如何将dio的响应数据分配给飞镖对象？

问题描述

我正在尝试使用dio来获取API的用户。但是，当我尝试将请求转换为dart用户列表时，它不起作用。

我的编码器和解码器类：，该类是从在线json解码器站点中生成的。

List<User> userListFromJson(String str) =>
    List<User>.from(json.decode(str).map((x) => User.fromJson(x)));

User userFromJson(String str) => User.fromJson(json.decode(str));

String userToJson(User data) => json.encode(data.toJson());

class User {
  User({
    this.url,this.id,this.image,this.username,this.nid,this.email,this.password,this.firstName,this.lastName,this.isActive,this.isStaff,this.isAuthority,this.isSpecialist,this.isGeneralUser,});

  String url;
  int id;
  String image;
  String username;
  String nid;
  String email;
  String password;
  dynamic firstName;
  dynamic lastName;
  bool isActive;
  bool isStaff;
  bool isAuthority;
  bool isSpecialist;
  bool isGeneralUser;

  factory User.fromJson(Map<String,dynamic> json) => User(
        url: json["url"] == null ? null : json["url"],id: json["id"] == null ? null : json["id"],image: json["image"] == null ? null : json["image"],username: json["username"] == null ? null : json["username"],nid: json["nid"] == null ? null : json["nid"],email: json["email"] == null ? null : json["email"],password: json["password"] == null ? null : json["password"],firstName: json["first_name"],lastName: json["last_name"],isActive: json["is_active"],isStaff: json["is_staff"],isAuthority: json["is_authority"],isSpecialist: json["is_specialist"],isGeneralUser: json["is_general_user"],);

  Map<String,dynamic> toJson() => {
        "url": url == null ? null : url,"id": id == null ? null : id,"image": image == null ? null : image,"username": username == null ? null : username,"nid": nid == null ? null : nid,"email": email == null ? null : email,"first_name": firstName,"last_name": lastName,"is_active": isActive == false ? false : isActive,"is_staff": isStaff == false ? false : isStaff,"is_authority": isAuthority == false ? false : isAuthority,"is_specialist": isSpecialist == false ? false : isSpecialist,"is_general_user": isGeneralUser == false ? false : isGeneralUser,};
}

我的Api请求类，它返回dio的响应。

  Future<dio.Response> getAllUsers() async {
    return await _dio.get(
      '$baseUrl/user/list',options: dio.Options(
        contentType: dio.Headers.jsonContentType,headers: requestHeader,),);
  }

提供商的代码，响应将在其中转换和存储以供应用使用。

  Future<bool> fetchUsersList() async {
    var resp = await ApIService().getAllUsers();
    if (resp.statusCode == 200) {
      List rawJson = resp.data;
      var users = rawJson.map((e) => userFromJson(e)).toList();
      _setUsersList(users);
      return true;
    } else {
      _setMessage(jsonDecode(resp.data)['detail']);
      _setStatusCode(resp.statusCode);
      return false;
    }
  }

代码运行时显示如下错误：

[ERROR：flutter / lib / ui / ui_dart_state.cc（157）]未处理的异常：类型'_InternalLinkedHashMap '不是类型'String'的子类型

解决方法

class User {
  String url;
  int id;
  String image;
  String username;
  String nid;
  String email;
  String password;
  dynamic firstName;
  dynamic lastName;
  bool isActive;
  bool isStaff;
  bool isAuthority;
  bool isSpecialist;
  bool isGeneralUser;
  User({
    this.url,this.id,this.image,this.username,this.nid,this.email,this.password,this.firstName,this.lastName,this.isActive,this.isStaff,this.isAuthority,this.isSpecialist,this.isGeneralUser,});
  
  Map<String,dynamic> toMap() {
    return {
      'url': url,'id': id,'image': image,'username': username,'nid': nid,'email': email,'password': password,'firstName': firstName,'lastName': lastName,'isActive': isActive,'isStaff': isStaff,'isAuthority': isAuthority,'isSpecialist': isSpecialist,'isGeneralUser': isGeneralUser,};
  }

  factory User.fromMap(Map<String,dynamic> map) {
    if (map == null) return null;
  
    return User(
      url: map['url'],id: map['id'],image: map['image'],username: map['username'],nid: map['nid'],email: map['email'],password: map['password'],firstName: map['firstName'],lastName: map['lastName'],isActive: map['isActive'],isStaff: map['isStaff'],isAuthority: map['isAuthority'],isSpecialist: map['isSpecialist'],isGeneralUser: map['isGeneralUser'],);
  }

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

  factory User.fromJson(String source) => User.fromMap(json.decode(source));

}

  Future<bool> fetchUsersList() async {
   List<User> _setUsersList = [];

    var resp = await ApIService().getAllUsers();
    if (resp.statusCode == 200) {
      resp.data.forEach((data) {
          User user = User.fromMap(data);
          _setUsersList.add(user);
        });
      return true;
    } else {
      _setStatusCode(resp.statusCode);
      return false;
    }
  }