Re: GtkAda callback and event

[DrPi <314@drpi.fr>]

Le 09/09/2021 à 08:56, Emmanuel Briot a écrit :
> You could perhaps consider using some of the higher-level event handling functions that
> are generated as part of the binding. For instance, `gtk-widget.ads` has:
> 
> ```
> type Cb_Gtk_Widget_Gdk_Event_Motion_Boolean is not null access function
>       (Self  : access Gtk_Widget_Record'Class;
>        Event : Gdk.Event.Gdk_Event_Motion) return Boolean;
> 
>     type Cb_GObject_Gdk_Event_Motion_Boolean is not null access function
>       (Self  : access Glib.Object.GObject_Record'Class;
>        Event : Gdk.Event.Gdk_Event_Motion) return Boolean;
> 
>     Signal_Motion_Notify_Event : constant Glib.Signal_Name := "motion-notify-event";
>     procedure On_Motion_Notify_Event
>        (Self  : not null access Gtk_Widget_Record;
>         Call  : Cb_Gtk_Widget_Gdk_Event_Motion_Boolean;
>         After : Boolean := False);
>     procedure On_Motion_Notify_Event
>        (Self  : not null access Gtk_Widget_Record;
>         Call  : Cb_GObject_Gdk_Event_Motion_Boolean;
>         Slot  : not null access Glib.Object.GObject_Record'Class;
>         After : Boolean := False);
>   ```
> 
> This ensures the proper list of parameters for the callback, and automatically gets you
> the Event, for instance.
> 
The problem with these functions is that you can't pass a user record to 
the callback.