(Resolved)(type 'String' is not a subtype of type 'int') - Flutter

Question

This question has already been answered, continue reading if you think you have the same error, the answer was given by the user: Tariqul Islam

since a few days ago there was a flutter update my code shows the following error:

_TypeError (type 'String' is not a subtype of type 'int')

Obviously the application worked perfectly before this update, even after changing from "int" to "String" the same error I get but the other way around:

_TypeError (type 'int' is not a subtype of type 'String')

As much as I change the values ​​the same error still appears to me, it is also clear that the RestApi that I am using did not have any changes.

I get the error when I get to "Chip", after I change it to String I get the same error in "Number", and after I change both the same error appears but the other way around as I indicated above

Here the Json file model:

          class EventoModel {
        String id;
        String nombreEvento;
        List<Participantes> participantes;

        EventoModel({
          this.id,
          this.nombreEvento,
          this.participantes
        });

        factory EventoModel.fromJson(Map<String, dynamic> parsedJson){
          var list = parsedJson['participantes'] as List;
          //print(list.runtimeType);
          List<Participantes> participantesList = list.map((i) => Participantes.fromJson(i)).toList();
          return EventoModel(
            id            : parsedJson ['id'],
            nombreEvento  : parsedJson ['nombreEvento'],
            participantes : participantesList
          );
        }
      }

      class Participantes {
      String uniqueId;
      String apellido;
      int chip;
      String nombre;
      int numero;
      String place;
      String tiempo;

      Participantes({
        this.apellido,
        this.chip,
        this.nombre,
        this.numero,
        this.place,
        this.tiempo,
      });

      factory Participantes.fromJson(Map<String, dynamic> parsedJson) {
        //print(list.runtimeType);
        return Participantes(
          apellido  : parsedJson['Apellido'],
          chip      : parsedJson['Chip'],
          nombre    : parsedJson['Nombre'],
          numero    : parsedJson['Numero'],
          place     : parsedJson['Place'],
          tiempo    : parsedJson['Tiempo'],
        );
      }

      Map<String, dynamic> toJson() {
        return {
          'Apellido'  : apellido,
          'Chip'      : chip,
          'Nombre'    : nombre,
          'Numero'    : numero,
          'Place'     : place,
          'Tiempo'    : tiempo,
        };
      }
    }

This is the Json file Example:

              {
              "nombreEvento" : "Clasico El Colombiano 2020",
              "participantes" : [ {
                "Apellido" : "MARTINEZ GUTIERREZ",
                "Chip" : "739",
                "Nombre" : "JOSE",
                "Numero" : "139",
                "Place" : "1.",
                "Tiempo" : "00:30:12,91"
                }, {
                "Apellido" : "SUAREZ MORERA",
                "Chip" : "707",
                "Nombre" : "DANIEL",
                "Numero" : "107",
                "Place" : "2.",
                "Tiempo" : "02:00:17,54"
                }, {
                "Apellido" : "RODRIGUEZ VARGAS",
                "Chip" : "1686",
                "Nombre" : "JOSE LUIS",
                "Numero" : "274",
                "Place" : "3.",
                "Tiempo" : "02:01:09,09"
                }
              ]
            }

Could someone please help me? : c

Solution 1

If the type of a variable is not explicitly specified, the variable’s type is dynamic. The dynamic keyword can also be used as a type annotation explicitly.

Instead of int you can use dynamic and it will solve the issue.

class Participantes {
  String uniqueId;
  String apellido;
  dynamic chip;
  String nombre;
  dynamic numero;
  String place;
  String tiempo;

  Participantes({
    this.apellido,
    this.chip,
    this.nombre,
    this.numero,
    this.place,
    this.tiempo,
  });

Solution 2

I had like this issue and in this case I did defining type from int to dynamic then it solved. For example: In firebase side I defined number type and I read it with type of dynamic. If you do int in your codes it will warned you "type 'int' is not a subtype of type 'String'" but if you define dynamic it will solve. Code sample is in below.

//class Survey
class Survey {
  String name;
  dynamic vote;  // before it was int type and I have changed
  DocumentReference reference;
  
  Survey.fromMap(Map<String, dynamic> map, {this.reference})

      //datanın var olup olmadığını kontrol et eğer varsa kullan
      : assert(map["name"] != null),
        assert(map["vote"] != null),
        name = map["name"],
        vote = map["vote"];
        
  Anket.fromSnapshot(DocumentSnapshot snapshot)
      : this.fromMap(snapshot.data(), reference: snapshot.reference);
      
}