Overriding on_motion_notify_event

I'm trying to override the virtual function on_motion_notify_event in a
Gtk::DrawingArea, but the function never seems to be called. I don't get why,
since DrawingArea inherits from Widget.  So, when does a motion notify event ever occur?

Here's a minimal example of what I mean:

#include <iostream>
#include <gtkmm.h>

class Area: public Gtk::DrawingArea
  Area () {}
  //never called?
  virtual bool on_motion_notify_event (GdkEventMotion *event)
    std::cout << event->x << '\t' << event->y << '\n';

int main (int argc, char **argv)
  Gtk::Main test (argc, argv);
  Gtk::Window window (Gtk::WINDOW_TOPLEVEL);
  Area area;
  window.add (area);
  window.show_all ();
  test.run (window);

[Date Prev][Date Next]   [Thread Prev][Thread Next]   [Thread Index] [Date Index] [Author Index]