How to use Expanded in SingleChildScrollView

0 votes

How to use Expanded in SingleChildScrollView? I have a screen with Image.network, ListView.builder and Row (TextFormField and IconButton). I wrapped ListView with Expanded. How to wrap this column with SingleChildScrollView? I need to move screen when the keyboard is open to see what I am writing. When I wrap my column I have this error.

      body: SingleChildScrollView(
        child: Column(
          children: <Widget>[
            Container(
              child: GestureDetector(
                child:
                Image.network(
                  postOne.imageUrl,
                  fit: BoxFit.fitWidth,
                  height: MediaQuery
                      .of(context)
                      .size
                      .width,
                  width: MediaQuery
                      .of(context)
                      .size
                      .width,
                ),
                onLongPress: () {},
                onDoubleTap: () {},
              ),
            ),
            Expanded(
              //height: MediaQuery.of(context).size.width*0.33,
              child: ListView.builder(
                  itemCount: commentList.length,
                  itemBuilder: (context, position) {
                    return GestureDetector(
                        onLongPress: () {},
                        child: Card(
                          child: Padding(
                            padding: EdgeInsets.all(5.0),
                            child: new CheckboxListTile(
                                title: new Text(commentList
                                    .elementAt(position)
                                    .coment,
                                  style: TextStyle(fontSize: 18.0),),
                                value: values[commentList
                                    .elementAt(position)
                                    .coment],
                                onChanged: (bool value) {}),
                          ),
                        )
                    );
                  }
              ),
            ),
            Container(
              child: Row(
                  crossAxisAlignment: CrossAxisAlignment.start,
                  children: [
                    new Flexible(
                      child: Theme(
                        data: new ThemeData(
                            brightness: Brightness.light,
                            primarySwatch: Colors.grey,
                            inputDecorationTheme: new InputDecorationTheme(
                              labelStyle: new TextStyle(
                                  color: Colors.black45, fontSize: 18.0
                              ),
                            )
                        ),
                        child: new Form(
                          key: _formKey,
                          child: new TextFormField(
                            validator: (value) {
                              if (value.isEmpty) {
                                return 'Please enter the comment';
                              }
                            },
                            controller: commentController,
                            decoration: new InputDecoration(
                              labelText: "Add comment",
                              //hintText: 'Add comment'
                            ),
                            keyboardType: TextInputType.text,
                          ),
                        ),
                      ),
                    ),
                    new Container(
                        margin: EdgeInsets.only(left: 10.0, top: 12.0),
                        child: new IconButton(
                            icon: new Icon(Icons.send, color: Colors.black,),
                            onPressed: () {}
                        )
                    ),
                  ]),
            ),
          ],
        ),
      ),
I/flutter ( 6816): ══╡ EXCEPTION CAUGHT BY RENDERING LIBRARY ╞═════════════════════════════════════════════════════════
I/flutter ( 6816): The following assertion was thrown during performLayout():
I/flutter ( 6816): RenderFlex children have non-zero flex but incoming height constraints are unbounded.
I/flutter ( 6816): When a column is in a parent that does not provide a finite height constraint, for example if it is
I/flutter ( 6816): in a vertical scrollable, it will try to shrink-wrap its children along the vertical axis. Setting a
I/flutter ( 6816): flex on a child (e.g. using Expanded) indicates that the child is to expand to fill the remaining
I/flutter ( 6816): space in the vertical direction.
I/flutter ( 6816): These two directives are mutually exclusive. If a parent is to shrink-wrap its child, the child
I/flutter ( 6816): cannot simultaneously expand to fit its parent.
I/flutter ( 6816): Consider setting mainAxisSize to MainAxisSize.min and using FlexFit.loose fits for the flexible
I/flutter ( 6816): children (using Flexible rather than Expanded). This will allow the flexible children to size
I/flutter ( 6816): themselves to less than the infinite remaining space they would otherwise be forced to take, and
I/flutter ( 6816): then will cause the RenderFlex to shrink-wrap the children rather than expanding to fit the maximum
I/flutter ( 6816): constraints provided by the parent.
I/flutter ( 6816): The affected RenderFlex is:
I/flutter ( 6816):   RenderFlex#9f534 relayoutBoundary=up11 NEEDS-LAYOUT NEEDS-PAINT
I/flutter ( 6816): The creator information is set to:
I/flutter ( 6816):   Column ← _SingleChildViewport ← IgnorePointer-[GlobalKey#3670d] ← Semantics ← Listener ←
I/flutter ( 6816):   _GestureSemantics ← RawGestureDetector-[LabeledGlobalKey<RawGestureDetectorState>#4878e] ←
I/flutter ( 6816):   Listener ← _ScrollableScope ← _ScrollSemantics-[GlobalKey#c5885] ← RepaintBoundary ← CustomPaint ←
I/flutter ( 6816):   ⋯
I/flutter ( 6816): The nearest ancestor providing an unbounded width constraint is:
I/flutter ( 6816):   _RenderSingleChildViewport#155d8 relayoutBoundary=up10 NEEDS-LAYOUT NEEDS-PAINT
I/flutter ( 6816):   creator: _SingleChildViewport ← IgnorePointer-[GlobalKey#3670d] ← Semantics ← Listener ←
I/flutter ( 6816):   _GestureSemantics ← RawGestureDetector-[LabeledGlobalKey<RawGestureDetectorState>#4878e] ←
I/flutter ( 6816):   Listener ← _ScrollableScope ← _ScrollSemantics-[GlobalKey#c5885] ← RepaintBoundary ← CustomPaint ←
I/flutter ( 6816):   RepaintBoundary ← ⋯
I/flutter ( 6816):   parentData: <none> (can use size)
I/flutter ( 6816):   constraints: BoxConstraints(0.0<=w<=440.8, 0.0<=h<=649.3)
I/flutter ( 6816):   size: MISSING
I/flutter ( 6816): See also: https://flutter.dev/layout/
I/flutter ( 6816): If this message did not help you determine the problem, consider using debugDumpRenderTree():
I/flutter ( 6816):   https://flutter.dev/debugging/#rendering-layer
I/flutter ( 6816):   http://docs.flutter.io/flutter/rendering/debugDumpRenderTree.html
I/flutter ( 6816): If none of the above helps enough to fix this problem, please don't hesitate to file a bug:
I/flutter ( 6816):   https://github.com/flutter/flutter/issues/new?template=BUG.md
I/flutter ( 6816): 


