aman-satu-flutter/lib/views/dictionaries/goods/goods_view.dart

import 'dart:async';

import 'package:flutter/material.dart';
import 'package:flutter_svg/svg.dart';
import 'package:infinite_scroll_pagination/infinite_scroll_pagination.dart';
import 'package:satu/core/models/dictionary/good/good_response_entity.dart';
import 'package:satu/core/services/dictionary_service.dart';
import 'package:satu/core/services/navigator_service.dart';
import 'package:satu/core/utils/locator.dart';
import 'package:satu/routes/route_names.dart';
import 'package:satu/shared/app_colors.dart';
import 'package:satu/views/dictionaries/component/dictionary_list_tile.dart';
import 'package:satu/widgets/bar/products_app_bar.dart';
import 'package:satu/widgets/bar/products_title_bar.dart';
import 'package:satu/widgets/fields/input_field.dart';
import 'package:satu/widgets/ui/product_title_widget.dart';

class GoodsDictionaryView extends StatefulWidget {
  @override
  _GoodsDictionaryViewState createState() => _GoodsDictionaryViewState();
}

class _GoodsDictionaryViewState extends State<GoodsDictionaryView> {
  final DictionaryService _dictionaryService = locator<DictionaryService>();
  final NavigatorService _navigatorService = locator<NavigatorService>();
  late TextEditingController _searchTextController;
  final FocusNode _searchFocusNode = FocusNode();
  static const _pageSize = 20;
  String query = '';
  Timer? _debounce;

  final PagingController<int, GoodResponseEntity> _pagingController =
      PagingController(firstPageKey: 1);

  @override
  void initState() {
    _searchTextController = TextEditingController();
    _searchTextController.addListener(() {
      setState(() {
        query = _searchTextController.text;
      });
      if (_debounce?.isActive ?? false) _debounce?.cancel();
      _debounce = Timer(const Duration(milliseconds: 500), () {
        _pagingController.refresh();
      });
    });
    _pagingController.addPageRequestListener((pageKey) {
      _fetchData(pageKey, _pageSize, query);
    });
    super.initState();
  }

  @override
  void dispose() {
    _debounce?.cancel();
    _pagingController.dispose();
    _searchTextController.dispose();
    _searchFocusNode.dispose();
    super.dispose();
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: ProductsAppBar(
        title: 'Товары',
        drawerShow: true,
        actions: [
          ClipRRect(
            borderRadius: BorderRadius.circular(90),
            child: Material(
              color: Colors.transparent,
              child: InkWell(
                onTap: () {},
                child: Padding(
                  padding: const EdgeInsets.all(16.0),
                  child: SvgPicture.asset(
                    'assets/images/svg/options.svg',
                    height: 20,
                    width: 20,
                    color: textColor,
                  ),
                ),
              ),
            ),
          ),
        ],
      ),
      body: Column(
        children: [
          InputField(
            placeholder: 'Поиск по наименованию товара или штрих-код',
            search: true,
            controller: _searchTextController,
            fieldFocusNode: _searchFocusNode,
          ),
          const ProductsTitleBarBar(title: 'Список товаров'),
          Expanded(
            child: PagedListView<int, GoodResponseEntity>.separated(
              physics: const BouncingScrollPhysics(),
              separatorBuilder: (BuildContext context, int index) {
                return const Divider(
                  height: 1.0,
                  color: disableColor,
                );
              },
              pagingController: _pagingController,
              builderDelegate: PagedChildBuilderDelegate<GoodResponseEntity>(
                itemBuilder:
                    (BuildContext context, GoodResponseEntity good, int index) {
                  return DictionaryTile(
                    key: Key('good_${good.id}'),
                    onPress: () async {
                      final dynamic result = await _navigatorService
                          .push(goodsEditRoute, arguments: good);
                      if (result != null && true == (result as bool)) {
                        _pagingController.refresh();
                      }
                    },
                    child: ProductTitleWidget(
                      name: good.name,
                      categoryName: good.categoryName,
                      ean: good.ean13,
                    ),
                  );
                },
              ),
            ),
          )
        ],
      ),
      floatingActionButton: FloatingActionButton(
        elevation: 2,
        onPressed: () async {
          final dynamic result = await _navigatorService.push(goodsEditRoute,
              arguments: GoodResponseEntity());
          if (result != null && true == (result as bool)) {
            _pagingController.refresh();
          }
        },
        child: const Icon(
          Icons.add_rounded,
          size: 34.0,
          color: whiteColor,
        ),
      ),
    );
  }

  void reset() {
    _searchTextController.clear();
  }

  Future<void> _fetchData(int pageKey, int perPage, String? query) async {
    final List<GoodResponseEntity> newItems = await _dictionaryService.getGoods(
        page: pageKey,
        filter: {'col': 'name', 'action': 'like', 'val': query ?? ''},
        perpage: perPage);

    final isLastPage = newItems.length < _pageSize;
    if (isLastPage) {
      _pagingController.appendLastPage(newItems);
    } else {
      final nextPageKey = pageKey + 1;
      _pagingController.appendPage(newItems, nextPageKey);
    }
  }
}