Re: gtk_widget_unparent

["Norman Black" <stonybrk ix netcom com>]

According to the docs, you are not supposed to use gtk_widget_unparent.
You should probably use gtk_container_remove to remove a widget from a
container widget, unless the contain widget has a specific removal API
call. For example the notebook widget has its own API for removing a
page. Things like the packing boxes do not.

Best Regards,
Norman Black
Stony Brook Software

----- Original Message -----
From: "Dr.Peter Rottengatter" <peter rottengatter de>
To: <gtk-app-devel-list gnome org>
Sent: Wednesday, March 20, 2002 1:46 PM
Subject: gtk_widget_unparent


> Seems I haven't understood gtk_widget_unparent properly. Here is what
I did:
> Problem: I create the GUI using Glade, amongst which is a window with
a notebook
> widget. I use it to display a small set of measurement data, a trace
each page.
> It is not previously determined how many traces there will be.
>
> So I create a single instance of the trace page with Glade, and I need
to add
> "clone" pages to the notebook at runtime as needed.
>
> My thought was to use the Glade-created "create_notebook" function to
build a new
> instance of the notebook widget tree, then unlink the trace page
sub-tree und
> relink it into the notebook that is about to be used. After doing
that, that
> additional instance of the notebook tree (now incomplete) won't be
needed
> anymore.
>
> I figured gtk_widget_unparent would do the unlink action, as
gtk_notebook_append_page
> would do the relink. The additional instance of the notebook tree
could be destroyed
> as usual, afterwards, I thought. Somewhere I thought badly wrong. I
did this in a
> loop for every data trace:
>
>         dummy = create_notes();
>         page = lookup_widget (dummy, "nb_trace_vbox");
>         gtk_widget_unparent (page);
>       /*  gtk_widget_destroy (dummy); */
>         gtk_widget_show_all (page);
>
>         sprintf (tab, "#%d", index);
>         gtk_widget_show (label = gtk_label_new (tab));
>         sprintf (tab, "Trace #%d", index);
>         gtk_widget_show (menu = gtk_label_new (tab));
>
>         gtk_notebook_append_page_menu (book, page, label, menu);
>
> So far, it works. But it segfaults as soon as the gtk_widget_destroy
is uncommented.
> I could just leave dummy in place and destroy it when the shown
notebook is destroyed.
> Or is this fundamentally flawed, and I should do this in a different
way ?
> Cheers  Peter
> --
> ---------------------------------------------------------------------
>       Dr. Peter Rottengatter       peter rottengatter de
>                                    http://www.rottengatter.de
> ---------------------------------------------------------------------
> _______________________________________________
> gtk-app-devel-list mailing list
> gtk-app-devel-list gnome org
> http://mail.gnome.org/mailman/listinfo/gtk-app-devel-list