Flutter-multi-level-dropdown-04.dart

import 'package:states_lga/state_model.dart';

class Repository {
  List<Map> getAll() => _nigeria;

getLocalByState(String state) => _nigeria
      .map((map) => StateModel.fromJson(map))
      .where((item) => item.state == state)
      .map((item) => item.lgas)
      .expand((i) => i)
      .toList();


  List<String> getStates() => _nigeria
      .map((map) => StateModel.fromJson(map))
      .map((item) => item.state)
      .toList();
  
   List _nigeria = [
     
     ...