Dart Flutter 以编程方式触发 FutureBuilder

假设我有这样的东西:

return FutureBuilder(
  future: _loadingDeals,
  builder: (BuildContext context, AsyncSnapshot snapshot) {
    return RefreshIndicator(
      onRefresh: _handleRefresh,
        ...
    )
  }
 )

在_handleRefresh方法中，我希望以编程方式触发FutureBuilder的重新运行.

有这样的事吗？

用例:

当用户取下refreshIndicator时，_handleRefresh只需让FutureBuilder自己重新运行.

Edit:

完整的代码段首尾相连，没有刷新部分.我已经改用了StreamBuilder，refreshIndicator部分如何适应所有这些？

class DealList extends StatefulWidget {
  @override
  State<StatefulWidget> createState() => new _DealList();
}

class _DealList extends State<DealList> with AutomaticKeepAliveClientMixin {
  // prevents refreshing of tab when switch to
  // Why? https://stackoverflow.com/q/51224420/1757321
  bool get wantKeepAlive => true; 

  final RestDatasource api = new RestDatasource();
  String token;
  StreamController _dealsController;

  @override
  void initState() {
    super.initState();
    _dealsController = new StreamController();
    _loadingDeals();
  }

  _loadingDeals() async {
    SharedPreferences prefs = await SharedPreferences.getInstance();

    this.token = prefs.getString('token');

    final res =
        this.api.checkInterests(this.token).then((interestResponse) async {
      _dealsController.add(interestResponse);
      return interestResponse;
    });
    return res;
  }

  _handleRefresh(data) async {
    SharedPreferences prefs = await SharedPreferences.getInstance();

    final token = prefs.getString('token');
    await this.api.checkInterests(token).then((interestResponse) {
      _dealsController.add(interestResponse);
    });
    return null;
  }

  @override
  Widget build(BuildContext context) {
    super.build(context); // <-- this is with the wantKeepAlive thing
    return StreamBuilder(
      stream: _dealsController.stream,
      builder: (BuildContext context, AsyncSnapshot snapshot) {

        if (snapshot.hasError) {
          ...
        }

        if (snapshot.connectionState != ConnectionState.done) {
          return Center(
            child: CircularProgressIndicator(),
          );
        }

        if (!snapshot.hasData &&
            snapshot.connectionState == ConnectionState.done) {
          return Text('No deals');
        }

        if (snapshot.hasData) {
          return ListView.builder(
                physics: const AlwaysScrollableScrollPhysics(),
                itemCount: snapshot.data['deals'].length,
                itemBuilder: (context, index) {
                  final Map deal = snapshot.data['deals'][index];
                  return ListTile(
                      onTap: () {
                        Navigator.push(
                          context,
                          MaterialPageRoute(
                            builder: (context) => DealsDetailPage(
                                  dealDetail: deal,
                                ),
                          ),
                        );
                      },
                      title: Text(deal['name']),
                      subtitle: Text(deal['expires']),
                    );
                },
              ),
        }
      },
    );
  }
}