yii\base\ActionFilter::afterAction PHP Method

    public function afterAction($action, $result)
    {
        return $result;
    }

 public function afterAction($action, $result)
 {
     $res = parent::afterAction($action, $result);
     if ($this->ajaxMode) {
         if ($res) {
             $dom = Yii::createObject(['class' => Dom::className(), 'html' => $res]);
             if (!empty($_REQUEST['target_id'])) {
                 $target_id = explode(',', $_REQUEST['target_id']);
                 $this->ajaxVars['html'] = $dom->getElementByIds($target_id);
             }
             list($scripts, $src) = $dom->getScripts();
             if ($scripts) {
                 $this->ajaxVars['scripts'] = $scripts;
             }
             if ($src && 0) {
                 // disabled
                 $this->ajaxVars['scripts_src'] = $src;
             }
         }
         // Flashes
         if (!isset($this->ajaxVars['alerts'])) {
             $this->ajaxVars['alerts'] = Yii::$app->session->getAllFlashes();
         }
         Yii::$app->response->format = 'json';
         return $this->ajaxVars;
     }
     return $res;
 }