Bad state: Stream has already been listened to 错误

Question

在我的应用程序中，我有几个流。

这是来自 appsflyer 的示例应用程序。我用它来深度链接我的应用程序。

在第一页我们有 ;

return Scaffold(
  appBar: AppBar(
    title: Column(
      children: <Widget>[
        Text('AppsFlyer SDK example app'),
        FutureBuilder<String>(
            future: _appsflyerSdk.getSDKVersion(),
            builder: (BuildContext context, AsyncSnapshot snapshot) {
              return Text(snapshot.hasData ? snapshot.data : "");
            })
      ],
    ),
  ),
  body: FutureBuilder<dynamic>(
      future: _appsflyerSdk.initSdk(
          registerConversionDataCallback: true,
          registerOnAppOpenAttributionCallback: true),
      builder: (BuildContext context, AsyncSnapshot snapshot) {
        if (snapshot.connectionState == ConnectionState.waiting) {
          return Center(child: CircularProgressIndicator());
        } else {
          if (snapshot.hasData) {
            return HomeContainer(
              onData:
                  _appsflyerSdk.conversionDataStream?.asBroadcastStream(),
              onAttribution: _appsflyerSdk.appOpenAttributionStream
                  ?.asBroadcastStream(),
              trackEvent: logEvent,
            );
          } else {
            return Center(child: Text("Error initializing sdk"));
          }
        }
      }),
);

在 HomeContainer 中

  Stream<Map> onData;
  Stream<Map> onAttribution;
  Future<bool> Function(String, Map) trackEvent;

  HomeContainer({this.onData, this.onAttribution, this.trackEvent});

内部构建；

Column(
            children: <Widget>[

              StreamBuilder<dynamic>(
              stream: widget.onData,
              builder:
                  (BuildContext context, AsyncSnapshot<dynamic> snapshot) {
                return TextBorder(
                  controller: TextEditingController(
                      text: snapshot.hasData
                          ? Utils.formatJson(snapshot.data)
                          : "No conversion data"),
                  labelText: "Conversion Data:",
                );
              }),
              Padding(
                padding: EdgeInsets.only(top: 12.0),
              ),
              StreamBuilder<dynamic>(
              stream: widget.onAttribution,
              builder:
                  (BuildContext context, AsyncSnapshot<dynamic> snapshot) {
                return TextBorder(
                  controller: TextEditingController(
                      text: snapshot.hasData
                          ? _processData(snapshot.data)
                          : "No attribution data"),
                  labelText: "Attribution Data:",
                );
              }),
             
            ],
          ),

我所做的是放置一个按钮来重新加载屏幕，使用 notifyListeners。

当我这样做时，出现以下错误；

Bad state: Stream has already been listened to.

我想，问题可能是因为当我重新加载页面时这些流仍然打开。

但是我不知道怎么关闭它们。

任何人都可以提供一些帮助吗？

Answer 1

StreamBuilder<dynamic>(
  stream: widget.onData?.asBroadcastStream(),

您在 widget.onData 上多次调用 asBroadcastStream()（每次调用构建方法时）。您应该可以使用：

StreamBuilder<dynamic>(
  stream: widget.onData,

如果widget.onData在别处被收听，确保widget.onData本身是一个广播流。

Bad state: Stream has already been listened to 错误

Bad state: Stream has already been listened to error

flutter

streaming

stream-builder

appsflyer