TheAlphamerc/filterlist

import 'package:filter_list/filter_list.dart';

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

List<User> userList = [
 User(name: "Jon", avatar: ""),
  User(name: "Lindsey ", avatar: ""),
  User(name: "Valarie ", avatar: ""),
  User(name: "Elyse ", avatar: ""),
  User(name: "Ethel ", avatar: ""),
  User(name: "Emelyan ", avatar: ""),
  User(name: "Catherine ", avatar: ""),
  User(name: "Stepanida  ", avatar: ""),
  User(name: "Carolina ", avatar: ""),
  User(name: "Nail  ", avatar: ""),
  User(name: "Kamil ", avatar: ""),
  User(name: "Mariana ", avatar: ""),
  User(name: "Katerina ", avatar: ""),
];

  void openFilterDialog() async {
    await FilterListDialog.display<User>(
      context,
      listData: userList,
      selectedListData: selectedUserList,
      choiceChipLabel: (user) => user!.name,
      validateSelectedItem: (list, val) => list!.contains(val),
      onItemSearch: (user, query) {
        return user.name!.toLowerCase().contains(query.toLowerCase());
      },
      onApplyButtonClick: (list) {
        setState(() {
          selectedUserList = List.from(list!);
        });
        Navigator.pop(context);
      },
    );
  }

@override
  Widget build(BuildContext context) {
    return Scaffold(
      floatingActionButton: FloatingActionButton(
        onPressed: openFilterDialog,
        child: Icon(Icons.add),
      ),
      body: selectedUserList == null || selectedUserList!.length == 0
          ? Center(child: Text('No user selected'))
          : ListView.builder(
              itemBuilder: (context, index) {
                return ListTile(
                  title: Text(selectedUserList![index].name!),
                );
              },
              itemCount: selectedUserList!.length,
            ),
    );
  }

class FilterPage extends StatelessWidget {
  const FilterPage({Key? key, this.selectedUserList})
      : super(key: key);
  final List<User>? selectedUserList;
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      body: FilterListWidget<User>(
        listData: userList,
        selectedListData: selectedUserList,
        onApplyButtonClick: (list) {
          // do something with list ..
        },
        choiceChipLabel: (item) {
          /// Used to display text on chip
          return item!.name;
        },
        validateSelectedItem: (list, val) {
          ///  identify if item is selected or not
          return list!.contains(val);
        },
        onItemSearch: (user, query) {
          /// When search query change in search bar then this method will be called
          ///
          /// Check if items contains query
          return user.name!.toLowerCase().contains(query.toLowerCase());
        },
      ),
    );
  }
}

 void openFilterDelegate() async {
   await FilterListDelegate.open<User>(
      context: context,
      list: userList,
      onItemSearch: (user, query) {
        return user.name!.toLowerCase().contains(query.toLowerCase());
      },
      tileLabel: (user) => user!.name,
      emptySearchChild: Center(child: Text('No user found')),
      searchFieldHint: 'Search Here..',
      onApplyButtonClick: (list) {
        // Do something with selected list
      },
    );
  }