分页对象通用page的bean编写

问题描述

• 我们做分页请求的时候，后台返回的数据格式类似这种

  
  image.png

后端采用了泛型的方式。

• 之前flutter解析的时候，我们需要对这个进行序列化

  
  image.png

• 如果仅仅有一个接口还好，但是如果有多个分页的接口，每一个接口都需要编写两个bean文件，导致文件过多，而且做了很多重复工作

思路

观察原来的bean类，核心在MineWalletPageDtoSerializer

// GENERATED CODE - DO NOT MODIFY BY HAND

part of 'mine_wallet_month_pay_page_dto.dart';

// **************************************************************************
// JaguarSerializerGenerator
// **************************************************************************

abstract class _$MineWalletPageDtoSerializer
    implements Serializer<MineWalletPageDto> {
  Serializer<MinePayRecordDto> __minePayRecordDtoSerializer;
  Serializer<MinePayRecordDto> get _minePayRecordDtoSerializer =>
      __minePayRecordDtoSerializer ??= MinePayRecordDtoSerializer();
  @override
  Map<String, dynamic> toMap(MineWalletPageDto model) {
    if (model == null) return null;
    Map<String, dynamic> ret = <String, dynamic>{};
    setMapValue(ret, 'currentPage', model.currentPage);
    setMapValue(ret, 'pageSize', model.pageSize);
    setMapValue(ret, 'totalRow', model.totalRow);
    setMapValue(ret, 'totalPage', model.totalPage);
    setMapValue(
        ret,
        'result',
        codeIterable(
            model.result,
            (val) =>
                _minePayRecordDtoSerializer.toMap(val as MinePayRecordDto)));
    return ret;
  }

  @override
  MineWalletPageDto fromMap(Map map) {
    if (map == null) return null;
    final obj = MineWalletPageDto();
    obj.currentPage = map['currentPage'] as int;
    obj.pageSize = map['pageSize'] as int;
    obj.totalRow = map['totalRow'] as int;
    obj.totalPage = map['totalPage'] as int;
    obj.result = codeIterable<MinePayRecordDto>(map['result'] as Iterable,
        (val) => _minePayRecordDtoSerializer.fromMap(val as Map));
    return obj;
  }
}

需要每次把需要的reult中的列表类型定好，传进去，
可以考虑通过泛型的方式，把类型作为参数传进去，编写一个通用的pageDto

解决方案

所以需要一个可以适配多中page的通用pageDto实现，考虑可以通过泛型的方式，把类型作为参数传进去

import 'package:jaguar_serializer/jaguar_serializer.dart';
part 'common_page_dto.jser.dart';


class CommonPageDto<T> {
  int currentPage;
  int pageSize;
  int totalRow;
  int totalPage;
  List<T> result;
  CommonPageDto({this.currentPage, this.pageSize, this.totalRow, this.totalPage, this.result});

 
}

part of 'common_page_dto.dart';

class CommonPageDtoSerializer<T> {
  Serializer<T> recordDtoSerializer;
  CommonPageDtoSerializer({this.recordDtoSerializer});
  Map<String, dynamic> toMap(CommonPageDto model) {
    if (model == null) return null;
    Map<String, dynamic> ret = <String, dynamic>{};
    setMapValue(ret, 'currentPage', model.currentPage);
    setMapValue(ret, 'pageSize', model.pageSize);
    setMapValue(ret, 'totalRow', model.totalRow);
    setMapValue(ret, 'totalPage', model.totalPage);
    setMapValue(ret, 'result',
        codeIterable(model.result, (val) => this.recordDtoSerializer.toMap(val as T)));
    return ret;
  }
  CommonPageDto fromMap(Map map) {
    if (map == null) return null;
    final obj = CommonPageDto();
    obj.currentPage = map['currentPage'] as int;
    obj.pageSize = map['pageSize'] as int;
    obj.totalRow = map['totalRow'] as int;
    obj.totalPage = map['totalPage'] as int;
    obj.result = codeIterable<T>(
        map['result'] as Iterable, (val) => this.recordDtoSerializer.fromMap(val as Map));
    return obj;
  }
}

使用方法

CommonPageDto<MinePayRecordDto> pageDto = CommonPageDtoSerializer(recordDtoSerializer: MinePayRecordDtoSerializer()).fromMap(res.data);
 

之前调用

MineWalletPageDto pageDto = MineWalletPageDtoSerializer().fromMap(res.data);

优点

1. 两个文件实现多个接口类型的分页数据
2. 一行代码实现序列化