dependencies:
  filter_list: ^0.0.9

import package:filter_list/filter_list.dart';

  List<String> countList = [
    "One",
    "Two",
    "Three",
    "Four",
    "Five",
    "Six",
    "Seven",
    "Eight",
    "Nine",
    "Ten",
    "Eleven",
    "Tweleve",
    "Thirteen",
    "Fourteen",
    "Fifteen",
    "Sixteen",
    "Seventeen",
    "Eighteen",
    "Nineteen",
    "Twenty"
  ];
  List<String>? selectedCountList = [];

  void _openFilterDialog() async {
    await FilterListDialog.display<String>(
      context,
      listData: countList,
      selectedListData: selectedCountList,
      height: 480,
      headlineText: "Select Count",
      searchFieldHintText: "Search Here",
      choiceChipLabel: (item) {
        return item;
      },
      validateSelectedItem: (list, val) {
          return list!.contains(val);
      },
      onItemSearch: (list, text) {
          if (list!.any((element) =>
              element.toLowerCase().contains(text.toLowerCase()))) {
            return list!
                .where((element) =>
                    element.toLowerCase().contains(text.toLowerCase()))
                .toList();
          }
          else{
            return [];
          }
        },
      onApplyButtonClick: (list) {
        if (list != null) {
          setState(() {
            selectedCountList = List.from(list);
          });
        }
        Navigator.pop(context);
      });
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
        appBar: AppBar(
          title: Text(widget.title),
        ),
        floatingActionButton: FloatingActionButton(
          onPressed: _openFilterDialog,
          tooltip: 'Increment',
          child: Icon(Icons.add),
        ),
        body: selectedCountList == null || selectedCountList!.length == 0
            ? Center(
                child: Text('No text selected'),
              )
            : ListView.separated(
                itemBuilder: (context, index) {
                  return ListTile(
                    title: Text(selectedCountList![index]!),
                  );
                },
                separatorBuilder: (context, index) => Divider(),
                itemCount: selectedCountList!.length));
  }

class User {
  final String? name;
  final String? avatar;
  User({this.name, this.avatar});
}



class FilterPage extends StatelessWidget {
  FilterPage({Key? key}) : super(key: key);
  List<User> userList = [
    User(name: "Jon", avatar: ""),
    User(name: "Ethel ", avatar: ""),
    User(name: "Elyse ", avatar: ""),
    User(name: "Nail  ", avatar: ""),
    User(name: "Valarie ", avatar: ""),
    User(name: "Lindsey ", avatar: ""),
    User(name: "Emelyan ", avatar: ""),
    User(name: "Carolina ", avatar: ""),
    User(name: "Catherine ", avatar: ""),
    User(name: "Stepanida  ", avatar: ""),
  ];
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text("Filter List Widget Example "),
      ),
      body: SafeArea(
        child: FilterListWidget<User>(
          listData: userList,
          hideHeaderText: true,
          onApplyButtonClick: (list) {
            if (list != null) {
              print("Selected items count: ${list!.length}");
            }
          },
          label: (item) {
            /// Used to print text on chip
            return item!.name;
          },
          validateSelectedItem: (list, val) {
            ///  identify if item is selected or not
            return list!.contains(val);
          },
          onItemSearch: (list, text) {
            /// When text change in search text field then return list containing that text value
            ///
            ///Check if list has value which matchs to text
            if (list!.any((element) =>
                element.name.toLowerCase().contains(text.toLowerCase()))) {
              /// return list which contains matches
              return list!
                  .where((element) =>
                      element.name.toLowerCase().contains(text.toLowerCase()))
                  .toList();
            }
            else{
              return [];
            }
          },
        ),
      ),
    );
  }
}