observeFirestoreDocument method

ValueNotifier<Map<String, dynamic>?> observeFirestoreDocument(String documentPath)

Observes a Firestore document in real-time.

• documentPath: Path to the Firestore document.

Returns a ValueNotifier that emits updates whenever the document changes.

Implementation

ValueNotifier<Map<String, dynamic>?> observeFirestoreDocument(String documentPath) {
  final notifier = ValueNotifier<Map<String, dynamic>?>(null);
  final docRef = _firestore.doc(documentPath);

  final subscription = docRef.snapshots().listen((snapshot) {
    if (!snapshot.exists) {
      debugPrint('Document at $documentPath does not exist.');
      SchedulerBinding.instance.addPostFrameCallback((_) {
        notifier.value = null;
      });
      return;
    }

    final data = snapshot.data();
    SchedulerBinding.instance.addPostFrameCallback((_) {
      notifier.value = data;
    });
  }, onError: (error) {
    debugPrint('Error observing Firestore document at $documentPath: $error');
    SchedulerBinding.instance.addPostFrameCallback((_) {
      notifier.value = null;
    });
  });

  streams.add(subscription);

  notifier.addListener(() {
    if (!notifier.hasListeners) {
      subscription.cancel();
      debugPrint('Subscription canceled for $documentPath');
    }
  });

  return notifier;
}