SingleChildScrollView with child Center throws unhelpful error

[Lasslos]

I had an error today whose cause I don't totally understand, and the error message was unhelpful and told me to file an issue here

Steps to Reproduce

1. Execute flutter run on the code sample

Expected results:
Working UI with pageView

Actual results:

Unhelpful Error Message

======== Exception caught by rendering library =====================================================
The following assertion was thrown during paint():
'package:flutter/src/rendering/sliver_multi_box_adaptor.dart': Failed assertion: line 550 pos 12: 'child.hasSize': is not true.


Either the assertion indicates an error in the framework itself, or we should provide substantially more information in this error message to help you determine and fix the underlying cause.
In either case, please report this assertion by filing a bug on GitHub:
  https://github.com/flutter/flutter/issues/new?template=2_bug.md

The relevant error-causing widget was: 
  PageView PageView:file:///C:/Users/Laslo/Development/test_project/lib/main.dart:22:22
When the exception was thrown, this was the stack: 
#2      RenderSliverMultiBoxAdaptor.paintExtentOf (package:flutter/src/rendering/sliver_multi_box_adaptor.dart:550:12)
#3      RenderSliverMultiBoxAdaptor.paint (package:flutter/src/rendering/sliver_multi_box_adaptor.dart:659:79)
#4      RenderObject._paintWithContext (package:flutter/src/rendering/object.dart:2796:7)
#5      PaintingContext.paintChild (package:flutter/src/rendering/object.dart:239:13)
#6      RenderSliverEdgeInsetsPadding.paint (package:flutter/src/rendering/sliver_padding.dart:286:15)
#7      RenderObject._paintWithContext (package:flutter/src/rendering/object.dart:2796:7)
#8      PaintingContext.paintChild (package:flutter/src/rendering/object.dart:239:13)
#9      RenderViewportBase._paintContents (package:flutter/src/rendering/viewport.dart:677:17)
#10     PaintingContext.pushLayer (package:flutter/src/rendering/object.dart:460:12)
#11     PaintingContext.pushClipRect (package:flutter/src/rendering/object.dart:520:7)
#12     RenderViewportBase.paint (package:flutter/src/rendering/viewport.dart:652:38)
#13     RenderObject._paintWithContext (package:flutter/src/rendering/object.dart:2796:7)
#14     PaintingContext._repaintCompositedChild (package:flutter/src/rendering/object.dart:155:11)
#15     PaintingContext.repaintCompositedChild (package:flutter/src/rendering/object.dart:98:5)
#16     PipelineOwner.flushPaint (package:flutter/src/rendering/object.dart:1116:31)
#17     RendererBinding.drawFrame (package:flutter/src/rendering/binding.dart:515:19)
#18     WidgetsBinding.drawFrame (package:flutter/src/widgets/binding.dart:884:13)
#19     RendererBinding._handlePersistentFrameCallback (package:flutter/src/rendering/binding.dart:378:5)
#20     SchedulerBinding._invokeFrameCallback (package:flutter/src/scheduler/binding.dart:1175:15)
#21     SchedulerBinding.handleDrawFrame (package:flutter/src/scheduler/binding.dart:1104:9)
#22     SchedulerBinding.scheduleWarmUpFrame.<anonymous closure> (package:flutter/src/scheduler/binding.dart:881:7)
(elided 6 frames from class _AssertionError, class _RawReceivePortImpl, class _Timer, and dart:async-patch)
