protected function findModel($id)
 {
     if (($model = ApplicationConfig::findOne($id)) !== null) {
         return $model;
     } else {
         throw new NotFoundHttpException('The requested page does not exist.');
     }
 }
 public function actionIndex()
 {
     $visitor = ApplicationConfig::findOne(1);
     return $this->render('index', ['visitor' => $visitor]);
 }