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Dart wrapper for Firebase
https://pub.dev/packages/firebase
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Stream listen is not called when limit is added in Firestore query in Dart / Flutter #394

Open kamleshwebtech opened 3 years ago

kamleshwebtech commented 3 years ago

Stream listen is not called when limit is added in Firestore query in Dart / Flutter

I have used below code in my initState() function:

Stream<QuerySnapshot> xstream = FirebaseFirestore.instance
      .collection('messages')
      .where('encSenderUId', isEqualTo: _loggedInUserId)
      .where('encReceiverUId', isEqualTo: widget.encUId)
      .orderBy('messageId', descending: true)
      .startAt([_startAtTimestamp])
      .limit(1)
      .snapshots();

  xstream.listen((event) {   
    print('Hiii, I am listening..');

  }, onDone: () {
    print("Task Done single");

  }, onError: (error) {
    print("Some Error ${error.toString()}");

  });

Case 1: If I DO NOT use limit() in query then listen message is printed once when screen is rendered first time and also listen is called when something is changed in Firestore stream (eg. added new document / removed a document).

Case 2: If I use limit() in query then listen message is printed once when screen is rendered first time but listen is NOT called when something is changed in Firestore stream (eg. added new document / removed a document).

I have to use limit() to fetch one document according to set orderBy. I am 100% sure that limit() is not allowing stream to listen any event.

Kindly suggest how can I use limit with `listen' to fix this issue. Thanks a lot.