protected function initMessages()
    {
        if (!is_string($this->registerSuccessMessage)) {
            $this->registerSuccessMessage = Yii::t('user' ,'User Registered.');
        }
        if (!is_string($this->registerFailedMessage)) {
            $this->registerFailedMessage = Yii::t('user', 'Register Failed.');
        }
        if (!is_string($this->deregisterSuccessMessage)) {
            $this->deregisterSuccessMessage = Yii::t('user', 'User Deregistered.');
        }
        if (!is_string($this->deregisterFailedMessage)) {
            $this->deregisterFailedMessage = Yii::t('user', 'Failed to Deregister User.');
        }
        if (!is_string($this->updateSuccessMessage)) {
            $this->updateSuccessMessage = Yii::t('user', 'Updated.');
        }
        if (!is_string($this->updateFailedMessage)) {
            $this->updateFailedMessage = Yii::t('user', 'Failed to Update.');
        }
    }