I have this model for a map of maps in Firebase.

class Names {
  UserInformationModelMap names;
  Names({
    required this.names,
  });

  Map<String, dynamic> toMap() {
    return <String, dynamic>{
      'names': names.toMap(),
    };
  }

  factory Names.fromMap(Map<String, dynamic> map) {
    return Names(
      names: UserInformationModelMap.fromMap(
        map['names'] as Map<String, dynamic>,
      ),
    );
  }

  factory Names.fromSnapshot(DocumentSnapshot<Map<String, dynamic>> doc) {
    return Names(
      names: UserInformationModelMap.fromSnapshot(
        doc,
      ),
    );
  }
}'

class UserInformationModelMap {
  WholeNameMap fullName;
  String? uid;
  UserInformationModelMap({
    required this.fullName,
    this.uid,
  });

  Map<String, dynamic> toMap() {
    return <String, dynamic>{
      uid!: fullName.toMap(),
    };
  }

  factory UserInformationModelMap.fromMap(Map<String, dynamic> map) {
    return UserInformationModelMap(
      fullName: WholeNameMap.fromMap(map['fullName'] as Map<String, dynamic>),
    );
  }

  factory UserInformationModelMap.fromSnapshot(
      DocumentSnapshot<Map<String, dynamic>> doc) {
    return UserInformationModelMap(
      fullName: WholeNameMap.fromMap(doc['fullName'] as Map<String, dynamic>),
    );
  }
}

class WholeNameMap {
  String firstName;
  String lastName;

  WholeNameMap({
    required this.firstName,
    required this.lastName,
  });

  Map<String, dynamic> toMap() {
    return <String, dynamic>{
      'firstName': firstName,
      'lastName': lastName,
    };
  }

  factory WholeNameMap.fromMap(Map<String, dynamic> map) {
    return WholeNameMap(
      firstName: map['firstName'] as String,
      lastName: map['lastName'] as String,
    );
  }
}

This enables me to upload information into Firebase which is a map of maps. You can refer to the image to see how it looks like.

Here’s how it looks like on Firebase.

Now, what I wanted to achieve is to query the data from the Firebase and show in on my application using a ListViewBuilder.

Can anyone help me fix my model? Specifically fromSnapshot since that is where the querying happens.

Here’s what I get when querying.

Many thanks!