Flutter 列表刷新快速集成方案 工具类

如果你项目中有大量的列表刷新功能，上拉加载更多需求，你可以尝试这个方案，只需要实例化一个NFTrefreshListController子类，实现对应接口，就可以快速接入列表刷新需求。
整个列表的需求相当于是独立的，整体相当于已隔离，颗粒度相当满意。

依赖 easy_refresh, 你也可以替换其他刷新包。

示例代码

class HomeTabSocial extends StatefulWidget {
  const HomeTabSocial({Key? key}) : super(key: key);

  @override
  State<HomeTabSocial> createState() => _HomeTabSocialState();
}

class _HomeTabSocialState extends State<HomeTabSocial>
    {

final socialController = HomeTabSocialController()..onLoad();

@override
  Widget build(BuildContext context) {
    return Scaffold(
      body: NFTrefreshList(
        controller: socialController,
        itemBuilder: (context, index) => SocialFeedListTile(
          item: socialController.data[index],
        ),
      ),
    );
  }


class HomeTabSocialController extends NFTrefreshListController<SocailFeedItem> {
  @override
  Future<List<SocailFeedItem>> fetchData(int page) async {
    var result = await MyRequest.post('api/v1/newList', data: {
      'member_id': '[memberId]', 
      'page': page,
      'page_size': pageSize,
    });
    var data = result.data['data'] as Map;
    var list = (data['list'] as List)
        .map((e) => SocailFeedItem.from(e, data))
        .toList();
    return list;
  }

  @override
  int get pageSize => 3;

  @override
  bool get hasFooter => true;

  @override
  bool get hasHeader => true;
}

源码

import 'dart:async';
import 'package:flutter/cupertino.dart';
import 'package:flutter_easyrefresh/easy_refresh.dart';
import 'package:get/get.dart';


class NFTrefreshList extends StatelessWidget {
  final NFTrefreshListController controller;
  final NullableIndexedWidgetBuilder itemBuilder;
  final IndexedWidgetBuilder? separatorBuilder;

  const NFTrefreshList({
    Key? key,
    required this.controller,
    required this.itemBuilder,
    this.separatorBuilder,
  }) : super(key: key);

  @override
  Widget build(BuildContext context) {
    return StreamBuilder<List>(
      stream: controller.stream,
      initialData: controller.data,
      builder: (context, snap) {
        if (snap.hasData) {
          return EasyRefresh(
            header: ClassicalHeader(),
            footer: ClassicalFooter(),
            controller: controller.easyRefresh,
            onLoad: controller.onLoad,
            onRefresh: controller.onRefresh,
            child: ListView.separated(
              itemCount: snap.data!.length,
              itemBuilder: itemBuilder,
              separatorBuilder:
                  separatorBuilder ?? (_, __) => const SizedBox.shrink(),
            ),
          );
        } else {
          return const CupertinoActivityIndicator();
        }
      },
    );
  }
}

abstract class NFTrefreshListController<T> {
  bool get hasHeader;
  bool get hasFooter;
  NFTrefreshListController();

  final EasyRefreshController easyRefresh = EasyRefreshController();
  final List<T> data = [];

  int get pageSize;
  int page = 1;

  final _controller = StreamController<List>.broadcast();
  Stream<List> get stream => _controller.stream;

  Future<void> onLoad() async {
    var list = await fetchData(page);
    if (list.isNotEmpty) {
      data.addAll(list);
      page += 1;
      _controller.add(data);
    } else {
      easyRefresh.finishLoad(success: true, noMore: true);
    }
    return;
  }

  Future<void> onRefresh() async {
    easyRefresh.resetLoadState();
    page = 1;
    var list = await fetchData(page);
    data.clear();
    data.addAll(list);
    page += 1;
    _controller.add(data);
    return;
  }

  Future<List<T>> fetchData(int page);
}