title: pyqt qt4 How to add a tiny arrow/collapse button to QSplitter
body: <p>You can customize the thickness and background image of the splitter handle</p>
  
  <p><a href="http://qt-project.org/doc/qt-4.8/stylesheet-examples.html#customizing-qsplitter" rel="noreferrer">http://qt-project.org/doc/qt-4.8/stylesheet-examples.html#customizing-qsplitter</a></p>
  
  <p>But is there a way to add a small graphical arrow button so when the user clicks on it, I can call <code>splitter.setSizes([0, 1])</code> to collapse it.</p>
  
  <p><img src="https://i.imgur.com/sH6XXuV.png" alt="collapsebutton"></p>
  
  <p>I could use a vbox layout with a QButton but it takes up too much space and doesn't look as nice.</p>