title: Collapsible controls in MFC (example included)
body: <p>In the WindowsXP Control panel, you can see a nice collapsible panel control on the left:</p>
  
  <p><a href="https://i.stack.imgur.com/d7GQU.gif" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/d7GQU.gif" alt="alt text"></a><br>
  <sub>(source: <a href="http://screenshots.leeindy.com/ControlPanel/category_view.gif" rel="nofollow noreferrer">leeindy.com</a>)</sub>  </p>
  
  <p>These are not just collapsible, but animated too. I wondered if these are any kind of control accessible to a developer, specifically in MFC? Or are they custom/bespoke functionality?</p>