title: How can a QWidget get the "entire" parent?
body: <p>I have instantiated a widgetClass in MainWindow.cpp.  I want to pass in "this" to this widget as more than just (QWidget* parent) but also (MainWindow* parent).  But on the build, the widgetClass is established before the MainWindow and so it errors out. </p>
  
  <p>I want to get to instanceVariables in the MainWindow??</p>
  
  <p>ie:</p>
  
  <pre><code>myWidget(QWidget* parent, MainWindow* parent);
  </code></pre>