title: How to reset the column span of a widget in a QGridLayout?
body: <p>Is possible to set the column span of a <code>QLineEdit</code> box after it has been added to the layout? I have two <code>QLineEdit</code> boxes in a <code>QGridLayout</code> that are right next to each other horizontally. During the execution of some of my code, one of these boxes gets hidden. I would like to increase the column span where the hidden one was to avoid a weird gap at the end, and reduce it when needed.</p>
  
  <p>I couldn't really find anything in the Qt documentation for this type of change beyond making the adjustment prior to adding the widget to the layout.</p>