Flutter - Can´t iterate model values-CodePudding

In Flutter i have this model

class UserModel {
  final int id;
  final String name;
  final String email;
  final String language;
  final String city;
  final double latitude;
  final double longitude;

  UserModel(
      {required this.id,
      required this.name,
      required this.email,
      required this.language,
      required this.city,
      required this.latitude,
      required this.longitude});

  factory UserModel.fromJson(Map<String, dynamic> json) {
    return UserModel(
      id: json['id'] ?? 0,
      name: json['name'],
      email: json['email'],
      language: json['language'],
      city: json['city'],
      latitude: json['latitude'],
      longitude: json['longitude'],
    );
  }
}

Then in service i hace two functions

  Future getAllSimple() async {
    var url = Uri.parse('http://10.0.2.2:80/users/all');
    var response = await http.get(url);
    if (response.statusCode == 200) {
      return jsonDecode(response.body);
    } else {
      throw Exception('Error: ${response.statusCode}.');
    }
  }

  Future<UserModel> getAll() async {
    var url = Uri.parse('http://10.0.2.2:80/users/all');
    var response = await http.get(url);
    if (response.statusCode == 200) {
      return UserModel.fromJson(jsonDecode(response.body));
    } else {
      throw Exception('Error: ${response.statusCode}.');
    }
  }

In controller this works

  Future getMarkers() async {
    UserService().getAllSimple().then((value) { // Here
      setState(() {
        value.forEach((key, element) {
          _markers.add(Marker(
            markerId: MarkerId(element['id']),
            position: LatLng(element['latitude'], element['longitude']),
            infoWindow: InfoWindow(
              title: element['name'],
            ),
            icon: BitmapDescriptor.defaultMarker,
          ));
        });
      });
    }).catchError((e) {
      debugPrint(e);
    });
  }

But if i try to use getAll i can't do foreach because is a model map. Anybody know how can i convert model to can do foreach over all values?

CodePudding user response：

According to user provided codes for controller, your api call will return list of json data. So you may follow these steps:

Create a json list data parser method

List<UserModel> usersFromJson(String body) =>
    List<UserModel>.from(jsonDecode(body).map((x) => UserModel.fromJson(x)));

Use usersFromJson method to return the List

Future<List<UserModel>> getAll() async {
    var url = Uri.parse('http://10.0.2.2:80/users/all');
    var response = await http.get(url);
    if (response.statusCode == 200) {
      return usersFromJson(response.body);
    } else {
      throw Exception('Error: ${response.statusCode}.');
    }
  }

Call the getMarkers() method and iterate the list of users

  Future getMarkers() async {
    UserService().getAll().then((value) { // Here

      if(value != null && value is List<UserModel>) {
        setState(() {
          for (var element in value) {
            _markers.add(Marker(
              markerId: MarkerId(element.id),
              position: LatLng(element.latitude, element.longitude),
              infoWindow: InfoWindow(
                title: element.name,
              ),
              icon: BitmapDescriptor.defaultMarker,
            ));
          }
        });
      } else {
        log("value is null or not List<UserModel>")
      }
    }).catchError((e) {
      debugPrint(e);
    });
  }