diff --git a/app/src/main/java/com/example/tampopo_client/views/MainActivity.java b/app/src/main/java/com/example/tampopo_client/views/MainActivity.java
index 624dec0..19dca60 100644
--- a/app/src/main/java/com/example/tampopo_client/views/MainActivity.java
+++ b/app/src/main/java/com/example/tampopo_client/views/MainActivity.java
@@ -135,8 +135,11 @@
 
         for (String friendId: userViews.keySet()) {
             final String updateFriendId = friendId;
-            MutableLiveData<List<Activity>> activitiesLiveData = activityViewModel.getActivitiesLiveDataFromUserId(friendId);
-            activitiesLiveData.observe(this, new Observer<List<Activity>>() {
+            MutableLiveData<List<Activity>> activitiesLiveData = activityViewModel.getActivitiesLiveDataFromUserId(updateFriendId);
+            FriendIconView friendView = userViews.get(friendId);
+            if(friendView == null) continue;
+            //activitiesLiveData.observeForever(friendView);
+            activitiesLiveData.observeForever(new Observer<List<Activity>>() {
                 @Override
                 public void onChanged(List<Activity> activities) {
                     // 更新したフレンドの再登場，更新してないフレンドの退場」
@@ -148,7 +151,7 @@
                     }
                 }
             });
-            activitiesLiveData.observe(this, userViews.get(friendId));
+            //activitiesLiveData.observe(this, userViews.get(friendId));
         }
 
         //メイン画面から通知一覧画面への遷移