Re: [Vala] GTK and Property problems

[Andrew <rugby471 gmail com>]

On 26/06/10 11:37, pHilipp Zabel wrote:
> On Sat, Jun 26, 2010 at 9:36 AM, Andrew <rugby471 gmail com> wrote:
> > HI guys,
> >
> > Perhaps the simplest way to ask this is, could anyone tell me why when
> > the attached file (Genie) is compiled and then run, do I get these error
> > messages?
> >
> > (wasiliana:2710): Gtk-CRITICAL **: gtk_container_add: assertion
> > `GTK_IS_CONTAINER (container)' failed
> > (wasiliana:2710): GLib-GObject-WARNING **: invalid (NULL) pointer instance
> > (wasiliana:2710): GLib-GObject-CRITICAL **: g_signal_connect_object:
> > assertion `G_TYPE_CHECK_INSTANCE (instance)' failed
>
> I accidentally replied off-list, saying this is because the widgets
> are created as local variables which are never assigned to the object
> properties.
> My first idea to fix this was just to assign to the properties directly:
>
> --- main.gs.orig        2010-06-26 12:04:28.061569285 +0200
> +++ main.gs     2010-06-26 12:18:32.577892738 +0200
> @@ -47,13 +47,13 @@
>         this.delete_event.connect(on_mainwindow_delete_event)
>
>         // Toolbar creation
> -        var scrolled_window = new ScrolledWindow(null, null)
> +        scrolled_window = new ScrolledWindow(null, null)
>         var vbox = new VBox(false, 0)
>         var toolbar_hbox = new HBox(true, 0)
> -        var toolbar = new Toolbar()
> +        toolbar = new Toolbar()
>         var back_button = new ToolButton.from_stock("gtk-go-back")
> -        var forward_button = new ToolButton.from_stock("gtk-go-forward")
> -        var location_entry = new Entry()
> +        forward_button = new ToolButton.from_stock("gtk-go-forward")
> +        location_entry = new Entry()
>
>         //Toolbar Packing
>         toolbar.insert(back_button, -1)
>
> But that failed (after compilation with valac 0.8.0), because the
> property assignment didn't increase the refcount on the widgets.
> Is this a bug in the Genie code generator? Is it fixed in current versions?
> For comparison, this is the C output for the scrolled_window setter method:
>
> void main_window_set_scrolled_window (MainWindow* self,
> GtkScrolledWindow* value) {
>        g_return_if_fail (self != NULL);
>        self->priv->_scrolled_window = value;
>        g_object_notify ((GObject *) self, "scrolled-window");
> }
>
> And this is what I would have expected instead (and what I get from
> vala 0.8.0 when compiling from a .vala source instead of from .gs
> source):
>
> void main_window_set_scrolled_window (MainWindow* self,
> GtkScrolledWindow* value) {
>        GtkScrolledWindow* _tmp0_;
>        g_return_if_fail (self != NULL);
>        self->priv->_scrolled_window = (_tmp0_ = _g_object_ref0 (value),
> _g_object_unref0 (self->priv->_scrolled_window), _tmp0_);
>        g_object_notify ((GObject *) self, "scrolled-window");
> }
>
> regards
> Philipp
> _______________________________________________
> vala-list mailing list
> vala-list gnome org
> http://mail.gnome.org/mailman/listinfo/vala-list

Yes, the first example gives the error:
(wasiliana:1880): Gtk-CRITICAL **: gtk_box_pack: assertion
`GTK_IS_WIDGET (child)' failed
(wasiliana:1880): Gtk-CRITICAL **: gtk_container_add: assertion
`GTK_IS_CONTAINER (container)' failed


Could anyone help out here?

-- 
Andrew