requiredFieldValidator property

StreamTransformer<String, String> requiredFieldValidator
getter/setter pair

Implementation

StreamTransformer<String, String> requiredFieldValidator =
    StreamTransformer<String, String>.fromHandlers(
      handleData: (String txt, EventSink<String> sink) {
        final String? error = RequiredFieldValidator().validate(txt);
        error != null ? sink.addError(error) : sink.add(txt);
      },
    );