1、FlutterJsonBeanFactory

在Setting->Tools->FlutterJsonBeanFactory里边自定义实体类的后缀，默认是entity

复制json到粘贴板，右键自己要存放实体的目录，可以看到JsonToDartBeanAction

Class Name是实体名字，会默认加上entity
JSON TextJson文本
null-able勾选后所有属性都是可空的?,不勾选都会加上late，延迟初始化

 

执行Make后生成代码目录如下：
models项目自建，存放实体
generated/json是插件生成目录，xx_entity.g.daet是实体类生成的辅助类方法， base是存放基础公共代码

 

后台返回的数据一般是经过一层包装

{
  "code": 200,
  "message": "success",
  "data":{
    "id": "1",
    "name": "qi1",
    "age": 18
  }
}

而重新用插件生成会生成如下代码：

@JsonSerializable()
class ApiResponseEntity {

    int? code;
    String? message;
    ApiResponseData? data;
  
  ApiResponseEntity();

  factory ApiResponseEntity.fromJson(Map<String, dynamic> json) => $ApiResponseEntityFromJson(json);

  Map<String, dynamic> toJson() => $ApiResponseEntityToJson(this);

  @override
  String toString() {
    return jsonEncode(this);
  }
}

@JsonSerializable()
class ApiResponseData {

    String? id;
    String? name;
    int? age;
  
  ApiResponseData();

  factory ApiResponseData.fromJson(Map<String, dynamic> json) => $ApiResponseDataFromJson(json);

  Map<String, dynamic> toJson() => $ApiResponseDataToJson(this);

  @override
  String toString() {
    return jsonEncode(this);
  }
}

要是这样，每一个接口的都有一个ResponseEntity，使用起来不便于统一封装。
所以我们可以把ApiResponseData换成 dynamic，文件底部的ApiResponseData信息也全部删除，再执行Alt+J，这样就会自动清理掉整理json_convert_content.dart和api_response_entity.g.dart中的ApiResponseData痕迹。再把dynamic替换成T,并且去除顶部的@JsonSerializable()，避免下次执行Alt+J，替换掉自己的自定义。

@JsonSerializable()
class ApiResponseEntity<T> {
  late int code;
  late String message;
  late T data;

  ApiResponseEntity();

  factory ApiResponseEntity.fromJson(Map<String, dynamic> json) =>
      $ApiResponseEntityFromJson<T>(json);

  Map<String, dynamic> toJson() => $ApiResponseEntityToJson(this);

  @override
  String toString() {
    return jsonEncode(this);
  }
}

ApiResponseEntity<T> $ApiResponseEntityFromJson<T>(Map<String, dynamic> json) {
  final ApiResponseEntity<T> apiResponseEntity = ApiResponseEntity<T>();
  final int? code = jsonConvert.convert<int>(json['code']);
  if (code != null) {
    apiResponseEntity.code = code;
  }
  final String? message = jsonConvert.convert<String>(json['message']);
  if (message != null) {
    apiResponseEntity.message = message;
  }
  final T data = jsonConvert.convert<dynamic>(json['data']);
  if (data != null) {
    apiResponseEntity.data = data;
  }
  return apiResponseEntity;
}

Map<String, dynamic> $ApiResponseEntityToJson(ApiResponseEntity entity) {
  final Map<String, dynamic> data = <String, dynamic>{};
  data['code'] = entity.code;
  data['message'] = entity.message;
  data['data'] = entity.data;
  return data;
}

并且把api_response_entity.g.dart移除generated目录，因为那个目录会自动删除无用的文件。可以和api_reponse_entity.dart单独存放在一个文件夹当中。

优化后使用

第一次发现，reponse的data是null。因为新的插件在 asT方法没有去调用fromJsonAsT，这个需要我们自加上，否则会失败。

if (_convertFuncMap.containsKey(type)) {
  return _convertFuncMap[type]!(value) as T;
} else {
  return fromJsonAsT<T>(value);
  // throw UnimplementedError('$type unimplemented');
}

  //单实体
  String responseData1 = """
    {
      "code": 200,
      "message": "success",
      "data":{
        "id": 1,
        "name": "qi1",
        "age": 21
      }
    }
    """;

  //List
  String responseData2 = """
    {
      "code": 200,
      "message": "success",
      "data":[
        {
          "id": 1,
          "name": "qi1",
          "age": 21
        },{
          "id": 2,
          "name": "qi2",
          "age": 22
        }
      ]
    }
    """;

//基础数据类型
  String responseData3 = """
    {
      "code": 200,
      "message": "success",
      "data": 18
    }
    """;

  _apiResponseDecode() {
    setState(() {
      response1 = ApiResponseEntity.fromJson(jsonDecode(responseData1));
      response2 = ApiResponseEntity.fromJson(jsonDecode(responseData2));
      response3 = ApiResponseEntity.fromJson(jsonDecode(responseData3));
    });
  }

  _getApiResponseContent() {
    return response1.toString() +
        "\n" +
        response2.toString() +
        "\n" +
        response3.toString();
  }

参考链接：https://juejin.cn/post/7043721908801503269