Alert View contains Security Text Field that auto detects verification code from Messages.

SecurityCodeTextField.swift

/* The verification code SMS must follow this model:
*   "Your verification code: XXXXXX"
* You can localize it 
*   "Doğrulama kodunuz: 123456"
* but the important part is; 
* the ":" character and the code must position at the end.
* Otherwise the textfield won't recognize it.
*/

let ac = UIAlertController(title: "Verification Code", message: "Enter the code.", preferredStyle: .alert)

ac.addTextField { (securityCodeTextField : UITextField!) -> Void in
    securityCodeTextField.textContentType = .oneTimeCode
}

let submitAction = UIAlertAction(title: "Done", style: .default) { [unowned ac] _ in
    let answer = ac.textFields![0].text
    
    // Do anything with the verification code
}

let cancelAction = UIAlertAction(title: "Cancel", style: UIAlertAction.Style.destructive, handler: nil)

ac.addAction(submitAction)
ac.addAction(cancelAction)

self.present(ac, animated: true)