Flutter：如何在不覆盖的情况下使用一个文档在 Firestore 中添加多个字段

Question

我的项目现在有问题。我知道，很多人已经发布了这个问题，但我真的不知道如何在我的代码中实现它。我想做的是，使用一个文档在 Firestore 字段中添加多个数据。在字段中，有一个字段名称“Issue”，在“Issue”里面我有很多数据。每次我在该文档中添加新数据时，它都会覆盖该字段中的数据。如何在不覆盖的情况下添加数据，请帮助。

这是我的代码：

_saveIssueToActivities(dynamic data) async {
final FirebaseAuth _firebaseAuth = FirebaseAuth.instance;
final FirebaseUser user = await _firebaseAuth.currentUser();
try {
  DocumentReference ref = db.collection('ACTIVITIES').document(user.uid);
  return ref.setData({
  'Issue': {
    'User_ID': '',
    'Name_ofUser': '${data['Name_ofUser']}',
    'Help_Description': '${data['Help_Description']}',
    'Help_DatePosted:': '',
    'Help_Location': '',
    'Help_TypeNeeded': '${data['Help_TypeNeeded']}',
    'Help_NotificationID': '',
  }
  });
} catch (e) {
  print(e);
}

}

这是我的数据库结构：

Link to my db pic

Answer 1

尝试：

Future<dynamic> addDataToFirestore(dynamic data) async {
final FirebaseAuth _firebaseAuth = FirebaseAuth.instance;
final FirebaseUser user = await _firebaseAuth.currentUser();
DocumentReference ref = db.collection('ACTIVITIES').document(user.uid);
dynamic datatoSubmit = [{
    'User_ID': '',
    'Name_ofUser': '${data['Name_ofUser']}',
    'Help_Description': '${data['Help_Description']}',
    'Help_DatePosted:': '',
    'Help_Location': '',
    'Help_TypeNeeded': '${data['Help_TypeNeeded']}',
    'Help_NotificationID': ''
}];
   //Do some debugging with the datatypes or which type of data you have in the firebase document.

await ref.updateData({'Issue': FieldValue.arrayUnion(datatoSubmit)});

}


Or


Future<dynamic> addDataToFirestore(dynamic data) async {
final FirebaseAuth _firebaseAuth = FirebaseAuth.instance;
final FirebaseUser user = await _firebaseAuth.currentUser();
DocumentReference ref = db.collection('ACTIVITIES').document(user.uid);
dynamic datatoSubmit = {
    'User_ID': '',
    'Name_ofUser': '${data['Name_ofUser']}',
    'Help_Description': '${data['Help_Description']}',
    'Help_DatePosted:': '',
    'Help_Location': '',
    'Help_TypeNeeded': '${data['Help_TypeNeeded']}',
    'Help_NotificationID': ''
};
   //Do some debugging with the datatypes or which type of data you have in the firebase document.

await ref.updateData({'Issue': FieldValue.arrayUnion(datatoSubmit)});

}

这是我第二个例子的结果：