Re: colormap assertion errors

[Rob Benton <rob benton conwaycorp net>]

Murray Cumming wrote:
> On Mon, 2004-11-29 at 21:54 -0600, Rob Benton wrote:
>
> > I've narrowed down the error to one variable, the Gdk::Colormap.  That's 
> > what's failing the assertion with:
> >
> > -ERRORS---------------------------------------------------------
> > (chip:3201): GLib-GObject-CRITICAL **: file gobject.c: line 1579 
> > (g_object_unref): assertion `G_IS_OBJECT (object)' failed
> > (chip:3201): Gdk-CRITICAL **: file gdkcolor-x11.c: line 690 
> > (gdk_colormap_free_colors): assertion `GDK_IS_COLORMAP (colormap)' failed
> > ----------------------------------------------------------------
> >
> > I'm declaring a Gtk::DrawingArea member variable on the stack and a 
> > Glib::RefPtr<Gdk::Colormap> member variable.  Then I'm using this line 
> > inside the class' constructor:
> >
> > -CODE-----------------------------------------------------------
> > _colormap = _drawarea.get_default_colormap();
> > ----------------------------------------------------------------
>
>
> I have discovered a bug in Gtk::Widget::get_default_colormap(). It needs
> a "refreturn" in the .hg file. I'll fix that.
>
> As a workaround for now, you should be able to using
> Gdk::Screen::get_default()->get_default_colormap(). However, you need at
> least gtkmm 2.4.6, because Screen::get_default() used to have the same
> problem.
>
> By the way, Gtk::Widget::get_default_colormap() is a static function, so
> you don't need the _drawarea instance in order to call it.
>  

Cool, thanks.  It works.  It seemed like free_colors() was getting 
called on the destruction of the Gdk::Colormap object.  Should I be 
calling Gdk::Colormap::free_colors() explicitly?  The 2.4 tutorial 
doesn't mention it.