protected virtual void RenderPlaceholderText(object o, Gtk.ExposeEventArgs args)
        {
            var w = TextView.GetWindow(Gtk.TextWindowType.Text);

            if (!string.IsNullOrEmpty(PlaceholderText) && string.IsNullOrEmpty(Text) && args.Event.Window == w)
            {
                Util.RenderPlaceholderText(TextView, args, PlaceholderText, ref layout);
            }
        }