Flutter, “Stream has already been listened to” error in GridView

0

What I'm doing is to fetch cartoon list and show by GridView. Below code is fetching data

Future<void> _getWebtoonData() async {

    var response;

    if(_daysReceivedResponse[_pressedButtonDayIndex]){

      response = _daysResponse[_pressedButtonDayIndex];

    } else {

      response= await http.get('https://comic.naver.com/webtoon/weekdayList.nhn?week='+_currentWebtoonAddress);

      _daysReceivedResponse[_pressedButtonDayIndex] = true;

      _daysResponse[_pressedButtonDayIndex] = response;

    }

    dom.Document document = parser.parse(response.body);

    final e1 = document.querySelectorAll('.img_list .thumb');

    final e2 = document.querySelectorAll('.img_list .desc');

    final e3 = document.querySelectorAll('.img_list .rating_type');



    List<List<String>> infoCollection = List<List<String>>();

    List<String> info = List<String>();



    for(int i=0; i<e1.length; i++){

      info.add(e1[i].getElementsByTagName('img')[0].attributes['src']);

      info.add(e1[i].getElementsByTagName('a')[0].attributes['title']);

      info.add(e2[i].getElementsByTagName('a')[0].innerHtml);

      info.add(e3[i].getElementsByTagName('strong')[0].innerHtml);

      infoCollection.add(info);

    }

    _controller.sink.add(infoCollection);

  }

And I'm showing this images, titles, artists and rate by GridView like below

Widget _getWebtoonGridView() {

    return StreamBuilder(

      stream: _controller.stream.asBroadcastStream(),

      builder: (BuildContext context, AsyncSnapshot<List> snapshot){

        if(snapshot.hasError)

          print(snapshot.error);

        else if(snapshot.hasData){

          return GridView.count(

            crossAxisCount: 3,

            childAspectRatio: 0.6,

            children: List.generate(snapshot.data.length, (index){

              return _getWebtoonInfo(index, snapshot.data[index]);

            }),

          );

        }

        else if(snapshot.connectionState != ConnectionState.done)

          return Center(child: CircularProgressIndicator());

      },

    );

  }

But "Stream has already been listened to" error is occurring continuously, what is the problem about my StreamController??

How can I fix it?

StackTrace

I/flutter (21411): ══╡ EXCEPTION CAUGHT BY WIDGETS LIBRARY
╞═══════════════════════════════════════════════════════════ I/flutter
(21411): The following StateError was thrown building Expanded(flex:
1): I/flutter (21411): Bad state: Stream has already been listened to.
I/flutter (21411): I/flutter (21411): When the exception was thrown,
this was the stack: I/flutter (21411): #4

_StreamBuilderBaseState._subscribe (package:flutter/src/widgets/async.dart:135:37) I/flutter (21411): #5
_StreamBuilderBaseState.initState (package:flutter/src/widgets/async.dart:109:5) I/flutter (21411): #6

StatefulElement._firstBuild
(package:flutter/src/widgets/framework.dart:3830:58) I/flutter
(21411): #7 ComponentElement.mount
(package:flutter/src/widgets/framework.dart:3696:5) I/flutter (21411):

8 Element.inflateWidget (package:flutter/src/widgets/framework.dart:2950:14) I/flutter

(21411): #9 Element.updateChild
(package:flutter/src/widgets/framework.dart:2753:12)

StreamController variable

StreamController<List<List<String>>> _controller = StreamController<List<List<String>>>.broadcast();

gridview controller flutter

share|improve this question

edited Jan 1 at 8:18

baeharam

asked Jan 1 at 8:02

baeharambaeharam

498

• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  whats the stacktrace (first few frames)?
  
  – pskink
  Jan 1 at 8:07
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  @pskink I added
  
  – baeharam
  Jan 1 at 8:10
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  how do you your StreamController?
  
  – pskink
  Jan 1 at 8:15
  
  
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  @pskink I added
  
  – baeharam
  Jan 1 at 8:19
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  so why do you need .asBroadcastStream()? remove it, hot restart your app and see what happens
  
  – pskink
  Jan 1 at 8:26
  

  
  
  
  

 | 
show 5 more comments

0

What I'm doing is to fetch cartoon list and show by GridView. Below code is fetching data

Future<void> _getWebtoonData() async {

    var response;

    if(_daysReceivedResponse[_pressedButtonDayIndex]){

      response = _daysResponse[_pressedButtonDayIndex];

    } else {

      response= await http.get('https://comic.naver.com/webtoon/weekdayList.nhn?week='+_currentWebtoonAddress);

      _daysReceivedResponse[_pressedButtonDayIndex] = true;

      _daysResponse[_pressedButtonDayIndex] = response;

    }

    dom.Document document = parser.parse(response.body);

    final e1 = document.querySelectorAll('.img_list .thumb');

    final e2 = document.querySelectorAll('.img_list .desc');

    final e3 = document.querySelectorAll('.img_list .rating_type');



    List<List<String>> infoCollection = List<List<String>>();

    List<String> info = List<String>();



    for(int i=0; i<e1.length; i++){

      info.add(e1[i].getElementsByTagName('img')[0].attributes['src']);

      info.add(e1[i].getElementsByTagName('a')[0].attributes['title']);

      info.add(e2[i].getElementsByTagName('a')[0].innerHtml);

      info.add(e3[i].getElementsByTagName('strong')[0].innerHtml);

      infoCollection.add(info);

    }

    _controller.sink.add(infoCollection);

  }

And I'm showing this images, titles, artists and rate by GridView like below

Widget _getWebtoonGridView() {

    return StreamBuilder(

      stream: _controller.stream.asBroadcastStream(),

      builder: (BuildContext context, AsyncSnapshot<List> snapshot){

        if(snapshot.hasError)

          print(snapshot.error);

        else if(snapshot.hasData){

          return GridView.count(

            crossAxisCount: 3,

            childAspectRatio: 0.6,

            children: List.generate(snapshot.data.length, (index){

              return _getWebtoonInfo(index, snapshot.data[index]);

            }),

          );

        }

        else if(snapshot.connectionState != ConnectionState.done)

          return Center(child: CircularProgressIndicator());

      },

    );

  }

But "Stream has already been listened to" error is occurring continuously, what is the problem about my StreamController??

How can I fix it?

StackTrace

I/flutter (21411): ══╡ EXCEPTION CAUGHT BY WIDGETS LIBRARY
╞═══════════════════════════════════════════════════════════ I/flutter
(21411): The following StateError was thrown building Expanded(flex:
1): I/flutter (21411): Bad state: Stream has already been listened to.
I/flutter (21411): I/flutter (21411): When the exception was thrown,
this was the stack: I/flutter (21411): #4

_StreamBuilderBaseState._subscribe (package:flutter/src/widgets/async.dart:135:37) I/flutter (21411): #5
_StreamBuilderBaseState.initState (package:flutter/src/widgets/async.dart:109:5) I/flutter (21411): #6

StatefulElement._firstBuild
(package:flutter/src/widgets/framework.dart:3830:58) I/flutter
(21411): #7 ComponentElement.mount
(package:flutter/src/widgets/framework.dart:3696:5) I/flutter (21411):

8 Element.inflateWidget (package:flutter/src/widgets/framework.dart:2950:14) I/flutter

(21411): #9 Element.updateChild
(package:flutter/src/widgets/framework.dart:2753:12)

StreamController variable

StreamController<List<List<String>>> _controller = StreamController<List<List<String>>>.broadcast();

gridview controller flutter

share|improve this question

edited Jan 1 at 8:18

baeharam

asked Jan 1 at 8:02

baeharambaeharam

498

• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  whats the stacktrace (first few frames)?
  
  – pskink
  Jan 1 at 8:07
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  @pskink I added
  
  – baeharam
  Jan 1 at 8:10
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  how do you your StreamController?
  
  – pskink
  Jan 1 at 8:15
  
  
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  @pskink I added
  
  – baeharam
  Jan 1 at 8:19
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  so why do you need .asBroadcastStream()? remove it, hot restart your app and see what happens
  
  – pskink
  Jan 1 at 8:26
  

  
  
  
  

 | 
show 5 more comments

0

0

0

What I'm doing is to fetch cartoon list and show by GridView. Below code is fetching data

Future<void> _getWebtoonData() async {

    var response;

    if(_daysReceivedResponse[_pressedButtonDayIndex]){

      response = _daysResponse[_pressedButtonDayIndex];

    } else {

      response= await http.get('https://comic.naver.com/webtoon/weekdayList.nhn?week='+_currentWebtoonAddress);

      _daysReceivedResponse[_pressedButtonDayIndex] = true;

      _daysResponse[_pressedButtonDayIndex] = response;

