UIManager.ensureUpdate

Makes sure that all pending updates to the UI have been completed.

This may occasionally be necessary, since #GtkUIManager updates the UI in an idle function. A typical example where this function is useful is to enforce that the menubar and toolbar have been added to the main window before showing it:

gtk_container_add (GTK_CONTAINER (window), vbox);
g_signal_connect (merge, "add-widget",
                 G_CALLBACK (add_widget), vbox);
gtk_ui_manager_add_ui_from_file (merge, "my-menus");
gtk_ui_manager_add_ui_from_file (merge, "my-toolbars");
gtk_ui_manager_ensure_update (merge);
gtk_widget_show (window);