title: Setting style for only one kind of widget
body: <p>How can I globally change the style of one specific type of widget? I want to make all QGroupBox instances use the &quot;plastique&quot; style because of that nice border:</p>
  <p>On the left, the GTK style (which I don't like); on the right, the style I want.</p>
  <p><a href="https://i.stack.imgur.com/VQgrc.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/VQgrc.png" alt="Plastique style" /></a><br />
  <sub>(source: <a href="http://qt-project.org/doc/qt-4.8/images/gtk-groupbox.png" rel="nofollow noreferrer">qt-project.org</a>)</sub></p>
  <p><a href="https://i.stack.imgur.com/d6kRt.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/d6kRt.png" alt="Plastique style" /></a><br />
  <sub>(source: <a href="http://qt-project.org/doc/qt-4.8/images/plastique-groupbox.png" rel="nofollow noreferrer">qt-project.org</a>)</sub></p>
  <p>I don't want set the style for every instance of QGroupBox in the program, I want to set it globally like in QApplication::setStyle(), but only for QGroupBox. Is there a way?</p>
  <p>Thanks.</p>