Hello i am trying to save my request into my List but it says that Unhandled Exception: type 'String' is not a subtype of type 'int' of 'index'.

Hello i am trying to save my request into my List but it says that Unhandled Exception: type 'String' is not a subtype of type 'int' of 'index'.

Here is my Class:

class Evsebill {
  final String serial;
  final double value;
  final double vat;
  final double total;
  final int energy;
 const Evsebill({
    required this.serial,
    required this.value,
    required this.vat,
    required this.total,
    required this.energy
  });
  factory Evsebill.fromJson(Map<String, dynamic> json) {
    return Evsebill(
      serial: json['serial'] as String,
      value: json['value']as double,
      vat: json['vat']as double,
      total: json['total']as double,
      energy: json['energy']as int,
    );
  }
}

Here is my request:

List<Evsebill> parseBills(String responseBody) {
    final parsed = jsonDecode(responseBody)["results"]["cardBillsTotal"].cast<Map<String, dynamic>>();

    return parsed.map<Evsebill>((json) => Evsebill.fromJson(json)).toList();
  }

Future<List<Evsebill>> fetch() async {
    String? token = await this.storage.read(key: "token");
    Map<String, String> headers = {
      "Content-Type": "application/json",
      "Accept": "application/json",
      "Authorization": "Bearer "   (token ?? ""),
    };
    final response = await http.get(Uri.parse(
        this.serverIP   ':'   this.serverPort  
            '/user/contractedChargeTransactionsList?page=1&limit=10&year=eq:2022'),
        headers: headers);
    if (response.statusCode == 200) {
      setState(() {
        print(response.body);
        cardBills = jsonDecode(response.body)["results"]["cardBillsTotal"] as List;
        var result = cardBills.map((e) => Evsebill.fromJson(e)).toList();
      });
      return cardBills.map((e) => Evsebill.fromJson(e)).toList();
    }
    else{
      throw Exception('Failed to load Bills');
    }
  }

here is my print(response.body);

I/flutter (19587): {"results":[{"firstName":"Θωμάς","lastName":"Παπαϊωάννου","userID":238,"month":5,"year":2022,"cardBillsTotal":[{"serial":"884221337251","value":1.0450,"vat":0.2508,"total":1.2958,"energy":0}]},{"firstName":"Θωμάς","lastName":"Παπαϊωάννου","userID":238,"month":6,"year":2022,"cardBillsTotal":[{"serial":"884221337251","value":3.4034,"vat":0.8168,"total":4.2202,"energy":0}]},{"firstName":"Θωμάς","lastName":"Παπαϊωάννου","userID":238,"month":7,"year":2022,"cardBillsTotal":[{"serial":"884221337251","value":2.0900,"vat":0.5016,"total":2.5916,"energy":0}]},{"firstName":"Θωμάς","lastName":"Παπαϊωάννου","userID":238,"month":5,"year":2022,"cardBillsTotal":[{"serial":"941368618045","value":2.2884,"vat":0.5492,"total":2.8376,"energy":0}]},{"firstName":"Θωμάς","lastName":"Παπαϊωάννου","

CodePudding user response：

You should iterate your http reponse, because it is a list and at first you should access each element. So instead of these,

cardBills = jsonDecode(response.body)["results"]["cardBillsTotal"] as List;
        //cardBillsTotal = jsonDecode(response.body)["cardBillsTotal"] as List;
        month = jsonDecode(response.body)['month'];
        userid = jsonDecode(response.body)['userID'];

you should have something like this:

final response = jsonDecode(response.body)["results"];
(response as List<dynamic>).forEach((e) {

        month = e['month'];
        userid = e['userID'];

        //and so on
        })
        .toList()

I think you get the main idea.