Button_ release/pressed_event in DrawingArea

[Kees Kling <ckling upcmail nl>]

Hi,

I'm dispkaying an image in a Gtk::DrawingArea and I try to catch some 
mouse events

so I did:

snippet

Gtk::DrawingArea  drawingRegion = manage ( new Gtk::drawingArea());
drawinRegion->set_events(drawingRegion->get_events() |
               Gdk::POINTER_MOTION_MASK | Gdk::SCROLL_MASK | 
Gdk::BUTTON_RELEASE_MASK );
drawingRegion->signal_expose_event().connect(sigc::mem_fun(*this,&imageModule::on_expose_event));
drawingRegion->signal_scroll_event().connect(sigc::mem_fun(*this,&imageModule::on_scroll_event));
drawingRegion->signal_button_release_event().connect(sigc::mem_fun(*this, 
&imageModule::on_button_release_event));

My signal handler is;

bool imageModule::on_button_release_event (GdkEventButton* event) {
   cout<<"releasing in imagemodule"<<endl;
   return false;
}

but this is never called.
You can also see that I also connect expose_event and scroll_event and 
both work.
What am I doing wrong

Thanks
Kees Kling