title: Override checkable QGroupBox toggle behaviour
body: <p>I've subclassed the QGroupBox class, with the checkable property enabled. I'm trying to override the behaviour of the toggle/checked events.</p>
  
  <p>Here's the code:</p>
  
  <pre><code>class SideWidgetGroupBox: public QGroupBox
  {
      Q_OBJECT
  public:
      SideWidgetGroupBox(QWidget* parent = 0): QGroupBox(parent)
      {
          this-&gt;setCheckable(true);
          connect(this, SIGNAL(toggled(bool)), this, SLOT(my_toggled(bool)));
      }
  
  private slots:
      void my_toggled (bool on)
      {
          std::cout &lt;&lt; "my toggled method" &lt;&lt;std::endl;
      }
  };
  </code></pre>
  
  <p>So far so good, my slot gets executed. However the groupboxs' contents also get enabled/disabled. Is there a way to prevent that? Or do I have to manually reset the original enabled/disabled state?</p>