     let elements: [ElementProtocol]
 
     var animator = HYModalAlertAnimator()
-    private var alertView: AlertView?
+    private let alertView: AlertView
 
     private weak var presentingVC: UIViewController?
 


extension Heyou: HYPresentationAnimatable {
    var topView: UIView {
        guard let view = alertView else { assertionFailure("alertView is nil"); return UIView() }
        return view
    }
    var backgroundView: UIView {
        return view

    }

    func configureAlertView() {
        view.addSubview(alertView)

        NSLayoutConstraint.activate([
