flutterdartfirebase-realtime-database

Can't cast _InternalLinkedHashMap<Object?, Object?> to anything

I've been having some issues with get data from Firebase RealtimeDatabase as a Map despite me uploading it as a Map in the first place. All solutions I see are that you should just cast The snapshot.value to the data type incoming but no iteration of that works for me. I've been able to call toString() on the snapshot value and I've verified that it's a Map but the compiler doesn't even allow me to cast it to a Map let alone run it. If I try to use dynamic to prevent that compile error, I still get this Unhandled Exception: type '_InternalLinkedHashMap<Object?, Object?>' is not a subtype of type 'Map<String, dynamic>?' in type cast.

This is what I've done,

  Future<Map<String, dynamic>> getBasicDetail(
      DatabaseReference databaseReference) async {
    DatabaseReference imageURLevent = databaseReference.child('basicDetail');

    final snapShot = await imageURLevent.get();
    return Map<String, dynamic>.from(
        snapShot.value as Map<String, dynamic>? ?? {});
  }

  Future<void> readProfileData({required String userId}) async {

    DatabaseReference ref = FirebaseDatabase.instance.ref("users/$userId");

    final basicDetail = await getBasicDetail(ref);
    
    // Print the data of the snapshot
    debugPrint(basicDetail.toString());
  }

I've tried every possible combination of parsing this data but nothing works. For some reason in examples and videos when you cast the right hand side to Map<String,dynamic> you get no error but my IDE doesn't even allow me to do that. I've also tried Map.from() seems to be a popular one that works but mine simple throws a runtime error.

Why does this Firecasts from https://www.youtube.com/watch?v=sXBJZD0fBa4&ab_channel=Firebase

work while mine

Code doesn't?

event.snapshot.value looks valid too

[log] {bloodGroup: gh, imageURL: /data/user/0/com.piyushlimited.buzzai/app_flutter/image_picker7287835118545461685.jpg, fullName: Henry Nana Adu, weight: 523, dateOfBirth: 11/11/11, licenseNumber: 256489, age: 28}

I can access one value of data by referencing the full path to it but I have a large Map and I can't do it for each and every value in each and every category. It seems costly and time wasting. I've spent days trying a lot of things so please keep that in mind.

Solution

  • Thanks for your responses guys. Especially to @Stelios Papamichail for providing the solution 3 months ago. Firebase's response is not in a valid JSON format it seems It's a shame the official dev team hasn't taken notice of this. jsonDecode(jsonEncode(event.snapshot.value))); works perfectly. It's probably bad performance wise but I don't really care at this point I'm just happy it does. I don't know why it works either.

    This now works perfectly

      Future<void> readProfileData({required String userId}) async {
    DatabaseReference ref = FirebaseDatabase.instance.ref("users/$userId");

    try {
      final DataSnapshot? snapShot = await ref.get();

      Map<String, dynamic> data = jsonDecode(jsonEncode(snapShot?.value));

      userProfile = UserProfile.fromMap(data);

      setGender(userProfile.gender);

      notifyListeners();

      log(userProfile.toString());
    } on Exception catch (e) {
      log(e.toString());
    }
  }

    Hopefully more people see this and not waste their life like I have.