Drop-down list of data allowing to make one or more selections and to search among the data or an identifier

import 'package:drop_down_data/drop_down_data.dart';

List<DataDropDown> listData = [];

@override
void initState() {
  super.initState();
  List<Map<String, dynamic>> listMap = [];
  listMap.add({"id": "1", "name": "agenda"});
  listMap.add({"id": "2", "name": "contact"});
  listData = List<DataDropDown>.from(listMap.map((model) => DataDropDown.fromJson(model)));
}

@override
Widget build(BuildContext context) {
  ThemeData theme = Theme.of(context);
  TextTheme textTheme = theme.textTheme;
  ColorScheme colorScheme = theme.colorScheme;
  return Scaffold(
    appBar: AppBar(
      title: Text(widget.title),
    ),
    body: Center(
      child: Column(
        mainAxisAlignment: MainAxisAlignment.center,
        children: <Widget>[

          Text("Selection", style: textTheme.bodyLarge!.copyWith(color: colorScheme.onSurface),),
          Text("selectionID: $selectionID"),
          Text("selectionValue: $selectionValue"),
          DropDownData(
              tooltip: "show menu",
              title: selectionValue != "" ? " " : "selection",
              value: selectionValue,
              uuidValue: selectionID,
              addFirstEmpty: true,
              viewNumber: true,
              research: false,
              researchCallback: (String val) { setState(() {}); },
              listData: listData,
              selectionCallback: (DataDropDown selection){
                if (kDebugMode) {
                  print(selection);
                  print(selection.id);
                  print(selection.name);
                }
                selectionValue = selection.name ?? "";
                selectionID = selection.id ?? "";
                setState(() { });
              }),
          
        ],
      ),
    ),
  );
}