public function onConfirmationChanged($event)
    {
        $sender = $event->sender;
        $cAttribute = $sender->confirmationAttribute;
        if (!$cAttribute || empty($cAttribute)) {
            return;
        }
        if ($sender->isAttributeChanged($cAttribute)) {
            $sender->confirmCode = '';
            if ($sender->$cAttribute == static::$confirmFalse) {
                $sender->trigger(static::$eventConfirmationCanceled);
                return;
            }
            $sender->trigger(static::$eventConfirmationSuceeded);
            $sender->resetOthersConfirmation();
        }
    }