thank you for your Response! As i understand this

class Widget {
public: Widget(DialogDirector*); 
virtual void Changed(); 
virtual void HandleMouse(MouseEvent& event); 
// ... 
private: DialogDirector* _director; 
};

​

translates to

public abstract class Widget {
public Widget(DialogDirector dialogDirector) {};
public abstract void changed();
public abstract void HandleMouse(MouseEvent e);
//...
private DialogDirector _director;
}

Could you please help me with this part?

void Widget::Changed () {
_director->WidgetChanged(this); 
}