public function actionIndex($parent_id = 1) { $searchModel = new Navigation(['scenario' => 'search']); $searchModel->parent_id = $parent_id; $dataProvider = $searchModel->search($_GET); $model = null; if ($parent_id > 0) { $model = Navigation::findOne($parent_id); } return $this->render('index', ['dataProvider' => $dataProvider, 'searchModel' => $searchModel, 'model' => $model]); }