Question

我收到此错误。我很生气。

Stream<List<TestModel>> awayStream() async* {
List<TestModel> retVal = <TestModel>[];
_categoryCollectionReferance.once().then((DataSnapshot dataSnapshot) {
  print(dataSnapshot.value);
  retVal.add(TestModel.fromJson(dataSnapshot.value));
  return retVal;
});}

错误：[ERROR:flutter/lib/ui/ui_dart_state.cc(199)] Unhandled Exception: type '_InternalLinkedHashMap<Object?, Object?>' is not a subtype of type 'Map<String, dynamic>'

print(dataSnapshot.value); -- this perfectly working.

但是我不能添加到列表中。这是我的型号代码；

TestModel.fromSnapshot(DataSnapshot dataSnapshot) {
awayCurrentUser = dataSnapshot.value['awayCurrentUser'] ?? 0;
awayDate = dataSnapshot.value['awayDate'] ?? 0;
awayID = dataSnapshot.value['awayID'] ?? '';
awayMaxUser = dataSnapshot.value['awayMaxUser'] ?? 0;
awayPhotoUrl = dataSnapshot.value['awayPhotoUrl'] ?? '';
awayPrice = dataSnapshot.value['awayPrice'] ?? 0;
awayTitle = dataSnapshot.value['awayTitle'] ?? '';
awayUserPrice = dataSnapshot.value['awayUserPrice'] ?? 0;
awayWinner = dataSnapshot.value['awayWinner'] ?? '';
awayWinnerName = dataSnapshot.value['awayWinnerName'] ?? '';
isEnabled = dataSnapshot.value['isEnabled'] ?? true;
isFinished = dataSnapshot.value['isFinished'] ?? false;
isStatus = dataSnapshot.value['isStatus'] ?? true;

}

Answer 1

这是因为 datasnapShot 不是“Map”类型或其子类型，在访问内部对象之前对其进行解码

试试这个

dataSnapshotDecoded=json.decode(dataSnapshot.value);

 retVal.add(TestModel.fromJson(dataSnapshotDecoded))

颤振实时数据库 'InternalLinkedHashMap<Object?, Object?>' 这个错误

1 个答案: