Incorrect use of parent data widget. expanded widgets must be placed inside flex widgets

Question

I am getting the following error:

i.e.., Another exception was thrown: Incorrect use of ParentDataWidget. showing error on the mobile screen.

 @override
  Widget build(BuildContext context) {

    return MaterialApp(
      title: widget.title,
      theme: ThemeData.light().copyWith(
        platform: _platform ?? Theme.of(context).platform,
      ),
      home: DefaultTabController(
        length: categoryNames.length,
        child: Scaffold(
        appBar: AppBar(
          title: Text(widget.title),
                 ),
        body: SafeArea(
            child: Column(
              children: <Widget>[
                Chewie(
                  controller: _chewieController,
                ),
                TabBar(
                  labelColor:Colors.black,
                  tabs: categoryNames,
                ),
                Expanded(
                  child: TabBarView(
                    children: [
                      ImageList()
                    ],
                  ),
                )
                /*TabBarView(
                  children: [
                    Icon(Icons.directions_car),
                    Icon(Icons.directions_transit),
                    Icon(Icons.directions_bike),
                  ],
                )*/
              ],
            )
        ),
      ),
      ),
    );
  }

It's my code, please check and let me know the issue.

I've just run the code you've posted and I'm not getting the same error, would you be able to post the contents of `categoryNames` or the output of `ImageList()`? The issue is most likely an `Expanded` that's not the direct child of a `Column` or a `Row`, but without more info it's a bit hard to say where exactly it's coming from — greyaurora, Feb 27 '19 at 12:33
categorynames is just a list of names and Imagelist is a class, issue is with expanded itself is showing but apart from this any alternate is there to acheive tabbarview with tabs — Mounika, Feb 27 '19 at 12:37

score 454 · Answer 1 · edited Jan 26 '22 at 10:48

454

Expanded cannot be used inside a Stack.

You should use Expanded only within a Column, Row or Flex

edited Jan 26 '22 at 10:48

iDecode

22,623
19
99
186

answered Jun 26 '19 at 06:53

Bilal Awan

4,730
1
8
15

FWIW, I also got this issue when, after converting a `Column` to a `Stack`, I had a `Spacer` widget as one of the children of the `Stack`. I was scouring my code looking for "Expanded", but there was none. So basically, make sure you have neither an `Expanded` nor a `Spacer` as a child of your `Stack`. – David Chopin Aug 02 '23 at 15:51

score 92 · Answer 2 · edited Nov 30 '20 at 05:27

92

First Rule: use Expanded only within a column, row or flex.

Second Rule: Parent column that have expanded child column must be wrapped with expanded as well

edited Nov 30 '20 at 05:27

TuGordoBello

4,350
9
52
78

answered Jul 19 '20 at 16:10

secreal

1,045
7
5

1

On my case, the issue is because the Expanded/Flexible is not a direct child(ren) in Column's children, but rather inside a GestureRecognizer which is the direct child(ren) of the Column. – Chen Li Yong Mar 11 '21 at 17:51
28

haven't heard a bigger nonsense yet. If expanded can only be a descendant of column, row or flexible how do you suggest we should wrap a column within expanded? – Romeo Mihalcea Aug 06 '21 at 14:14

score 66 · Answer 3 · edited May 31 '23 at 15:19

66

there are many things to get this problem.

for example:

Under ListView don't use Spacer Widget
don't use Positioned under Row or Column
Expanded can only use it must be a descendant of Column Row Flex

edited May 31 '23 at 15:19

Mohammad Rabiee Nasri

1,309
2
7
26

answered Jul 22 '21 at 01:52

Akbar Masterpadi

976
8
15

1

BINGOuuu! Specifically I had a `Spacer()` assigned to the `trailing` of a `ListTile` which is inside a `ListView`. It rendered OK but the error was logged and cause for concern. The big problem here was that the stacktrace does not mention my code at all, so it was difficult to track manually, looking at all the `Expanded()` instances. Example: `ListView( ListTile ( triling: Spacer() ) )` <- This is bad – eriel marimon Jun 02 '22 at 18:34
Thanks. Spacer() is the problems for me – Nas Shihab Aug 12 '23 at 07:42

score 9 · Answer 4 · answered Aug 26 '22 at 14:21

9

My issue is because of Expand

          child: Expanded(
            child: SingleChildScrollView(
              scrollDirection: Axis.vertical,
              child: Column(
                children: getChildren(cubit.listPerformer, state),
              ),

After delete Expand, it works fine.

answered Aug 26 '22 at 14:21

Samet ÖZTOPRAK

3,112
3
32
33

this error goes away but `SingleChildScrollView` still doesnt work. – eqrakhattak Jul 13 '23 at 16:24
It needs to look at your code – Samet ÖZTOPRAK Jul 27 '23 at 20:15

score 6 · Answer 5 · answered Jun 15 '21 at 11:27

6

there's no expanded in my code so i found that using Spacer() too can cause this error if it's inside a listview

answered Jun 15 '21 at 11:27

oth man

185
4
16

Did you find an alternative to use ```Spacer()``` inside the Scrollable item? I want to keep maximum space before the last column child and I want to eliminate Overflow on the Keyboard popup. – Hardik Aug 25 '21 at 10:27

score 5 · Answer 6 · answered Jun 29 '21 at 11:03

5

In my case, I was using Positioned inside a column. Removing it solved the problem!

