/**
  * @inheritdoc
  */
 public function insert($runValidation = true, $attributeNames = null)
 {
     $changedAttributes = $this->getDirtyAttributes($attributeNames);
     if (empty($changedAttributes)) {
         $this->afterSave(false, $changedAttributes);
         return 0;
     }
     return parent::insert($runValidation, $attributeNames);
 }