paintEvent not getting called with QMainWindow

[DiamonDogX]

I have a class that extends QMainWindow and I overrode the paintEvent method, but it never gets called. I have done something similar when extending QWidget and it does call the method. A little confused here... it seems to be declared correctly:

protected:
virtual void paintEvent(QPaintEvent*);
....
....
void MyWindow:: paintEvent(QPaintEvent*)
{
// never gets here
}