title: Hide QWidget but keep the empty space, so there is not effect in the layout
body: <p>There is a <code>QVBoxLayout</code> in which many <code>QHBoxLayout</code> were added. Each <code>QHBoxLayout</code> has the same set of widgets, in principle. In fact I'm hiding some of the widgets and this causes the other widgets to get bigger in order to occupy the space. </p>
  
  <p>Is it possible to keep the empty space? Ideally, I would like to have the other widgets in the same position with the same size.</p>