void InitIcons()
{
// could use this.RenderIcon(...) but those icons can be less appealing (grey check mark, red cross)
Gtk.Image image = new Gtk.Image ();
pixbufs [0] = image.RenderIcon (Gtk.Stock.No, IconSize.SmallToolbar, null);
pixbufs [1] = image.RenderIcon (Gtk.Stock.Yes, IconSize.SmallToolbar, null);
image.Destroy ();
}