public void Show (Xwt.Popover.Position orientation, Xwt.Widget referenceWidget, Xwt.Rectangle positionRect, Xwt.Widget child)
{
popover = MakePopover (child, BackgroundColor);
ViewBackend backend = (ViewBackend)Toolkit.GetBackend (referenceWidget);
var reference = backend.Widget;
// If the position rect is empty, the coordinates of the rect will be ignored.
// Width and Height of the rect must be > Epsilon, for the positioning to function correctly.
if (Math.Abs (positionRect.Width) < double.Epsilon)
positionRect.Width = 1;
if (Math.Abs (positionRect.Height) < double.Epsilon)
positionRect.Height = 1;
popover.Show (positionRect.ToCGRect (),
reference,
ToRectEdge (orientation));
}