public function actionSaveFilemanagerFolderState()
    {
        $folderId = Yii::$app->request->getBodyParam('folderId');
        
        if ($folderId) {
            return Yii::$app->adminuser->identity->setting->set('filemanagerFolderId', $folderId);
        } else {
            return Yii::$app->adminuser->identity->setting->remove('filemanagerFolderId');
        }
    }