public static void gtk_window_set_titlebar(IntPtr window, IntPtr widget) { if (EtoEnvironment.Platform.IsLinux) { NMLinux.gtk_window_set_titlebar(window, widget); } else if (EtoEnvironment.Platform.IsMac) { NMMac.gtk_window_set_titlebar(window, widget); } else { NMWindows.gtk_window_set_titlebar(window, widget); } }