list_manager 1.0.0

A package which helps you managing lists in flutter. It provide Paging, Filtering, Searching, Filtering + Paging, Searching + Paging, Searching, + Filtering + Paging.

example/lib/main.dart

import 'package:example/PostDataModel.dart';
import 'package:example/postData.dart';
import 'package:flutter/material.dart';
import 'package:list_manager/APIResponse/Result.dart';
import 'package:list_manager/FilterWidget.dart';
import 'package:list_manager/SearchWidget.dart';
import 'package:list_manager/list_manager.dart';
import 'package:list_manager/utils/FilterUtils/FilterController.dart';
import 'package:list_manager/utils/FilterUtils/FilterData.dart';
import 'package:list_manager/utils/PagingUtils/PagingController.dart';
import 'package:list_manager/utils/PagingUtils/PagingHelper.dart';

void main() {
  runApp(const MyApp());
}

class MyApp extends StatelessWidget {
  const MyApp({Key? key}) : super(key: key);

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      debugShowCheckedModeBanner: false,
      title: 'Flutter Demo',
      theme: ThemeData(
        primarySwatch: Colors.blue,
      ),
      home: const MyHomePage(title: 'Flutter Demo Home Page'),
    );
  }
}

class MyHomePage extends StatefulWidget {
  const MyHomePage({Key? key, required this.title}) : super(key: key);
  final String title;

  @override
  State<MyHomePage> createState() => _MyHomePageState();
}

class _MyHomePageState extends State<MyHomePage> {
  late PagingController<PostDataModel> controller;
  late FilterController<PostDataModel> filterController;

  @override
  void initState() {
    super.initState();
    controller = PagingController(
      pagingHelper: PagingHelper.init(error: error, loader: loader()),
      loadData: fetch,
    );
    filterController = FilterController(
      loadFilter: loadFilter,
      pagingController: PagingController(
        pagingHelper: PagingHelper.init(error: filterError, loader: loader()),
        loadData: fetch2,
      ),
      applyFilter: ({selFilters, query, helper}) async {
        return Future.delayed(
          const Duration(seconds: 1),
          () {
            List<PostDataModel> list = [];
            int page = (helper?.page ?? 0);
            for (int i = 10 * (page); i < 10 * (page + 1); i++) {
              var model = PostDataModel.fromMap(filterData["data"][i]);
              list.add(model);
            }
            if (page == 2) {
              return const Failure(reason: "Custom Error Filter wala");
            }
            filterController.pagingController?.setPagingConfig(
              helper?.copyWith(
                    hasNext: true,
                    loadNext: true,
                    page: (page + 1),
                    nextUrl: "nextUrl",
                  ) ??
                  PagingHelper.init(),
            );
            return Success(data: list);
          },
        );
      },
    );
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      body: SafeArea(
        child: Padding(
          padding: const EdgeInsets.symmetric(horizontal: 20, vertical: 20),
          child: Column(
            crossAxisAlignment: CrossAxisAlignment.stretch,
            children: [
              Row(
                children: [
                  Expanded(
                      child: SearchWidget(
                    filterController: filterController,
                    inputBorder: const OutlineInputBorder(),
                  )),
                  IconButton(
                    icon: const Icon(Icons.filter_alt),
                    onPressed: () async {
                      filterController.loadFilters();
                      showFilterBottomSheet();
                    },
                  ),
                ],
              ),
              Expanded(
                child: ListManager<PostDataModel>(
                  itemBuilder:
                      (BuildContext context, PostDataModel data, int index) {
                    return Container(
                      margin: const EdgeInsets.symmetric(vertical: 10),
                      padding: const EdgeInsets.symmetric(
                          vertical: 30, horizontal: 10),
                      decoration: BoxDecoration(
                        color: Colors.grey.shade300,
                        borderRadius: BorderRadius.circular(10),
                      ),
                      child: Text("${data.id}. ${data.title}"),
                    );
                  },
                  pagingController: controller,
                  filterController: filterController,
                  loader: const Center(
                    child: Text(
                      "Loading",
                      style: TextStyle(
                        fontSize: 22,
                        fontWeight: FontWeight.bold,
                      ),
                    ),
                  ),
                  error: (context, error) {
                    return Center(
                      child: Text(
                        "$error => at Page 1 itself",
                        style: const TextStyle(color: Colors.red),
                      ),
                    );
                  },
                ),
              ),
            ],
          ),
        ),
      ),
    );
  }

  Future<Result<List<FilterData>>> loadFilter() async {
    return Future.delayed(const Duration(seconds: 1), () {
      var data = [
        FilterData(
          filterKey: "Sort by Time",
          subFilterOptions: [
            FilterOptionModel(name: "Modified first"),
            FilterOptionModel(name: "Modified last"),
          ],
        ),
        FilterData(filterKey: "Sort by Position", subFilterOptions: [
          FilterOptionModel(name: "Ascending"),
          FilterOptionModel(name: "Descending"),
        ]),
      ];
      return Success(data: data);
    });
  }

  Future<Result<List<PostDataModel>>> fetch(PagingHelper? helper) async {
    return Future.delayed(
      const Duration(seconds: 1),
      () {
        List<PostDataModel> list = [];
        int page = (helper?.page ?? 0);
        for (int i = 10 * (page); i < 10 * (page + 1); i++) {
          var model = PostDataModel.fromMap(postData["data"][i]);
          list.add(model);
        }
        // if (page == 2) return const Failure(reason: "Custom Error");
        controller.setPagingConfig(
          helper?.copyWith(
                hasNext: true,
                loadNext: true,
                page: (page + 1),
                nextUrl: "nextUrl",
              ) ??
              PagingHelper.init(),
        );
        return Success(data: list);
      },
    );
  }

  Future<Result<List<PostDataModel>>> fetch2(PagingHelper? helper) async {
    return Future.delayed(
      const Duration(seconds: 1),
      () {
        List<PostDataModel> list = [];
        int page = (helper?.page ?? 0);
        for (int i = 10 * (page); i < 10 * (page + 1); i++) {
          var model = PostDataModel.fromMap(filterData["data"][i]);
          list.add(model);
        }
        filterController.setPagingConfig(
          helper?.copyWith(
                hasNext: true,
                loadNext: true,
                page: (page + 1),
                nextUrl: "nextUrl",
              ) ??
              PagingHelper.init(),
        );
        return Success(data: list);
      },
    );
  }

  void showFilterBottomSheet() {
    showModalBottomSheet(
      context: context,
      builder: (context) {
        return FilterView(
          controller: filterController,
          onChange: (val) {},
          title: "Filters",
        );
      },
    );
  }

  Widget loader() {
    return const Center(
      child: Text(
        "Loading",
        style: TextStyle(
          color: Colors.blue,
          fontSize: 22,
          fontWeight: FontWeight.bold,
        ),
      ),
    );
  }

  Widget error(context, error) {
    return Center(
      child: Text(
        error,
        style: const TextStyle(
          color: Colors.blue,
          fontSize: 24,
          fontWeight: FontWeight.bold,
        ),
      ),
    );
  }

  Widget filterError(context, error) {
    return Center(
      child: Text(
        "filter: $error",
        style: const TextStyle(
          color: Colors.blue,
          fontSize: 24,
          fontWeight: FontWeight.bold,
        ),
      ),
    );
  }

  @override
  void dispose() {
    super.dispose();
    controller.dispose();
    filterController.dispose();
  }
}