The following RenderObject was being processed when the exception was fired: RenderSliverFillViewport#d1392 relayoutBoundary=up2
...  needs compositing
...  parentData: paintOffset=Offset(0.0, 0.0) (can use size)
...  constraints: SliverConstraints(AxisDirection.right, GrowthDirection.forward, ScrollDirection.idle, scrollOffset: 0.0, remainingPaintExtent: 411.4, crossAxisExtent: 867.4, crossAxisDirection: AxisDirection.down, viewportMainAxisExtent: 411.4, remainingCacheExtent: 411.4, cacheOrigin: 0.0)
...  geometry: SliverGeometry(scrollExtent: Infinity, paintExtent: 411.4, maxPaintExtent: Infinity, hasVisualOverflow: true, cacheExtent: 411.4)
...    scrollExtent: Infinity
...    paintExtent: 411.4
...    maxPaintExtent: Infinity
...    hasVisualOverflow: true
...    cacheExtent: 411.4
...  currently live children: 0 to 0
RenderObject: RenderSliverFillViewport#d1392 relayoutBoundary=up2
  needs compositing
  parentData: paintOffset=Offset(0.0, 0.0) (can use size)
  constraints: SliverConstraints(AxisDirection.right, GrowthDirection.forward, ScrollDirection.idle, scrollOffset: 0.0, remainingPaintExtent: 411.4, crossAxisExtent: 867.4, crossAxisDirection: AxisDirection.down, viewportMainAxisExtent: 411.4, remainingCacheExtent: 411.4, cacheOrigin: 0.0)
  geometry: SliverGeometry(scrollExtent: Infinity, paintExtent: 411.4, maxPaintExtent: Infinity, hasVisualOverflow: true, cacheExtent: 411.4)
    scrollExtent: Infinity
    paintExtent: 411.4
    maxPaintExtent: Infinity
    hasVisualOverflow: true
    cacheExtent: 411.4
  currently live children: 0 to 0
...  child with index 0: RenderIndexedSemantics#d3b9d NEEDS-PAINT
...    needs compositing
...    parentData: index=0; layoutOffset=0.0
...    constraints: BoxConstraints(w=411.4, h=867.4)
...    size: MISSING
...    index: 0
...    child: RenderRepaintBoundary#56928 NEEDS-PAINT
...      needs compositing
...      parentData: <none> (can use size)
...      constraints: BoxConstraints(w=411.4, h=867.4)
...      size: MISSING
...      usefulness ratio: no metrics collected yet (never painted)
...      child: RenderFlex#b805c NEEDS-PAINT
...        needs compositing
...        parentData: <none> (can use size)
...        constraints: BoxConstraints(w=411.4, h=867.4)
...        size: MISSING
...        direction: horizontal
...        mainAxisAlignment: start
...        mainAxisSize: max
...        crossAxisAlignment: center
...        textDirection: ltr
...        verticalDirection: down
...        child 1: RenderRepaintBoundary#31f83 relayoutBoundary=up1 NEEDS-PAINT
...          needs compositing
...          parentData: offset=Offset(0.0, 0.0); flex=null; fit=null (can use size)
...          constraints: BoxConstraints(0.0<=w<=Infinity, 0.0<=h<=867.4)
...          size: MISSING
...          usefulness ratio: no metrics collected yet (never painted)
...        child 2: RenderRepaintBoundary#3a7da NEEDS-LAYOUT NEEDS-PAINT
...          needs compositing
...          parentData: offset=Offset(0.0, 0.0); flex=null; fit=null
...          constraints: MISSING
...          size: MISSING
...          usefulness ratio: no metrics collected yet (never painted)
====================================================================================================

