hi stackers i have a problem with returning nested data in array object using flutter, the data has shown but i cant get what i want to get i have a response like this from my backend

    "meta": {
        "code": 200,
        "status": "success",
        "message": "Data list transaksi berhasil diambil"
    },
    "data": {
        "current_page": 1,
        "data": [
            {
                "id": 1,
                "users_id": 1,
                "invoice": "INV38972",
                "seat_number": 2,
                "total_price": 1000,
                "payment_method": "TUNAI",
                "status": "PENDING",
                "items": [
                    {
                        "id": 1,
                        "menus_id": 1,
                        "transactions_id": 1,
                        "quantity": 5,
                        "menus": {
                            "id": 1,
                            "name": "Adidas NMD",
                            "price": 200,
                            "description": "Ini adalah sepatu sport",
                            "categories_id": 1,
                        }
                    }
                ]
            }
        ],
    }
}

response above is from my backend that success fully return in my response print() in flutter but i want to get the nested data in items.menus its return error Class'_InternalLinkedHashMap<String, dynamic>'has no instance getter 'menus'

for better understanding my question ill provide full model, provider and my services

this is my service getOrderList() function that i call in the futureBuilder

      var url = '$baseUrl/transaction';

      var headers = {
        'Content-type': 'application/json',
        'Authorization': 'Bearer ${userModel.token}'
      };

      var response = await http.get(Uri.parse(url), headers: headers);

      // print(response.body);
      // print('berhasil get kategori');

      if (response.statusCode == 200) {
        List data = json.decode(response.body)['data']['data'];
        List<TransactionModel> transaction = [];

        for (var item in data) {
          transaction.add(TransactionModel.fromJson(item));
        }
        // print(transaction);
        return transaction;
      } else {
        throw Exception('Gagal get Categori');
      }
    }

and this is my model code

class TransactionModel {
  int id;
  int users_id;
  String invoice;
  int seat_number;
  double total_price;
  String payment_method;
  String status;
  List items;
  // List menu;

  TransactionModel({
    this.id,
    this.users_id,
    this.invoice,
    this.seat_number,
    this.total_price,
    this.payment_method,
    this.status,
    this.items,
    // this.menu,
  });

  TransactionModel.fromJson(Map<String, dynamic> json) {
    id = json['id'];
    users_id = json['users_id'];
    invoice = json['invoice'];
    seat_number = json['seat_number'];
    total_price = double.parse(json['total_price'].toString());
    payment_method = json['payment_method'];
    status = json['status'];
    items = json['items'];
    // menu = json['items']['menus'];
  }

  Map<String, dynamic> toJson() {
    return {
      'id': id,
      'users_id': users_id,
      'invoice': invoice,
      'seat_number': seat_number,
      'items': items,
      'total_price': total_price,
      'payment_method': payment_method,
      'status': status,
      // 'menu': menu,
    };
  }
}

i already change the model data and try much method but its still not working, thats all on my code what should i do to call items.menus in result ?

CodePudding user response：

It seems to be a problem within the model, you can use a json to dart to make model class from raw json. Keep the fetching logic as it is.

Json

            {
                "id": 1,
                "users_id": 1,
                "invoice": "INV38972",
                "seat_number": 2,
                "total_price": 1000,
                "payment_method": "TUNAI",
                "status": "PENDING",
                "items": [
                    {
                        "id": 1,
                        "menus_id": 1,
                        "transactions_id": 1,
                        "quantity": 5,
                        "menus": {
                            "id": 1,
                            "name": "Adidas NMD",
                            "price": 200,
                            "description": "Ini adalah sepatu sport",
                            "categories_id": 1
                        }
                    }
                ]
            }
  

Model class

// To parse this JSON data, do
//
//     final transactionModel = transactionModelFromMap(jsonString);

import 'dart:convert';

class TransactionModel {
    TransactionModel({
        this.id,
        this.usersId,
        this.invoice,
        this.seatNumber,
        this.totalPrice,
        this.paymentMethod,
        this.status,
        this.items,
    });

    final int id;
    final int usersId;
    final String invoice;
    final int seatNumber;
    final int totalPrice;
    final String paymentMethod;
    final String status;
    final List<Item> items;

    factory TransactionModel.fromJson(String str) => TransactionModel.fromMap(json.decode(str));

    String toJson() => json.encode(toMap());

    factory TransactionModel.fromMap(Map<String, dynamic> json) => TransactionModel(
        id: json["id"],
        usersId: json["users_id"],
        invoice: json["invoice"],
        seatNumber: json["seat_number"],
        totalPrice: json["total_price"],
        paymentMethod: json["payment_method"],
        status: json["status"],
        items: List<Item>.from(json["items"].map((x) => Item.fromMap(x))),
    );

    Map<String, dynamic> toMap() => {
        "id": id,
        "users_id": usersId,
        "invoice": invoice,
        "seat_number": seatNumber,
        "total_price": totalPrice,
        "payment_method": paymentMethod,
        "status": status,
        "items": List<dynamic>.from(items.map((x) => x.toMap())),
    };
}

class Item {
    Item({
        this.id,
        this.menusId,
        this.transactionsId,
        this.quantity,
        this.menus,
    });

    final int id;
    final int menusId;
    final int transactionsId;
    final int quantity;
    final Menus menus;

    factory Item.fromJson(String str) => Item.fromMap(json.decode(str));

    String toJson() => json.encode(toMap());

    factory Item.fromMap(Map<String, dynamic> json) => Item(
        id: json["id"],
        menusId: json["menus_id"],
        transactionsId: json["transactions_id"],
        quantity: json["quantity"],
        menus: Menus.fromMap(json["menus"]),
    );

    Map<String, dynamic> toMap() => {
        "id": id,
        "menus_id": menusId,
        "transactions_id": transactionsId,
        "quantity": quantity,
        "menus": menus.toMap(),
    };
}

class Menus {
    Menus({
        this.id,
        this.name,
        this.price,
        this.description,
        this.categoriesId,
    });

    final int id;
    final String name;
    final int price;
    final String description;
    final int categoriesId;

    factory Menus.fromJson(String str) => Menus.fromMap(json.decode(str));

    String toJson() => json.encode(toMap());

    factory Menus.fromMap(Map<String, dynamic> json) => Menus(
        id: json["id"],
        name: json["name"],
        price: json["price"],
        description: json["description"],
        categoriesId: json["categories_id"],
    );

    Map<String, dynamic> toMap() => {
        "id": id,
        "name": name,
        "price": price,
        "description": description,
        "categories_id": categoriesId,
    };
}