    }

    dom.Document document = parser.parse(response.body);

    final e1 = document.querySelectorAll('.img_list .thumb');

    final e2 = document.querySelectorAll('.img_list .desc');

    final e3 = document.querySelectorAll('.img_list .rating_type');



    List<List<String>> infoCollection = List<List<String>>();

    List<String> info = List<String>();



    for(int i=0; i<e1.length; i++){

      info.add(e1[i].getElementsByTagName('img')[0].attributes['src']);

      info.add(e1[i].getElementsByTagName('a')[0].attributes['title']);

      info.add(e2[i].getElementsByTagName('a')[0].innerHtml);

      info.add(e3[i].getElementsByTagName('strong')[0].innerHtml);

      infoCollection.add(info);

    }

    _controller.sink.add(infoCollection);

  }

And I'm showing this images, titles, artists and rate by GridView like below

Widget _getWebtoonGridView() {

    return StreamBuilder(

      stream: _controller.stream.asBroadcastStream(),

      builder: (BuildContext context, AsyncSnapshot<List> snapshot){

        if(snapshot.hasError)

          print(snapshot.error);

        else if(snapshot.hasData){

          return GridView.count(

            crossAxisCount: 3,

            childAspectRatio: 0.6,

            children: List.generate(snapshot.data.length, (index){

              return _getWebtoonInfo(index, snapshot.data[index]);

            }),

          );

        }

        else if(snapshot.connectionState != ConnectionState.done)

          return Center(child: CircularProgressIndicator());

      },

    );

  }

But "Stream has already been listened to" error is occurring continuously, what is the problem about my StreamController??

How can I fix it?

StackTrace

I/flutter (21411): ══╡ EXCEPTION CAUGHT BY WIDGETS LIBRARY
╞═══════════════════════════════════════════════════════════ I/flutter
(21411): The following StateError was thrown building Expanded(flex:
1): I/flutter (21411): Bad state: Stream has already been listened to.
I/flutter (21411): I/flutter (21411): When the exception was thrown,
this was the stack: I/flutter (21411): #4

_StreamBuilderBaseState._subscribe (package:flutter/src/widgets/async.dart:135:37) I/flutter (21411): #5
_StreamBuilderBaseState.initState (package:flutter/src/widgets/async.dart:109:5) I/flutter (21411): #6

StatefulElement._firstBuild
(package:flutter/src/widgets/framework.dart:3830:58) I/flutter
(21411): #7 ComponentElement.mount
(package:flutter/src/widgets/framework.dart:3696:5) I/flutter (21411):

8 Element.inflateWidget (package:flutter/src/widgets/framework.dart:2950:14) I/flutter

(21411): #9 Element.updateChild
(package:flutter/src/widgets/framework.dart:2753:12)

StreamController variable

StreamController<List<List<String>>> _controller = StreamController<List<List<String>>>.broadcast();

gridview controller flutter

share|improve this question

edited Jan 1 at 8:18

baeharam

asked Jan 1 at 8:02

baeharambaeharam

498

What I'm doing is to fetch cartoon list and show by GridView. Below code is fetching data

Future<void> _getWebtoonData() async {

    var response;

    if(_daysReceivedResponse[_pressedButtonDayIndex]){

      response = _daysResponse[_pressedButtonDayIndex];

    } else {

      response= await http.get('https://comic.naver.com/webtoon/weekdayList.nhn?week='+_currentWebtoonAddress);

      _daysReceivedResponse[_pressedButtonDayIndex] = true;

      _daysResponse[_pressedButtonDayIndex] = response;

    }

    dom.Document document = parser.parse(response.body);

    final e1 = document.querySelectorAll('.img_list .thumb');

    final e2 = document.querySelectorAll('.img_list .desc');

    final e3 = document.querySelectorAll('.img_list .rating_type');



    List<List<String>> infoCollection = List<List<String>>();

    List<String> info = List<String>();



    for(int i=0; i<e1.length; i++){

      info.add(e1[i].getElementsByTagName('img')[0].attributes['src']);

      info.add(e1[i].getElementsByTagName('a')[0].attributes['title']);

      info.add(e2[i].getElementsByTagName('a')[0].innerHtml);

      info.add(e3[i].getElementsByTagName('strong')[0].innerHtml);

      infoCollection.add(info);

    }

    _controller.sink.add(infoCollection);

  }

And I'm showing this images, titles, artists and rate by GridView like below

Widget _getWebtoonGridView() {

    return StreamBuilder(

      stream: _controller.stream.asBroadcastStream(),

      builder: (BuildContext context, AsyncSnapshot<List> snapshot){

        if(snapshot.hasError)

          print(snapshot.error);

        else if(snapshot.hasData){

          return GridView.count(

            crossAxisCount: 3,

            childAspectRatio: 0.6,

            children: List.generate(snapshot.data.length, (index){

              return _getWebtoonInfo(index, snapshot.data[index]);

            }),

          );

        }

        else if(snapshot.connectionState != ConnectionState.done)

          return Center(child: CircularProgressIndicator());

      },

    );

  }

But "Stream has already been listened to" error is occurring continuously, what is the problem about my StreamController??

