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[web] SelectionArea in MaterialApp.builder throws "RenderBox was not laid out" on startup (refile of #191508) #193287
Description
Steps to reproduce
flutter create --platforms=web bug- Replace
lib/main.dartwith the code sample below. flutter run -d chrome
This is a refile of #191508, which was closed automatically while it was labelled "waiting for response", although a minimal repro had been posted there (the code sample below is that repro). It still reproduces on stable 3.47.5 (Chrome 154) and on master at 434cd53 (2026-09-24).
Expected results
No exception on startup.
Actual results
On every load, an assertion is thrown while dispatching WidgetsBindingObserver.didChangeViewFocus:
RenderBox was not laid out: RenderStack#1d01a NEEDS-LAYOUT NEEDS-PAINT NEEDS-COMPOSITING-BITS-UPDATE
It comes from _ViewState.didChangeViewFocus → findFirstFocus → FocusNode.rect → RenderBox.size, before the first frame has been laid out (full stack in the logs below). In a release --wasm build the same error is logged as Bad state: RenderBox was not laid out: minified:Class…. The app works normally afterwards.
Workaround: wrapping the route instead (home: SelectionArea(child: ...), with no Overlay in builder) does not throw. The Overlay in builder without the SelectionArea does not throw either.
Code sample
Code sample
import 'package:flutter/material.dart';
void main() => runApp(const MyApp());
class MyApp extends StatelessWidget {
const MyApp({super.key});
@override
Widget build(BuildContext context) {
return MaterialApp(
home: const Scaffold(body: Center(child: Text('hello'))),
builder: (context, child) => Overlay(
initialEntries: [
OverlayEntry(builder: (context) => SelectionArea(child: child ?? const SizedBox.shrink())),
],
),
);
}
}Screenshots or Video
No response
Logs
Logs
flutter run -d chrome (debug, DDC), Flutter 3.47.5, Chrome 154:
══╡ EXCEPTION CAUGHT BY WIDGETS LIBRARY ╞═══════════════════════════════════════════════════════════
The following assertion was thrown while dispatching notifications for
WidgetsBindingObserver.didChangeViewFocus:
Assertion failed:
file://<flutter>/packages/flutter/lib/src/rendering/box.dart:2251:12
hasSize
"RenderBox was not laid out: RenderStack#1d01a NEEDS-LAYOUT NEEDS-PAINT
NEEDS-COMPOSITING-BITS-UPDATE"
When the exception was thrown, this was the stack:
dart-sdk/lib/_internal/js_dev_runtime/private/ddc_runtime/errors.dart 274:3 throw_
dart-sdk/lib/_internal/js_dev_runtime/private/ddc_runtime/errors.dart 44:3 assertFailed
package:flutter/src/rendering/box.dart 2251:12 get size
package:flutter/src/rendering/box.dart 2437:44 get semanticBounds
package:flutter/src/widgets/focus_manager.dart 871:13 get rect
package:flutter/src/widgets/focus_traversal.dart 1399:18 new
package:flutter/src/widgets/focus_traversal.dart 1580:43 <fn>
package:flutter/src/widgets/focus_traversal.dart 1579:41 sort
package:flutter/src/widgets/focus_traversal.dart 1709:7 sortDescendants
package:flutter/src/widgets/focus_traversal.dart 514:55 _sortAllDescendants
package:flutter/src/widgets/focus_traversal.dart 338:9 [_findInitialFocus]
package:flutter/src/widgets/focus_traversal.dart 299:12 findFirstFocus
package:flutter/src/widgets/view.dart 254:33 didChangeViewFocus
package:flutter/src/widgets/binding.dart 1355:17 handleViewFocusChanged
dart-sdk/lib/_internal/js_dev_runtime/private/ddc_runtime/operations.dart 118:77 tear
lib/_engine/engine/platform_dispatcher.dart 1748:5 invoke1
lib/_engine/engine/platform_dispatcher.dart 206:5 invokeOnViewFocusChange
dart-sdk/lib/_internal/js_dev_runtime/private/ddc_runtime/operations.dart 118:77 tear
lib/_engine/engine/platform_dispatcher/view_focus_binding.dart 109:23 [_handleFocusChange]
lib/_engine/engine/platform_dispatcher/view_focus_binding.dart 54:5 <fn>
dart-sdk/lib/async/zone.dart 1034:54 runUnary
dart-sdk/lib/async/zone.dart 989:26 <fn>
dart-sdk/lib/_internal/js_dev_runtime/patch/js_allow_interop_patch.dart 218:27 _callDartFunctionFast1
dart-sdk/lib/_internal/js_dev_runtime/patch/js_allow_interop_patch.dart 78:15 ret
lib/_engine/engine/dom.dart 518:8 DomElement.focusWithoutScroll
lib/_engine/engine/platform_dispatcher/view_focus_binding.dart 45:24 changeViewFocus
lib/_engine/engine/platform_dispatcher.dart 215:5 requestViewFocusChange
package:flutter/src/widgets/view.dart 233:29 [_scopeFocusChangeListener]
dart-sdk/lib/_internal/js_dev_runtime/private/ddc_runtime/operations.dart 118:77 tear
package:flutter/src/foundation/change_notifier.dart 435:24 notifyListeners
package:flutter/src/widgets/focus_manager.dart 1139:5 [_notify]
package:flutter/src/widgets/focus_manager.dart 2011:11 applyFocusChangesIfNeeded
dart-sdk/lib/_internal/js_dev_runtime/private/ddc_runtime/operations.dart 118:77 tear
dart-sdk/lib/async/schedule_microtask.dart 40:34 _microtaskLoop
dart-sdk/lib/async/schedule_microtask.dart 49:5 _startMicrotaskLoop
dart-sdk/lib/_internal/js_dev_runtime/private/ddc_runtime/operations.dart 118:77 tear
dart-sdk/lib/_internal/js_dev_runtime/patch/async_patch.dart 183:69 <fn>
