submenu signal not working

[Denis <world of micro world gmail com>]

Signal of submenu not called while i not clicked to
main_menu->sub_menu->sum_menu_item

but i what to click menu_menu_button->sub_menu_item

GtkWidget* menu;
GtkWidget* menu_item;
GtkWidget* sub_menu;

menu = gtk_menu_new();
menu_item = gtk_image_menu_item_new_with_label("Text");

g_signal_connect (menu_item, "activate", G_CALLBACK
(menu_item_activated_signal), NULL);
gtk_widget_show (menu_item);

gtk_menu_shell_append (GTK_MENU_SHELL (menu), menu_item);
    {
        sub_menu = gtk_menu_new();
        gtk_menu_item_set_submenu(GTK_MENU_ITEM(menu_item),sub_menu);

        menu_item = gtk_image_menu_item_new_with_label("Test");
        image=
gtk_image_new_from_stock(GTK_STOCK_REFRESH,GTK_ICON_SIZE_MENU);
        gtk_widget_show(image);

gtk_image_menu_item_set_image(GTK_IMAGE_MENU_ITEM(menu_item),image);
        g_signal_connect (menu_item, "activate", G_CALLBACK
(menu_item_activated_signal), NULL); //this is not called
        gtk_widget_show (menu_item);
      
        gtk_menu_shell_append (GTK_MENU_SHELL (sub_menu), menu_item);
    }