void CreateControlPoint ()
{
var controlColor = touchDown ? TintColor.CGColor : UIColor.DarkGray.CGColor;
var lineLayer = new CALayer {
BackgroundColor = controlColor,
Name = "x"
};
controls.Add (lineLayer);
graphLayer.AddSublayer (lineLayer);
lineLayer = new CALayer {
BackgroundColor = controlColor,
Name = "y"
};
controls.Add (lineLayer);
graphLayer.AddSublayer (lineLayer);
var circleLayer = new CALayer {
BorderColor = controlColor,
BorderWidth = 2f,
CornerRadius = 3f,
Name = "point"
};
controls.Add (circleLayer);
graphLayer.AddSublayer (circleLayer);
}