Detecção do cursor em uma view

PointerInView.swift

class ViewController: UIViewController {

    @IBOutlet var button: UIButton!

    override func viewDidLoad() {
        super.viewDidLoad()

        let hover = UIHoverGestureRecognizer(target: self, action: #selector(hovering(_:)))
        button.addGestureRecognizer(hover)
    }

    @objc
    func hovering(_ recognizer: UIHoverGestureRecognizer) {
        switch recognizer.state {
        case .began, .changed:
            button.titleLabel?.textColor = #colorLiteral(red: 1, green: 0, blue: 0, alpha: 1)
        case .ended:
            button.titleLabel?.textColor = UIColor.link
        default:
            break
        }
    }
}