answered Jun 29 '21 at 11:03

M.AQIB

359
5
11

score 5 · Answer 7 · answered Oct 05 '21 at 11:37

5

I removed a Positioned widget that was inside a Container inside a Stack and the problem "Incorrect use of ParentDataWidget" went away.

answered Oct 05 '21 at 11:37

mjukka

61
1
2

2

It's good to try and help, but in this case there are already a lot of very detailed answers to this question and yours doesn't actually add anything. Before answering have a look at what other people have said, and think about whether you're adding anything new that's clearly relevant to the question. – Craig Graham Oct 06 '21 at 12:31

Thaw Thu Han · Answer 8 · 2021-05-31T18:45:49.110

when I skip the video, the chewie controller shows these errors when I fix in chewie package error gone.

please fix in material_controls.dart here

[remove expanded widget in Stack widget]

return MouseRegion(
  onHover: (_) {
    _cancelAndRestartTimer();
  },
  child: GestureDetector(
    onTap: () => _cancelAndRestartTimer(),
    child: AbsorbPointer(
      absorbing: notifier.hideStuff,
      child: Stack(
        children: [
          if (_latestValue.isBuffering)
            const Expanded(
              child: Center(
                child: CircularProgressIndicator(),
              )
            )
          else
            _buildHitArea(),
          _buildActionBar(),
          Column(
            mainAxisAlignment: MainAxisAlignment.end,
            children: <Widget>[
              if (_subtitleOn)
                Transform.translate(
                  offset: Offset(
                      0.0, notifier.hideStuff ? barHeight * 0.8 : 0.0),
                  child:
                      _buildSubtitles(context, chewieController.subtitle!),
                ),
              _buildBottomBar(context),
            ],
          ),
        ],
      ),
    ),
  ),
);

}

score 1 · Answer 9 · answered Oct 08 '21 at 05:58

1

This Solution works only if you are using Position as a parent of row or column

In my case, I was using Positioned inside a column. Removing it solved the problem!

Else

Always remember to use Expanded in Row, Column or Flex

answered Oct 08 '21 at 05:58

Srikanth

11
5

score 1 · Answer 10 · answered May 15 '23 at 09:03

1

Just remove the Expanded.

You should have to use Expanded whenever needed.

Check the below image for reference.

answered May 15 '23 at 09:03

Sanket Vanani

244
3
7

score 1 · Answer 11 · answered Jul 12 '23 at 17:22

 Padding(
                      padding: const EdgeInsets.symmetric(
                          horizontal: 25, vertical: 20),
                      child: Card(
                        child: SingleChildScrollView(
                          scrollDirection: Axis.horizontal,
                          child: Expanded(child: _buildDataTable(data, fields)),
                        ),
                      ),
                    )

give real life to my device emulator and during other emulator devices working fine

but this is not working on a real device like an Android phone, then follow the rule of

First Rule: Use Expanded only within a column, row, or flex.

Second Rule: Parent columns that have expanded child columns must be wrapped with expanded columns as well.

remove Expanded

Padding(
                      padding: const EdgeInsets.symmetric(
                          horizontal: 25, vertical: 20),
                      child: Card(
                        child: SingleChildScrollView(
                          scrollDirection: Axis.horizontal,
                          child: _buildDataTable(data, fields),
                        ),
                      ),
                    ),

score 0 · Answer 12 · answered Jan 26 '22 at 17:35

0

In my case, I was using Expanded inside a Padding widget. Padding was inside a column but since Expanded was wrapped by a Padding it gave me the error. Simply removing Expanded solved my issue.

answered Jan 26 '22 at 17:35

sithum dilanga

427
7
14

score 0 · Answer 13 · answered Feb 03 '22 at 03:14

0

In my case it was because I was enclosing an Expanded inside a SizedBox, I just enclosed the Expanded inside a Row and that's it.

answered Feb 03 '22 at 03:14

edalvb

581
6
7

score -1 · Answer 14 · answered Dec 18 '22 at 18:36

You can use Expanded as child of scrolling parent like this:

Scaffold(
  body: CustomScrollView(
    physics: const AlwaysScrollableScrollPhysics(),
    slivers: [
      SliverFillRemaining(
        fillOverscroll: true,
        child: Column(
          children: <Widget>[
            Container(color: Colors.red,height: 100),
            Expanded(
              child: Container(color: Colors.purple,),
            ),
          ],
        ),
      )
    ],
  ),
)

Incorrect use of parent data widget. expanded widgets must be placed inside flex widgets

14 Answers14

Linked