无法取消订阅 Firebase 中的侦听器

Question

I have a Listener set up in my Firebase Realtime Database that notices changes to data of the users friends. But when the user removes one of the friends from his friend list I want to unsubscribe from these data changes. I tried doing so like in the following:

databaseReference.Child("usernames").Child(removedFriendName)
.ChildChanged -= HandleChildChangedFriend;

The reference and path to the database are exactly the same as they were when I subscribed to changes of the data. However, after a user removes someone from his friendlist he still receives updates from this EventListener.

Hope someone can help me with this :)

Answer 1

Okay I finally found a solution to make my code work, yet I still don't understand why it didnt work before. Doesn't matter I guess :)

The one thing I changed was that I saved the databaseReference inside a variable at the moment I added the EventListener and then later on used this variable again to remove the listener.

DatabaseReference friendReference = databaseReference.Child("usernames").Child(friendName);

friendReference.ChildChanged += HandleChildChangedFriend;

//Later 

friendReference.ChildChanged -= HandleChildChangedFriend;