and I want to hide search bar inside of navigation bar on scrolling UITableView. I found</p>
  
  <pre class="lang-swift prettyprint-override"><code>navigationItem.hidesSearchBarWhenScrolling = true
  </code></pre>
  
  <p>but it does not work. Is there any way to make it work on UIViewController?</p>