protected override bool OnButtonPressEvent(Gdk.EventButton evb)
{
if (evb.Type == Gdk.EventType.ButtonPress && evb.Button == 1) {
clickX = (int)evb.XRoot;
clickY = (int)evb.YRoot;
localClickX = (int) evb.X;
localClickY = (int) evb.Y;
}
return true;
}