flutter-bloc - 卡住 - 一组密封类，其中一些具有其他人没有的字段 - 导致 bloc.state 无法访问缺少的字段

Question

我有这些针对腕尺状态的密封类:

part of 'logged_out_nickname_cubit.dart';

@freezed
abstract class LoggedOutNickNameState with _$LoggedOutNickNameState {
  factory LoggedOutNickNameState.initialised(
          LoggedOutNickNameViewModel vm, String nickNameKey, FormGroup form) =
      _Initialised;
  factory LoggedOutNickNameState.submitted(LoggedOutNickNameViewModel vm) =
      _Submitted;
}

这是肘:

import 'package:bloc/bloc.dart';
import 'package:freezed_annotation/freezed_annotation.dart';
import 'package:reactive_forms/reactive_forms.dart';
import 'package:vepo/domain/user_registration/use-cases/logged_out_use_cases/get_user_field_from_local_use_case.dart';
import 'package:vepo/presentation/modules/logged_out/logged_out_nickname/logged_out_nick_name_view_model.dart';

part 'logged_out_nickname_state.dart';
part 'logged_out_nickname_cubit.freezed.dart';

class LoggedOutNickNameCubit extends Cubit<LoggedOutNickNameState> {
  LoggedOutNickNameCubit(
      this.vm, this.nickNameKey, this.form, this.getUserFieldFromLocalUseCase)
      : super(LoggedOutNickNameState.initialised(vm, nickNameKey, form)) {
    form.control(nickNameKey).value =
        getUserFieldFromLocalUseCase.invoke(nickNameKey);

    form.markAsDirty();
  }

  void submitPressed() => emit(LoggedOutNickNameState.submitted(vm));
  void initialise() =>
      emit(LoggedOutNickNameState.initialised(vm, nickNameKey, form));

  final LoggedOutNickNameViewModel vm;
  final String nickNameKey;
  final FormGroup form;
  final GetUserFieldFromLocalUseCase getUserFieldFromLocalUseCase;
}

问题是在 View 中，我尝试访问 loggedOutNicknameCubit.state.form 并且由于该表单在其中一个密封类中不存在，因此无法识别为在 bloc 中状态，在我看来不能使用:

The getter 'form' isn't defined for the type 'LoggedOutNickNameState'

修复方法是将字段添加到所有不使用它的密封类，如下所示:

factory LoggedOutNickNameState.submitted(LoggedOutNickNameViewModel vm,
      {@nullable @Default(null) FormGroup form}) = _Submitted;

有没有办法消除不涉及将字段作为 null 添加到不需要它的密封类的错误？

Answer 1

您可以使用强制转换来获取这些变量

(loggedOutNicknameCubit.state as _Initialised).form