Add just a top border to an UIView with Quartzcore/layer?

Question

Is it possible to add a border just on top of a UIView, if so, how please?

Answer 1

GilbertOOI's answer in Swift 4:

let topBorder: CALayer = CALayer()
topBorder.frame = CGRect(x: 0, y: 0, width: myView.frame.size.width, height: 1)
topBorder.backgroundColor = UIColor.purple.cgColor
myView.layer.addSublayer(topBorder)