title: How to display 2 widgets on the same space?
body: <p>I have this main window on which I would like to put 2 widgets on the same space, i.e. when the user clicks a button then one of the widgets should come up front and the other be hidden and then change places when clicking another button.</p>
  
  <p>My Widget are of different types: one is a QGLWidget and the other one is a QGraphicsView.</p>
  
  <p>How could I put these 2 widgets on the same place?</p>