class ViewController: UIViewController {

    @IBOutlet weak var cardNumberView: CreditCardValidatorView!

    override func viewDidLoad() {
        super.viewDidLoad()
        cardNumberView.delegate = self
    }
}

extension ViewController: CreditCardValidatorViewDelegate {
    func didEdit(number: String) {
        // Play with card number
    }

    func didEdit(expiryDate: String) {
        // Play with expiry date
    }

    func didEdit(cvc: String) {
        // Play with cvc
    }
}