Mar 27, 2023 in Flutter by Ashwini
• 5,430 points
12,704 views

1 answer to this question.

0 votes

The error message suggests that the Expanded widget cannot be used within SingleChildScrollView because it requires a bounded height constraint, but SingleChildScrollView provides an unbounded height constraint to its child. To resolve this error, you can try the following:

  1. Remove the Expanded widget and replace it with a fixed-height container. For example, you could wrap your ListView.builder widget with a SizedBox widget and specify a height, like this:

    ​SingleChildScrollView(
      child: Column(
        children: [
          ...
          SizedBox(
            height: 300, // Replace with the desired height
            child: ListView.builder(
              itemCount: commentList.length,
              itemBuilder: (context, position) {
                ...
              }
            ),
          ),
          ...
        ],
      ),
    )
     
  2. If you need your ListView.builder widget to take up as much vertical space as possible while still fitting within the constraints provided by the SingleChildScrollView, you can use a LayoutBuilder widget to get the maximum height available to the ListView.builder and then wrap it with an Expanded widget. Here's an example:

    SingleChildScrollView(
      child: Column(
        children: [
          ...
          LayoutBuilder(
            builder: (context, constraints) {
              return Expanded(
                child: SizedBox(
                  height: constraints.maxHeight,
                  child: ListView.builder(
                    itemCount: commentList.length,
                    itemBuilder: (context, position) {
                      ...
                    }
                  ),
                ),
              );
            },
          ),
          ...
        ],
      ),
    )
     

    This approach will allow the ListView.builder to take up as much space as possible within the constraints provided by the SingleChildScrollView, while still allowing the user to scroll if the content exceeds the available space.

answered Mar 27, 2023 by sarit
• 1,830 points

Related Questions In Flutter

0 votes
1 answer

How to change Android minSdkVersion in Flutter Project?

Yes, you can change the minSdkVersion in ...READ MORE

answered Mar 21, 2023 in Flutter by Tej
8,551 views
0 votes
1 answer

How to implement drop down list in flutter?

You're close! The error you're getting is ...READ MORE

answered Mar 26, 2023 in Flutter by vishalini
3,049 views
0 votes
2 answers

How to create a circle icon button in Flutter?

To create something similar to a FloatingActionButton, ...READ MORE

answered Aug 23, 2023 in Flutter by anonymous
• 140 points
11,304 views
0 votes
1 answer

How to dynamically resize text in Flutter?

You can use the FittedBox widget to ...READ MORE

answered Mar 27, 2023 in Flutter by Tej
7,982 views
0 votes
1 answer

How to present an empty view in flutter?

In Flutter, you can present an empty ...READ MORE

answered Mar 27, 2023 in Flutter by anonymous
3,191 views
0 votes
1 answer

How to Deserialize a list of objects from json in flutter Ask Question?

To deserialize a list of objects from ...READ MORE

answered Mar 28, 2023 in Flutter by vishalini
1,770 views
0 votes
1 answer

What is the future of flutter?

Hi@MD, Flutter is a rather new cross-platform framework ...READ MORE

answered Jul 17, 2020 in Others by akhtar
• 38,230 points
961 views
0 votes
1 answer

What is Flutter?

Hi@akhtar, Flutter is an app SDK for building ...READ MORE

answered Jul 17, 2020 in Others by MD
• 95,440 points
1,121 views
0 votes
1 answer

How to install Flutter in Windows system?

Hi@akhtar, You can follow the below-given steps to ...READ MORE

answered Jul 17, 2020 in Others by MD
• 95,440 points
1,570 views
webinar REGISTER FOR FREE WEBINAR X
REGISTER NOW
webinar_success Thank you for registering Join Edureka Meetup community for 100+ Free Webinars each month JOIN MEETUP GROUP