title: How to listen firebase updates in real time in Flutter
body: <p>I have a stream which read user data from firebase. I trigger it after signin, it works perfectly. I show the data in my appbar. When I update firebase manually, I want to see the new date instantly on my appbar. First, I guessed there is something wrong with my appbar but then I noticed that my stream do not triggered when I update firebase data. Here is my stream code snippet. What am I missing?</p>
  
  <pre><code>static Future&lt;User&gt; userDataStream(userID) async {
      print("userDataStream");
  
      final databaseReference = Firestore.instance;
      User currentUser = User();
  
      await for (var snapshot in databaseReference
          .collection('users')
          .where('userID', isEqualTo: userID)
          .snapshots()) {
        currentUser.userName = snapshot.documents.first.data['userName'];
        currentUser.email = snapshot.documents.first.data['email'];
        currentUser.userID = snapshot.documents.first.data['userID'];
        currentUser.level = snapshot.documents.first.data['level'];
        currentUser.balance = snapshot.documents.first.data['balance'];
  
        print(currentUser.balance);
  
        return currentUser;
      }
  
      return currentUser;
    }
  </code></pre>