public function actionIndex()
 {
     if (Yii::$app->user->isGuest) {
         $userBibi = UserBibi::getAllDisplayUser();
         return $this->render('index', ['userBibi' => $userBibi]);
     } else {
         $mySchedule = Activity::getJoinActivity();
         $newPost = new Post();
         $sentPost = false;
         if ($newPost->load(Yii::$app->request->post())) {
             $newPost->datetime = date("Y-m-d H:i:s");
             $newPost->Participant_id = Yii::$app->user->id;
             if ($newPost->save()) {
                 $sentPost = true;
             }
         }
         return $this->render('myindex', ['schedule' => $mySchedule, 'newPost' => $newPost, 'sentPost' => $sentPost]);
     }
 }