mobile-app/lib/presentation/screens/plot/sc_plot.dart

import 'package:farm_tpf/data/repository/repository.dart';
import 'package:farm_tpf/presentation/custom_widgets/bottom_loader.dart';
import 'package:farm_tpf/presentation/custom_widgets/loading_list_page.dart';
import 'package:farm_tpf/presentation/screens/plot/widget_search.dart';
import 'package:farm_tpf/presentation/screens/plot_detail/sc_plot_detail.dart';
import 'package:farm_tpf/utils/pref.dart';
import 'package:flutter/material.dart';
import 'package:flutter_bloc/flutter_bloc.dart';
import 'package:farm_tpf/utils/const_string.dart';

import 'bloc/plot_bloc.dart';
import 'widgets/item_plot.dart';

class PlotListScreen extends StatefulWidget {
  @override
  _PlotListScreenState createState() => _PlotListScreenState();
}

class _PlotListScreenState extends State<PlotListScreen> {
  var pref = LocalPref();
  var token;
  var client;
  String pushkey = "";
  String currentFullName = "";

  @override
  void initState() {
    super.initState();
  }

  @override
  Widget build(BuildContext context) {
    return BlocProvider(
      create: (context) => PlotBloc(repository: Repository())..add(DataFetched()),
      child: HoldInfinityWidget(),
    );
  }
}

class HoldInfinityWidget extends StatelessWidget {
  final GlobalKey<ScaffoldState> _scaffoldKey = new GlobalKey<ScaffoldState>();
  @override
  Widget build(BuildContext context) {
    return Scaffold(backgroundColor: Colors.white, key: _scaffoldKey, body: SafeArea(child: InfinityView()));
  }
}

class InfinityView extends StatefulWidget {
  @override
  _InfinityViewState createState() => _InfinityViewState();
}

class _InfinityViewState extends State<InfinityView> {
  final _scrollController = ScrollController();
  final _scrollThreshold = 250.0;
  PlotBloc? _plotBloc;

  @override
  void initState() {
    _scrollController.addListener(() {
      final maxScroll = _scrollController.position.maxScrollExtent;
      final currentScroll = _scrollController.position.pixels;
      if (maxScroll - currentScroll < _scrollThreshold) {
        _plotBloc?.add(DataFetched());
      }
    });
    _plotBloc = BlocProvider.of<PlotBloc>(context);
    super.initState();
  }

  @override
  Widget build(BuildContext context) {
    return Column(
      crossAxisAlignment: CrossAxisAlignment.start,
      children: <Widget>[
        SizedBox(
          height: 8,
        ),
        Container(
          padding: EdgeInsets.all(8),
          color: Colors.white,
          child: Text(
            'Danh sách lô trồng',
            style: TextStyle(fontWeight: FontWeight.w500, fontSize: 22),
          ),
        ),
        WidgetSearch(
          searchController: TextEditingController(),
          onPressed: (value) {
            FocusScope.of(context).requestFocus(FocusNode());
            BlocProvider.of<PlotBloc>(context).add(OnSearch(searchString: value));
          },
        ),
        Expanded(child: BlocBuilder<PlotBloc, PlotState>(
          builder: (context, state) {
            if (state is PlotFailure) {
              return Center(child: Text(state.errorString));
            }
            if (state is PlotSuccess) {
              if ((state.items ?? []).isEmpty) {
                return Center(child: Text(label_list_empty));
              }
              return RefreshIndicator(
                child: ListView.builder(
                  physics: AlwaysScrollableScrollPhysics(),
                  itemBuilder: (BuildContext context, int index) {
                    return index >= (state.items ?? []).length
                        ? BottomLoader()
                        : ItemPlot(
                            item: state.items?[index],
                            onPressed: () {
                              Navigator.push(
                                context,
                                MaterialPageRoute(
                                  builder: (BuildContext context) => PlotDetailScreen(
                                    cropId: state.items?[index].id ?? -1,
                                    initialIndex: 0,
                                    cropType: state.items?[index].tbCropTypeId ?? -1,
                                  ),
                                ),
                              );
                            },
                          );
                  },
                  itemCount: (state.hasReachedMax ?? false) ? (state.items ?? []).length : (state.items ?? []).length + 1,
                  controller: _scrollController,
                ),
                onRefresh: () async {
                  _plotBloc?.add(OnRefresh());
                },
              );
            }
            return Center(
              child: LoadingListPage(),
            );
          },
        ))
      ],
    );
  }

  @override
  void dispose() {
    _scrollController.dispose();
    super.dispose();
  }
}