Re: Signals

["Florent.Devin" <Florent Devin lifl fr>]

Filipe Bonjour wrote:

> Hi,
>
> I'm just starting programming with GTK, and I'm having problems with
> events. Specifically, I'm writing a program (using GTK/Gnome built by
> Glade) to visualize data in 2D/3D using a GtkGlArea widget (a subclass
> of GtkDrawingArea).
>
> In short, I have several drawing options, and I want to send the
> GtkGlArea widget an expose event when the user changes any of these
> options. I have tried things like:
>
>   gtk_signal_emit_by_name(glarea, "expose_event");
>   gtk_signal_emit_by_name(glarea, "expose-event");
>
> (which cause a SIGSEGV) and
>
>   gtk_signal_emit(glarea, 32);
>   gtk_signal_emit(glarea, GDK_EXPOSE);
>   gtk_signal_emit(glarea, gtk_signal_lookup("expose_event",
>                                             GTK_TYPE_GL_AREA));
>   gtk_signal_emit(glarea, gtk_signal_lookup("expose-event",
>                                             GTK_TYPE_GL_AREA));
>
> which are at best ignored. So I have a few questions...
>
> 1) Where are the signal numbers and names defined? I couldn't find them
>    anywhere. For gtk_signal_emit I find it hard to believe that we are
>    expected to give an actual number, I thought there would be some
>    defined symbols, such as "#define GTK_SIGNAL_EXPOSE 32" or something.

gtk_signal_emit_by_name (GTK_OBJECT (widget), "expose_event", widget);

which mean that you have to provide all parameter of the function which
is call when the signal is emited.

In my case the prototype is :
gint f (GtkWidget *widget, GdkEventExpose *event, gpointer userdata)

Hope this help


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Florent DEVIN, 33 (0)3 20 43 47 30, Fax (33) (0)3 20 43 65 66 (Fax LIFL)
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