GdkNativeWindowId and GtkWidget

[George Gugulea <gugulea gmail com>]

I have an application that allows me to get a GdkNativeWindowId and allows me to implement some callbacks to handle events.
I need to add GtkWidgets to that window.
One way would be to create a GdkWindow and set it to a GtkWidget (even a GtkWindow) but this doesn't work:

void create_window(GdkNativeWindow nativeWinId)
{
  GdkWindow* gdkWindow;
  gdkWindow = gdk_window_foreign_new(nativeWinId);

  GtkWidget *gtkVbox;
  gtkVbox = gtk_vbox_new (FALSE, 2);
  gtkVbox->window = gdkWindow;
  gtk_widget_show(gtkVbox);
}

I do this in a XEvent GraphicsExpose event handler.
-- 
gg