static void Modify_cb(IntPtr inst, IntPtr child_model, IntPtr iter, IntPtr value, int column)
 {
     try {
         TreeModelFilter __obj = GLib.Object.GetObject(inst, false) as TreeModelFilter;
         __obj.OnModify(Gtk.TreeModelAdapter.GetObject(child_model, false), Gtk.TreeIter.New(iter), (GLib.Value)Marshal.PtrToStructure(value, typeof(GLib.Value)), column);
     } catch (Exception e) {
         GLib.ExceptionManager.RaiseUnhandledException(e, false);
     }
 }