════════════════════════════════════════════════════════════════════════════════════════════════════Flutter Doctor output
Doctor output
[✓] Flutter (Channel stable, 3.47.5, on macOS 27.0 26A428 darwin-arm64, locale en-GB) [18.0s]
• Flutter version 3.47.5 on channel stable at ~/.local/share/mise/http-tarballs/853f502e6161aaf03f395ae268c089f77546297338dd033b403474e8af39e7b8_strip_1
• Upstream repository https://github.com/flutter/flutter.git
• Framework revision 6a19cca564 (7 days ago), 2026-09-17 14:13:22 -0400
• Engine revision af7e796e16
• Dart version 3.13.4
• DevTools version 2.60.0
• Feature flags: enable-web, enable-linux-desktop, enable-macos-desktop, enable-windows-desktop, enable-android, enable-ios, cli-animations, enable-native-assets, enable-record-use, enable-swift-package-manager, omit-legacy-version-file, enable-lldb-debugging, enable-uiscene-migration
[✓] Android toolchain - develop for Android devices (Android SDK version 36.1.0) [19.7s]
• Android SDK at ~/Library/Android/sdk
• Emulator version 36.2.11.0 (build_id 14212360) (CL:N/A)
• Platform android-36, build-tools 36.1.0
! Multiple adb binaries found. This can cause conflicts and device detection issues:
- ~/Library/Android/sdk/platform-tools/adb
- /opt/homebrew/Caskroom/android-platform-tools/37.0.1/platform-tools/adb
• Java binary at: /Applications/Android Studio.app/Contents/jbr/Contents/Home/bin/java
This is the JDK bundled with the latest Android Studio installation on this machine.
To manually set the JDK path, use: `flutter config --jdk-dir="path/to/jdk"`.
• Java version OpenJDK Runtime Environment (build 25.0.3+-15898627-b508.16)
• All Android licenses accepted.
[!] Xcode - develop for iOS and macOS (Xcode 27.0) [20.1s]
• Xcode at /Applications/Xcode.app/Contents/Developer
• Build 27A266a
✗ Unable to get list of installed Simulator runtimes.
! CocoaPods not installed.
CocoaPods is a package manager for iOS or macOS platform code.
Without CocoaPods, plugins will not work on iOS or macOS.
For more info, see https://flutter.dev/to/platform-plugins
For installation instructions, see https://guides.cocoapods.org/using/getting-started.html#installation
[✓] Chrome - develop for the web [3ms]
• Chrome at /Applications/Google Chrome.app/Contents/MacOS/Google Chrome
[✓] Connected device (2 available) [12.2s]
• macOS (desktop) • macos • darwin-arm64 • macOS 27.0 26A428 darwin-arm64
• Chrome (web) • chrome • web-javascript • Google Chrome 154.0.8037.58
[✓] Network resources [543ms]
• All expected network resources are available.
! Doctor found issues in 1 category.
Activity
BartSimpson001 commentedon Sep 24, 2026
I’m investigating this issue and tracing the focus and layout lifecycle to identify the root cause. I’ll share my findings once I have more information.
suryaKommana2662 commentedon Sep 25, 2026
@feldgendler Thanks for the report. I was able to reproduce the issue locally on Chrome using the provided reproduction. routing to the
team-text-inputfor further investigation.The application launches successfully, but the following assertion is thrown during WidgetsBindingObserver.didChangeViewFocus:
The stack trace includes:
Flutter Doctor Output
mdebbar commentedon Sep 30, 2026
Are you seeing this issue on other platforms too? This seems like a framework issue, not a web one.
feldgendler commentedon Sep 30, 2026
Tested on macOS desktop and Android (3.47.5): the repro doesn't throw there. But it's not web-specific code. It reproduces on the Dart VM in a plain
flutter testwhen a view-focus event (focused,forward) arrives after build and before the first layout:This throws the same
RenderBox was not laid outfrom_ViewState.didChangeViewFocus→findFirstFocus→ReadingOrderTraversalPolicy.sort. The two variants from the issue (noSelectionArea, orSelectionAreaaroundhome) pass. The web is where it shows because the web engine runs the warm-up frame'sbeginFrameanddrawFramein separate timers, so the view-focus event from the startup focus change lands before layout. macOS sends directionundefined, which skipsfindFirstFocus, and Android/iOS don't send view-focus events. So this looks like a framework issue indidChangeViewFocus/ the traversal policy reading rects of nodes that aren't laid out yet.1 remaining item
dorklein commentedon Nov 13, 2026
Note
🤖 Claude Opus 5.5 responding on behalf of Dor Klein
Still reproduces on stable 3.50.0, and it isn't specific to
SelectionAreaorOverlay: a plainFocusinMaterialApp.builderis enough. The node that isn't laid out is thenRenderSemanticsAnnotations.With the VM test from the comment above (same results on 3.50.0 and 3.47.8):
MaterialApp.builderOverlay+SelectionArea)RenderBox was not laid out: RenderSemanticsAnnotations(context, child) => Focus(child: Stack(children: [child!]))Focus(autofocus: true, ...)MaterialApp.router, no builderIn a real web app (3.50.0, debug), the trace also shows where the early view-focus event comes from: the framework's own first focus change, which the web engine sends back synchronously.
My reading: any app with a focus node above the navigator in
builderlikely hits this on every web load.