public function actionEdit()
 {
     $page = CustomPage::findOne(['id' => Yii::$app->request->get('id')]);
     if ($page === null) {
         $page = new CustomPage();
     }
     if ($page->load(Yii::$app->request->post()) && $page->validate() && $page->save()) {
         return $this->redirect(['index']);
     }
     return $this->render('edit', array('page' => $page));
 }