Re: Where'd my gtk+-1.2 mouse events go ?

[Olexiy Avramchenko <olexiy irtech cn ua>]

Nix wrote:

> Hi ! I have a drawing area inside a viewport inside a scrollwindow.  I
> have set the followings on the drawing area:
>
>  gtk_widget_set_events (GTK_WIDGET (drawing_area), GDK_EXPOSURE_MASK
>                        | GDK_LEAVE_NOTIFY_MASK
>                        | GDK_BUTTON_PRESS_MASK
>                        | GDK_BUTTON_RELEASE_MASK
>                        | GDK_KEY_PRESS_MASK
>                        | GDK_POINTER_MOTION_MASK
>                        | GDK_POINTER_MOTION_HINT_MASK);
>
> This should give me unfettered access to all mouse and mouse motion
> events.  That is, if I were to add a printf to the motion_notify
> handler, when I move the mouse, it should dowse the terminal in printf
> messages, right ?  Well, not in my case, for some reason.
>
> I have printfs for button_press_event, motion_notify_event, and
> button_release_event.  When the mouse enters the drawing area, it
> generates exactly 1 (!) motion event.  If I depress the mouse button, it
> generates 1 button_press_event (unsurprisingly).  If I then drag the
> mouse, it once again generates exactly 1 motion event.  Why only 1 ? 
> This seems to work well enough on other windows.
>
> Does the scrollwindow, or the viewport my drawing area is embedded in
> absorb the motion and mouse button events ?
Because of GDK_POINTER_MOTION_HINT_MASK. This is the special case, you 
should ask for events with gdk_window_get_pointer() with this mask set...

Olexiy