Code sample

import 'package:flutter/material.dart';

void main() {
  runApp(const MyApp());
}

class MyApp extends StatelessWidget {
  const MyApp({Key? key}) : super(key: key);

  @override
  Widget build(BuildContext context) => const MaterialApp(
    home: Home(),
  );
}

class Home extends StatelessWidget {
  const Home({Key? key}) : super(key: key);

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      body: PageView.builder(
        itemBuilder: (context, index) {
          return Row(
            children: [
              ListView(
                children: List.generate(50, (index) => Text("Index $index")),
              ),
              ListView(
                children: List.generate(50, (index) => Text("Index $index")),
              ),
            ],
          );
        },
      ),
    );
  }
}

Logs

C:\Users\Laslo>cd Development\test_project
C:\Users\Laslo\Development\test_project>flutter analyze                                                                 Analyzing test_project...
No issues found! (ran in 3.8s) 
C:\Users\Laslo\Development\test_project>

C:\Users\Laslo\Development\test_project>flutter doctor -v                                                               
[√] Flutter (Channel stable, 3.3.3, on Microsoft Windows [Version 10.0.19043.2075], locale de-DE)                           
• Flutter version 3.3.3 on channel stable at C:\Users\Laslo\flutter                                                     
• Upstream repository https://github.com/flutter/flutter.git                                                            
• Framework revision 18a827f393 (7 days ago), 2022-09-28 10:03:14 -0700                                                 
• Engine revision 5c984c26eb                                                                                            
• Dart version 2.18.2                                                                                                   
• DevTools version 2.15.0                                                                                                                                                                                                                   
[!] Android toolchain - develop for Android devices (Android SDK version 33.0.0)                                            
• Android SDK at C:\Users\Laslo\AppData\Local\Android\sdk                                                               
X cmdline-tools component is missing                                                                                      
Run `path/to/sdkmanager --install "cmdline-tools;latest"`                                                               
See https://developer.android.com/studio/command-line for more details.                                               
X Android license status unknown.                                                                                         
Run `flutter doctor --android-licenses` to accept the SDK licenses.                                                     
See https://flutter.dev/docs/get-started/install/windows#android-setup for more details.                                                                                                                                                  [√] Chrome - develop for the web                                                                                            
• Chrome at C:\Program Files\Google\Chrome\Application\chrome.exe                                                                                                                                                                           [X] Visual Studio - develop for Windows                                                                                     
X Visual Studio not installed; this is necessary for Windows development.                                                 
Download at https://visualstudio.microsoft.com/downloads/.                                                              
Please install the "Desktop development with C++" workload, including all of its default components                                                                                                                                       [√] Android Studio (version 2021.3)                                                                                         
• Android Studio at C:\Users\Laslo\AppData\Local\JetBrains\Toolbox\apps\AndroidStudio\ch-0\213.7172.25.2113.9014738     • Flutter plugin version 70.2.3                                                                                         
• Dart plugin version 213.7433                                                                                          
• Java version OpenJDK Runtime Environment (build 11.0.13+0-b1751.21-8125866)                                                                                                                                                               
[√] IntelliJ IDEA Ultimate Edition (version 2022.2)                                                                         
• IntelliJ at C:\Users\Laslo\AppData\Local\JetBrains\Toolbox\apps\IDEA-U\ch-0\222.4167.29                               
• Flutter plugin version 70.2.5                                                                                         
• Dart plugin version 222.4167.21                                                                                                                                                                                                           
[√] Connected device (4 available)                                                                                          
• sdk gphone64 x86 64 (mobile) • emulator-5554 • android-x64    • Android 13 (API 33) (emulator)                        
• Windows (desktop)            
• windows       
• windows-x64    
• Microsoft Windows [Version 10.0.19043.2075]           
• Chrome (web)                 
• chrome       
 • web-javascript 
• Google Chrome 105.0.5195.127                          
• Edge (web)                  
• edge          
• web-javascript 
• Microsoft Edge 105.0.1343.53                                                                                                                                              [√] 
HTTP Host Availability                                                                                                  
• All required HTTP hosts are available                                                                                                                                                                                                     
! Doctor found issues in 2 categories.                                                                                                                                                                                                          
C:\Users\Laslo\Development\test_project>  

[exaby73]

Hello @Lasslos . Thank you for filing this issue. Can you please provide the following information?

• A complete and minimal, reproducible example.

Please provide the information in the form of text. See how to make collapsible sections with Markdown here.

[Lasslos]

I have updated the original post. I hope this is minimal enough

[exaby73]

Hello @Lasslos. From the error logs, this looks like it's expected. The error logs clearly mention the error widget being PageView. That's because the PageViews children is making it stretch to an infinite height which is also mentioned. I do not think it's possible for Flutter to figure out exactly which widget is causing this since it will paint the PageView and it's the PageView that is reporting an infinite height and not it's children. Also the assertion on the first line indicates to the developer that the assertion is false for hasSize. That along side the stack trace is enough information to determine what the issue is.

Due to above reasons, I am closing this issue. Id you disagree, please comment and I can reopen it. Thank you.

[github-actions]

This thread has been automatically locked since there has not been any recent activity after it was closed. If you are still experiencing a similar issue, please open a new bug, including the output of flutter doctor -v and a minimal reproduction of the issue.