void CreateDropdownLayer() { dropdownLayer = CALayer.Create(); dropdownLayer.Bounds = new RectangleF(0, 0, Width, items.Count * Font.LineSize); dropdownLayer.Delegate = new ComboBoxElementDropdownLayerDelegate(this); dropdownLayer.BackgroundColor = new CGColor(0, 0, 0, 1); dropdownLayer.BorderWidth = 1; dropdownLayer.BorderColor = new CGColor(1, 1, 0, 1); dropdownLayer.SetNeedsDisplay(); ParentScreen.AddSublayer(dropdownLayer); }