Re: Optionmenuitem and labels

[Patrice St-Gelais <patrice st-gelais oricom ca>]

Alexander Nagel a écrit:
> Hi,
> i build a option menu like in the gtk-docs and it works fine. Now i want to 
> retrieve the label of the selected menuitem.
> my code
> ConfDatei.NewEntry ("Language", gtk_label_get_text 
> (GTK_LABEL(gtk_bin_get_child(GTK_BIN(gtk_menu_get_active 
> (GTK_MENU(General.LanguageSubMenu)))))));
> 
> Theoretically this should work and it should give me the label.
> Compiling runs without any warning.
> But i get this during execution:
> 
> (trollhunter:7444): Gtk-CRITICAL **: file ../../gtk/gtklabel.c: line 1142 
> (gtk_label_get_text): assertion `GTK_IS_LABEL (label)' failed
> Aborted (core dumped)
> 
> Thanks for help
> alex
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> http://mail.gnome.org/mailman/listinfo/gtk-app-devel-list
> 
___________________________________________________________________

Hi,

Sorry for the delay, I haven't read the list often recently.

It seems that nobody answered. If you haven't found yet, here is how I 
do the thing in a callback, connected to each menu item (it's with GTK 
1.2.x,I don't know if it works with 2.x):

/**************************************************/
void omenu_callb(GtkWidget *wdg, gpointer data) {
	//	Set the current value from the option menu choice
	gchar *label;
	option_type *opt;
	opt = (option_type *) data;
	if (!GTK_CHECK_MENU_ITEM(wdg)->active) {
		return;
	}
	if (!GTK_IS_LABEL(GTK_BIN(opt->widget)->child))
	// First call, label not available (!), opt->value is already initialized
		return;
	gtk_label_get(GTK_LABEL(GTK_BIN(opt->widget)->child ),&label);
	if (!strcmp(label,_(NO_VALUE)))
		opt->value[0] = '\0';  // Empty string
	else
	// opt->value is already allocated with the max label length
		strcpy(opt->value, label);
}
/**************************************************/

Here is how I create the option menu (first item shown, I loop for the 
others after - it should be pretty standard):

/**************************************************/
	(...)
	GSList *group = NULL;
	GtkWidget *menu, *menuitem;

	opt->widget = gtk_option_menu_new();
	menu = gtk_menu_new();
	gtk_option_menu_set_menu (GTK_OPTION_MENU(opt->widget),menu);
	gtk_widget_show(opt->widget);
	menuitem = gtk_radio_menu_item_new_with_label (group,NO_VALUE);
	group =
	    gtk_radio_menu_item_group(GTK_RADIO_MENU_ITEM(menuitem));
	gtk_menu_append(GTK_MENU(menu),menuitem);
	gtk_widget_show(menuitem);
	gtk_signal_connect(GTK_OBJECT(menuitem), "activate",
		GTK_SIGNAL_FUNC(omenu_callb), (gpointer) opt);
	(...)
/**************************************************/

Now here is how I set the option menu item from a label - it could give 
you some hint on how you can "dig" inside the option menu:

/**************************************************/
void set_option_menu_from_label (GtkWidget *omenu, gchar *label) {
	GtkWidget *menu;
	GList *node;
	gchar *txt;
	if (GTK_IS_LABEL(GTK_BIN(omenu)->child)) {
		gtk_label_get(GTK_LABEL(GTK_BIN(omenu)->child), &txt);
		if (!strcmp(txt,label))  // Nothing to do, the label is already set
			return;
	}
	menu = gtk_option_menu_get_menu(GTK_OPTION_MENU(omenu));
	node = GTK_MENU_SHELL(menu)->children;
	while (node) {
		if (GTK_IS_LABEL(GTK_BIN(node->data)->child)) {
			gtk_label_get(GTK_LABEL(GTK_BIN(node->data)->child), &txt);
			if (!strcmp(txt,label))
				break;
		} // If the child is not a label (typically it would be NULL),
		 // we skip it because the menu item is the current one
		node = node->next;
	}
	if (node)	{	// Label found
		gtk_menu_item_activate(GTK_MENU_ITEM(node->data));
		gtk_option_menu_set_history(GTK_OPTION_MENU(omenu),
			g_list_index(GTK_MENU_SHELL(menu)->children, node->data));
	}
	else {		// Label not found, revert to default
		gtk_menu_item_activate(GTK_MENU_ITEM(GTK_MENU_SHELL(menu)->children->data));
		gtk_option_menu_set_history(GTK_OPTION_MENU(omenu),0);
	}
}
/**************************************************/

I wouldn't be able to explain all the details right away, I've done it 
by trial and error some time ago. Hoping this could help, BTW.

Best regards,

Patrice St-Gelais