Create Alert View Controller (Swift 4)

let alert = UIAlertController(title: "Title", message: nil, preferredStyle: .alert)
alert.addTextField { (textField) in
        textField.placeholder = "Name"
    }

let action = UIAlertAction(title: "Save", style: .default) { (_) in 
}

let cancel = UIAlertAction(title: "Cancel", style: .cancel) { (action: UIAlertAction) in
    }

alert.addAction(action)
    alert.addAction(cancel)

present(alert, animated: true, completion: nil)