传入新数据时，streamBuilder无法更新

Question

我有一个有状态的小部件和一个简单的块，并且我使用streamBuilder来构建页面。 当我在小部件的build方法中使用bloc时，当输入新数据时，它永远不会更新。 我确定该集团消息已被接收。

不确定要怎么做才能做到这一点？

class ChooseCompanyPage extends StatefulWidget {
  @override
  _ChooseCompanyPageState createState() => _ChooseCompanyPageState();
}

class _ChooseCompanyPageState extends State<ChooseCompanyPage> {
  final bloc = ChooseCompanyBloc();
  List<CompanyModel> companyList;
  @override
  void initState() {
    super.initState();
    bloc.state.listen(
      (event) {
        if (event is JumpToLoginPage) {
          Navigator.of(context).pushReplacementNamed('loginPage');
        }
      },
    );
    bloc.action.add(ChooseCompangeInit());
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
        appBar: AppBar(
          title: Text('Choose your company'),
        ),
        body: _buildBody(context));
  }

  Widget _buildBody(BuildContext context) {
    return StreamBuilder<ChooseCompanyBasicEvent>(
      stream: bloc.state,
      initialData: ChooseCompangeInit(),
      builder: (BuildContext context, snap) {
        final data = snap.data;
        if (data is ChooseCompangeInit) {
          return Center(
            child: CircularProgressIndicator(),
          );
        }
        if (data is GetCompanyData) {
          return RefreshIndicator(
            onRefresh: () {
              bloc.action.add(ChooseCompanyRequest());
            },
            child: ListView.builder(
              itemCount: data.companyList.length,
              itemBuilder: (context, index) {
                final company = data.companyList[index];
                return Column(
                  children: <Widget>[
                    ListTile(
                      title: Text(company.name),
                      onTap: () {
                        support.kiraShowYesOrNoDialog(
                            context: context,
                            title: 'Tip',
                            indicator: 'Choose ${company.name}?',
                            okCallBack: () {
                              bloc.action.add(ChooseACompany(company));
                            });
                      },
                    ),
                    Divider(
                      height: 1,
                    )
                  ],
                );
              },
            ),
          );
        }
      },
    );
  }
}

集团代码就是这样

final Sink<ChooseCompanyBasicEvent> action;



 final Stream<ChooseCompanyBasicEvent> state;

  ChooseCompanyBloc._(this.action, this.state);

  factory ChooseCompanyBloc() {
    final action = PublishSubject<ChooseCompanyBasicEvent>();
    final state = action.switchMap((event) {
      return _generateState(event);
    });
    action.add(ChooseCompangeInit());
    return ChooseCompanyBloc._(action, state);
  }

  void dispose() {
    action.close();
  }

  /// choose Company business logic
  static Stream<ChooseCompanyBasicEvent> _generateState(
      ChooseCompanyBasicEvent event) async* {
    if (event is ChooseCompanyRequest) {
      yield event;
      try {
        final companyList = await _getCompanyList();
        yield GetCompanyData(companyList);
      } catch (e) {
        yield GetDataFailed('');
      }
    }

    if (event is ChooseACompany) {
      final chooseCompany = event.chosenCompany;
      await _saveCompanyID(chooseCompany);
      yield JumpToLoginPage();
    }

    if (event is ChooseCompangeInit) {
      yield event;
      try {
        final companyList = await _getCompanyList();
        if (companyList.length == 0) {
          yield EmtpyData();
        } else {
          yield GetCompanyData(companyList);
        }
      } catch (e) {
        yield GetDataFailed('');
      }
    }
  }

当新数据进入时，streamBuilder不称为构建方法