private void on_singletap(UITapGestureRecognizer gr)
{
var wh = gr.LocationInView(this);
_dp.do_singletap(wh.X, wh.Y);
}
public bool OnSingleTapConfirmed(MotionEvent ev)
{
//global::Android.Util.Log.Info ("dp OnSingleTapConfirmed", ev.ToString ());
return(_dp.do_singletap(ev.GetX(), ev.GetY()));
}