/**
  * Creates a new Slides model.
  * If creation is successful, the browser will be redirected to the 'view' page.
  * @return mixed
  */
 public function actionCreate($slider_id)
 {
     $model = new Slides();
     //check that slider exist
     if (Sliders::findOne($slider_id)) {
         //load model
         $load_mark = $model->load(Yii::$app->request->post());
         // inject slider_id
         $model->slider_id = $slider_id;
         if ($load_mark && $model->save()) {
             return $this->redirect(['sliders/update', 'id' => $model->slider_id]);
         }
     }
     return $this->render('create', ['model' => $model]);
 }