[Qt-interest] WheelEvent propagation

[Oliver Demetz]

Hi,

My MainWidget contains several buttons (with menus) and a subclass of 
QGraphicsView, call it MainView.

I have some functionality associated with the mouse wheel, which has to 
be performed fron the MainWidget class. It shall only be executed if the 
mouse is over the Main View.

Therefore I implemeted:

class MainWidget : public QWidget{
//...
     protected: void wheelEvent ( QWheelEvent * event )
     {
         if (m_view.underMouse())
         {
             //do the funcitonality
         }
     }
}

and the view ignores wheel events:

class MainView: public QGraphicsView{
//...
     protected: void wheelEvent ( QWheelEvent * event )
     {
         event->ignore();
     }
}

Thsi works perfectly, BUT:

As I said there are QPushButtons in my MainWidget with a menu.

If this menu is open, and if I click into the view in order to close the 
menu, then the wheel funcitonality is not executed.

I was able to track this down, that the wheel event handler of the 
MainView gets the event, but not the wheelevent handler of the MainWidget.

How can thsi be?
It is just if the menu of a button was open and if I click directly on 
the view then.

If I click somehere else in my MainWidget, move the cursor over the view 
and roll the wheel then,everything works fine.

Thanks in advance
Olli