title: Using UIPopoverBackgroundView class
body: <p>Apple is missing documentation on how to use <code>UIPopoverBackgroundView</code> class introduced in iOS5. Anyone have an example?</p>
  
  <p>I have tried to subclass it, but my XCode 4.2 on Lion is missing <code>UIPopoverBackgroundView.h</code></p>
  
  <p><strong><em>Edit:</em></strong> Unsurprisingly, it should have been imported as <code>#import &lt;UIKit/UIPopoverBackgroundView.h&gt;</code></p>