title: QGraphicsObject auto destruction
body: <p><code>QGraphicsObject</code> inherit from both <code>QGraphicsItem</code> and <code>QObject</code>, but unlike most of QObject subclasses the constructor of QGraphicsObject doesn't have a <code>QObject *parent</code> parameter.</p>
  
  <p>so does that mean that I should provide such a parameter in the constructor when I subclass it or even use <code>setParent</code> method to have the auto-destruction feature ?</p>
  
  <p>PS: I have Qt 5</p>