How can I fix it?

StackTrace

I/flutter (21411): ══╡ EXCEPTION CAUGHT BY WIDGETS LIBRARY
╞═══════════════════════════════════════════════════════════ I/flutter
(21411): The following StateError was thrown building Expanded(flex:
1): I/flutter (21411): Bad state: Stream has already been listened to.
I/flutter (21411): I/flutter (21411): When the exception was thrown,
this was the stack: I/flutter (21411): #4

_StreamBuilderBaseState._subscribe (package:flutter/src/widgets/async.dart:135:37) I/flutter (21411): #5
_StreamBuilderBaseState.initState (package:flutter/src/widgets/async.dart:109:5) I/flutter (21411): #6

StatefulElement._firstBuild
(package:flutter/src/widgets/framework.dart:3830:58) I/flutter
(21411): #7 ComponentElement.mount
(package:flutter/src/widgets/framework.dart:3696:5) I/flutter (21411):

8 Element.inflateWidget (package:flutter/src/widgets/framework.dart:2950:14) I/flutter

(21411): #9 Element.updateChild
(package:flutter/src/widgets/framework.dart:2753:12)

StreamController variable

StreamController<List<List<String>>> _controller = StreamController<List<List<String>>>.broadcast();

gridview controller flutter

gridview controller flutter

share|improve this question

edited Jan 1 at 8:18

baeharam

asked Jan 1 at 8:02

baeharambaeharam

498

share|improve this question

edited Jan 1 at 8:18

baeharam

asked Jan 1 at 8:02

baeharambaeharam

498

share|improve this question

share|improve this question

edited Jan 1 at 8:18

baeharam

edited Jan 1 at 8:18

baeharam

edited Jan 1 at 8:18

baeharam

asked Jan 1 at 8:02

baeharambaeharam

498

asked Jan 1 at 8:02

baeharambaeharam

498

asked Jan 1 at 8:02

baeharambaeharam

498

498

• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  whats the stacktrace (first few frames)?
  
  – pskink
  Jan 1 at 8:07
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  @pskink I added
  
  – baeharam
  Jan 1 at 8:10
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  how do you your StreamController?
  
  – pskink
  Jan 1 at 8:15
  
  
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  @pskink I added
  
  – baeharam
  Jan 1 at 8:19
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  so why do you need .asBroadcastStream()? remove it, hot restart your app and see what happens
  
  – pskink
  Jan 1 at 8:26
  

  
  
  
  

 | 
show 5 more comments

• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  whats the stacktrace (first few frames)?
  
  – pskink
  Jan 1 at 8:07
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  @pskink I added
  
  – baeharam
  Jan 1 at 8:10
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  how do you your StreamController?
  
  – pskink
  Jan 1 at 8:15
  
  
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  @pskink I added
  
  – baeharam
  Jan 1 at 8:19
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  so why do you need .asBroadcastStream()? remove it, hot restart your app and see what happens
  
  – pskink
  Jan 1 at 8:26
  

  
  
  
  

whats the stacktrace (first few frames)?

– pskink
Jan 1 at 8:07

whats the stacktrace (first few frames)?

– pskink
Jan 1 at 8:07

@pskink I added

– baeharam
Jan 1 at 8:10

@pskink I added

– baeharam
Jan 1 at 8:10

how do you your StreamController?

– pskink
Jan 1 at 8:15

how do you your StreamController?

– pskink
Jan 1 at 8:15

@pskink I added

– baeharam
Jan 1 at 8:19

@pskink I added

– baeharam
Jan 1 at 8:19

so why do you need .asBroadcastStream()? remove it, hot restart your app and see what happens

– pskink
Jan 1 at 8:26

so why do you need .asBroadcastStream()? remove it, hot restart your app and see what happens

– pskink
Jan 1 at 8:26

 | 
show 5 more comments

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