adding black overlay with 0.3 opacity over UIImageView

Question

I have a UIImageView and I wanted to add a black overlay on top of it. What is the best way of doing this without having to override drawRect? I was thinking of adding a CALayer

Answer 1

Swift 5 Version:

func addOverlay(on view: UIView) {
    let overlay: UIView = UIView(frame: CGRect(x: 0, y: 0, width: view.frame.size.width, height: view.frame.size.height))
    overlay.backgroundColor = UIColor.gray
    view.addSubview(overlay)
}