Enable parent paintEvent from subclass-ed QWidget

widget.cpp

void myclass::paintEvent(QPaintEvent *pe) {                                                                                                                                        
  QStyleOption o;                                                                                                                                                                  
  o.initFrom(this);                                                                                                                                                                
  QPainter p(this);                                                                                                                                                                
  style()->drawPrimitive(QStyle::PE_Widget, &o, &p, this);                                                                                                                         
};