gtk menu button menu

{
    GtkBuilder *builder;
    GError *err;
    GSimpleAction *show_songs;
    GSimpleActionGroup *group;
    GObject *mb_button;
    GtkPopover *popover;
    gchar **actions;

    /* Load .ui file. */
    err = NULL;
    builder = gtk_builder_new ();
    gtk_builder_add_from_file (builder,
                               "$USER/Projects/gw2c/src/builder.ui",
                               &err);

    if (err)
    {
        g_print ("ERROR: menu_button.c|line 16: GError == %s\n",
                 err->message);

        g_error_free (err);
    }

    /* Setup menu for GtkMenuButton. */
    mb_button = gtk_builder_get_object (builder, "menu-button");
    group = g_simple_action_group_new ();
    show_songs = g_simple_action_new_stateful ("show-songs",
                                               NULL,
                                               g_variant_new_boolean (TRUE));

    g_action_map_add_action (G_ACTION_MAP (group), G_ACTION (show_songs));
    gtk_widget_insert_action_group (GTK_WIDGET (mb_button),
                                    "settings",
                                    G_ACTION_GROUP (group));

    g_signal_connect (show_songs,
                      "change-state",
                      G_CALLBACK (show_songs_state_cb),
                      NULL);

    actions = g_action_group_list_actions (gtk_widget_get_action_group (GTK_WIDGET (mb_button),
                                                                        "settings"));
    g_print ("%s\n", actions[0]);
    g_strfreev (actions);
    if (gtk_widget_get_action_group (GTK_WIDGET (mb_button), "settings") == NULL)
    {
        g_print ("No action group for mb_button\n");
    }

    g_object_unref (builder);
}