diff --git a/app/src/main/java/com/example/tampopo_client/models/Activity.java b/app/src/main/java/com/example/tampopo_client/models/Activity.java
index 7c3d626..6dcf984 100644
--- a/app/src/main/java/com/example/tampopo_client/models/Activity.java
+++ b/app/src/main/java/com/example/tampopo_client/models/Activity.java
@@ -13,6 +13,9 @@
         this.updateTime = updateTime;
     }
 
+    public Activity() {
+    }
+
     public String getUserId() {
         return userId;
     }
diff --git a/app/src/main/java/com/example/tampopo_client/viewmodels/ActivityViewModel.java b/app/src/main/java/com/example/tampopo_client/viewmodels/ActivityViewModel.java
index 3df02a7..979f251 100644
--- a/app/src/main/java/com/example/tampopo_client/viewmodels/ActivityViewModel.java
+++ b/app/src/main/java/com/example/tampopo_client/viewmodels/ActivityViewModel.java
@@ -62,7 +62,7 @@
         activitiesResource = retrofit.create(ActivitiesResource.class);
         userResource = retrofit.create(UserResource.class);
 
-        friendToActivitiesLiveData = Map.of();
+        friendToActivitiesLiveData = new HashMap<>();
         friendUserIdsLiveData = new MutableLiveData<>(List.of());
         myLatestActivityLiveData = new MutableLiveData<>(null);
 
@@ -146,9 +146,6 @@
         assert userActivitiesLiveData != null;
 
         List<Activity> userActivities = userActivitiesLiveData.getValue();
-        if (userActivities == null) {
-            return;
-        }
 
         if (userActivities.isEmpty()) {
             userActivitiesLiveData.postValue(List.of(latestActivity));
@@ -263,27 +260,29 @@
             @Override
             public void onResponse(@NonNull Call<List<String>> call, @NonNull Response<List<String>> response) {
                 if (response.isSuccessful()) {
-                    friendUserIdsLiveData.postValue(response.body());
 
                     // MEMO: 入れ込んだだけ
                     // フレンドのIDをアクティビティ更新順に並べ替える
                     List<String> friendUserIds = friendUserIdsLiveData.getValue();
-                    SortedSet<Friend> friends = new TreeSet<>(new Friend.UpdateTimeComparator());
+                    if (friendUserIds == null || !friendUserIds.equals(response.body())) {
+                        friendUserIdsLiveData.postValue(response.body());
+                        SortedSet<Friend> friends = new TreeSet<>(new Friend.UpdateTimeComparator());
 
-                    assert friendUserIds != null;
-                    friendUserIds.forEach(userId -> {
-                        List<Activity> activities = getActivitiesLiveDataFromUserId(userId).getValue();
-                        if (activities == null || activities.isEmpty()) {
-                            return;
-                        }
+                        assert friendUserIds != null;
+                        friendUserIds.forEach(userId -> {
+                            List<Activity> activities = getActivitiesLiveDataFromUserId(userId).getValue();
+                            if (activities == null || activities.isEmpty()) {
+                                return;
+                            }
 
-                        Activity latestActivity = activities.get(0);
-                        friends.add(new Friend(userId, latestActivity.getUpdateTime()));
-                    });
+                            Activity latestActivity = activities.get(0);
+                            friends.add(new Friend(userId, latestActivity.getUpdateTime()));
+                        });
 
-                    // 並び替えたフレンドのユーザーIDを順番に格納して更新する
-                    sortedFriendUserIds.clear();
-                    friends.forEach(friend -> sortedFriendUserIds.add(friend.getUserId()));
+                        // 並び替えたフレンドのユーザーIDを順番に格納して更新する
+                        sortedFriendUserIds.clear();
+                        friends.forEach(friend -> sortedFriendUserIds.add(friend.getUserId()));
+                    }
                 }
             }
 
@@ -305,6 +304,9 @@
      * @return 取得対象のユーザーのアクティビティのリストのライブデータ
      */
     public MutableLiveData<List<Activity>> getActivitiesLiveDataFromUserId(String userId) {
+        if(!friendToActivitiesLiveData.containsKey(userId)){
+            friendToActivitiesLiveData.put(userId, new MutableLiveData<>());
+        }
         return friendToActivitiesLiveData.get(userId);
     }
 
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 29af578..d75baff 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
@@ -134,14 +134,24 @@
         });
 
         for (String friendId: userViews.keySet()) {
-            MutableLiveData<List<Activity>> activitiesLiveData = activityViewModel.getActivitiesLiveDataFromUserId(friendId);
-            activitiesLiveData.observe(this, new Observer<List<Activity>>() {
+            final String updateFriendId = friendId;
+            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」
+                    //更新した人を見つけてFriendIconViewを呼び出して、
+                    FriendIconView userView = userViews.get(updateFriendId);
+                    if (userView != null && activities != null && !activities.isEmpty()) {
+                        Activity latest = activities.get(activities.size() - 1);
+                        userView.setComment(latest.getText());
+                    }
                 }
             });
-            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
@@ -307,6 +317,8 @@
 //            Activity activity = entry;
 
             FriendIconView userView = userViews.get(friendId);
+            MutableLiveData<List<Activity>> activitiesLiveData = activityViewModel.getActivitiesLiveDataFromUserId(friendId);
+
 
             if (userView == null) {
                 // 新しいユーザなので、アイコン＋コメントを作成
@@ -341,6 +353,7 @@
                 // Mapに登録、画面に追加
                 userViews.put(friendId, container);
                 messageList.addView(container);
+                activitiesLiveData.observeForever(container);
 
 //            } else {
 //                // 既に表示されている → コメントだけ更新
@@ -510,11 +523,12 @@
 
         dialog.show();
     }
-
+//通知を受信したときのダイアログ　これが動いてます
+    //friendName+から通話があります。ってでるから通知が来たときのフレンドを変数に置く必要がある
     @Override
     public void onNotificationReceived() {
         // 通知を受信したときにダイアログを表示
-        runOnUiThread(() -> showChatNotification("user01"));
+        runOnUiThread(() -> showChatNotification("user02"));
         // アイコンを赤枠に
         runOnUiThread(() -> highlightUserIcon("user01"));
     }