Using IoC

myip.dart

class MyIp {
  Injector get _injector => Injector.getInjector();
  Client get _client => _injector.get<Client>();

  Future<String> get ipAddress async {
    final apiResult = await _client.get('https://api.ipify.org/?format=json');
    return json.decode(apiResult.body)['ip'];
  }
}