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 bebcc2c..a8c0de4 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
@@ -318,7 +318,7 @@
 
             // Observerがまだ登録されていない場合は登録する
             if (!userView.isActivityObserverRegistered()) {
-                activitiesLiveData.observeForever(userView.getActivitiesObserver());
+                activitiesLiveData.observe(this, userView.getActivitiesObserver());
                 userView.setActivityObserverRegistered(true);
             }