demo/xinhuaribao/lib/ui/topic/topic_list_page.dart

import 'package:easy_refresh/easy_refresh.dart';
import 'package:flutter/material.dart';
import 'package:flutter_riverpod/flutter_riverpod.dart';
import 'package:flutter_screenutil/flutter_screenutil.dart';
import 'package:go_router/go_router.dart';
import 'package:news_app/ui/topic/topic_item_widget.dart';

import '../../constant/color_res.dart';
import '../../constant/config.dart';
import '../../constant/size_res.dart';
import '../../model/topic_item_model.dart';
import '../../provider/topic_list_provider.dart';
import '../../widget/empty_1_widget.dart';
import '../../widget/my_txt.dart';

class TopicListPage extends ConsumerStatefulWidget {
  final String contentId;

  const TopicListPage({super.key, required this.contentId});

  @override
  ConsumerState<TopicListPage> createState() => _TopicListPageState();
}

final topicListProvider = NotifierProvider<TopicListProvider, TopicItemModel>(
  () => TopicListProvider(),
);

class _TopicListPageState extends ConsumerState<TopicListPage> {
  int _page = 1;
  int _currentTotal = 0;

  @override
  void initState() {
    // TODO: implement initState
    ref
        .read(topicListProvider.notifier)
        .fetchList(page: _page, tid: widget.contentId);
    eventBus.on<String>().listen((event) {
      if (event == "topicCall") {
        _page = 1;
        ref
            .read(topicListProvider.notifier)
            .fetchList(page: _page, tid: widget.contentId);
      }
    });
    super.initState();
  }

  void longTapAction(String contentId) {}

  @override
  Widget build(BuildContext context) {
    final itemData = ref.watch(topicListProvider);
    ref.listen(topicListProvider.select((p) => p.records), (previous, next) {
      _currentTotal = next?.length ?? 0;
    });
    return Scaffold(
      appBar: AppBar(
        scrolledUnderElevation: 0,
        title: myTxt(
          text: '话题列表',
          fontSize: 18.sp,
          fontWeight: FontWeight.bold,
        ),
        centerTitle: true,
      ),
      body: Container(
        // padding: EdgeInsets.symmetric(horizontal: 10.w),
        alignment: Alignment.center,
        color: colorF5F7FD,
        child: EasyRefresh.builder(
          onRefresh: () async {
            _page = 1;
            ref
                .read(topicListProvider.notifier)
                .fetchList(page: _page, tid: widget.contentId);
            return IndicatorResult.success;
          },
          onLoad: () async {
            final newItemData = ref.read(topicListProvider);
            int total = newItemData.total ?? 0;
            if (_currentTotal >= total) {
              return IndicatorResult.noMore;
            } else {
              _page += 1;
              await ref
                  .read(topicListProvider.notifier)
                  .fetchList(page: _page, tid: widget.contentId);
              return IndicatorResult.success;
            }
          },
          childBuilder: (context, py) {
            return (itemData.records ?? []).isEmpty
                ? Empty1widget()
                : ListView.separated(
                  physics: py,
                  padding: EdgeInsets.symmetric(horizontal: horizontalPadding),
                  itemBuilder: (BuildContext context, int index) {
                    return GestureDetector(
                      onTap: () {
                        context.push(
                          "/topic/detail",
                          extra: itemData.records?[index].contentId,
                        );
                      },
                      child: Padding(
                        padding: EdgeInsets.only(
                          // left: horizontalPadding,
                          // right: horizontalPadding,
                          top: horizontalPadding,
                        ),
                        child: TopicItemWidget(
                          longTapAction,
                          item: itemData.records?[index],
                        ),
                      ),
                    );
                  },
                  separatorBuilder: (BuildContext context, int index) {
                    return SizedBox(height: 5.h);
                  },
                  itemCount: itemData.records?.length ?? 0,
                );
          },
        ),
      ),
    );
  }
}