title: QML: Get QObject parent
body: <p>QML introduces a separate ownership (<code>QObject</code>) tree from the visual tree (QtQuick scene graph).</p>
  
  <ul>
  <li><code>parent</code> returns the visual parent.</li>
  <li><code>children</code> returns the visual children.</li>
  <li><code>data</code> returns the <code>QObject</code> children.</li>
  </ul>
  
  <p>But how do I access the <code>QObject</code> parent?</p>
  
  <p>FYI, I intend on dynamically creating and destroying nested layouts containing a custom type, so I need to manage the <code>QObject</code> tree - just using the visual tree will result in the 'wrong' objects disappearing after reparenting and then deleting.</p>