changeRows.swift

@IBAction func changeRows(_ sender: UIStepper) {
    let alert = UIAlertController(title: "", message: "Your password will be cleared. Do you want to continue?", preferredStyle: .alert)
    let continueAction = UIAlertAction(title: "Continue", style: .default) { [weak self](_) in
        self?.row = Int(sender.value)
        self?.password = []
        self?.gestureCollectionView.reloadSections(IndexSet(integer: 0))
    }
    let cancelAction = UIAlertAction(title: "Cancel", style: .cancel, handler: nil)
    alert.addAction(continueAction)
    alert.addAction(cancelAction)
    self.present(alert, animated: true, completion: nil)
}