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[Widget Preview] Isolate PageStorage scope in widget preview group expansion tile - #191378
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…pansion tile When a preview group is collapsed and re-expanded, descendant scrollables (which search ancestor elements for a PageStorageKey when restoring scroll offset) inherit the PageStorageKey from the ExpansionTile and attempt to read the ExpansionTile's boolean expansion state as a double, throwing a TypeError. This wraps the ExpansionTile children in a PageStorage widget with a new PageStorageBucket, preventing descendant scrollable widgets from inheriting the ExpansionTile's PageStorageKey. Fixes flutter#191242
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This pull request wraps the preview layout builders in a PageStorage widget to prevent descendant scrollables from inheriting the PageStorageKey of the parent ExpansionTile. However, instantiating PageStorageBucket directly inside the build method of the StatelessWidget WidgetPreviewGroupWidget will cause a new bucket to be created on every rebuild, losing any stored state. It is recommended to convert WidgetPreviewGroupWidget to a StatefulWidget and persist the PageStorageBucket in its state.
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| PageStorage( | ||
| bucket: PageStorageBucket(), |
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Instantiating PageStorageBucket directly inside the build method of a StatelessWidget causes a new bucket to be created on every rebuild. This defeats the purpose of PageStorage because any state stored in the bucket (such as scroll offsets of descendant scrollables) will be lost whenever WidgetPreviewGroupWidget rebuilds. To fix this, WidgetPreviewGroupWidget should be converted to a StatefulWidget, and the PageStorageBucket should be instantiated and stored in the State class so that it persists across rebuilds.
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Addressed: Converted WidgetPreviewGroupWidget to a StatefulWidget and moved PageStorageBucket instantiation to the State class so it persists across rebuilds.
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| PageStorage( | ||
| bucket: PageStorageBucket(), |
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Instantiating PageStorageBucket directly inside the build method of a StatelessWidget causes a new bucket to be created on every rebuild. This defeats the purpose of PageStorage because any state stored in the bucket (such as scroll offsets of descendant scrollables) will be lost whenever WidgetPreviewGroupWidget rebuilds. To fix this, WidgetPreviewGroupWidget should be converted to a StatefulWidget, and the PageStorageBucket should be instantiated and stored in the State class so that it persists across rebuilds.
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Addressed: Converted WidgetPreviewGroupWidget to a StatefulWidget and moved PageStorageBucket instantiation to the State class so it persists across rebuilds.
…o persist PageStorageBucket
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Roll Flutter from c2437523d308 to 65c9a8dc60bc (195 revisions) flutter/flutter@c243752...65c9a8d 2026-08-22 [email protected] Roll ICU from d578f2e8b7bd to 8cc91d9b6ab9 (1 revision) (flutter/flutter#191542) 2026-08-22 [email protected] Roll Skia from 666a9b3d5cf0 to ad2106c0bb64 (3 revisions) (flutter/flutter#191527) 2026-08-22 [email protected] Roll Fuchsia Test Scripts from KaOq3EE4qJ9fnaaaK... to 0iCv10IlKfiilEBOU... (flutter/flutter#191524) 2026-08-22 [email protected] [flutter_tools] Add tests for negative lookahead regex in test runner and batch entrypoints (flutter/flutter#191438) 2026-08-22 [email protected] Roll Skia from 0c37868737fa to 666a9b3d5cf0 (2 revisions) (flutter/flutter#191518) 2026-08-21 [email protected] Revert "[input] Migrate fuchsia.ui.pointerinjector to TouchSource (#190855) (flutter/flutter#191509) 2026-08-21 [email protected] Fixes windows gallery benchmarks by forcing mobile layout (flutter/flutter#191507) 2026-08-21 [email protected] [flutter_tools] Restrict WebAssetServer source resolution to source map extensions (flutter/flutter#191501) 2026-08-21 [email protected] Roll Skia from f6900c5b8439 to 0c37868737fa (2 revisions) (flutter/flutter#191504) 2026-08-21 [email protected] Refactor `FlutterDevice.connect` and VM service discovery (flutter/flutter#191221) 2026-08-21 [email protected] [flutter_tools] Fix crash when migrating flow-style exclude lists in analysis_options.yaml (flutter/flutter#191269) 2026-08-21 [email protected] [rules] Add packages/flutter_tools/gradle/AGENTS.md rules (flutter/flutter#191486) 2026-08-21 [email protected] [flutter_tools] refactor CLI argument architecture with typed option descriptors and bundles (PoC) (flutter/flutter#191018) 2026-08-21 [email protected] tools: Extract Dart SDK to temp directory before moving to final location (flutter/flutter#191263) 2026-08-21 [email protected] [web] Move CanvasKit fragment shader classes to canvaskit/fragment_shader.dart (flutter/flutter#191451) 2026-08-21 [email protected] Roll Fuchsia Linux SDK from GCQlmt6h-esJsNubS... to ic6GjOSn-KN508XyK... (flutter/flutter#191485) 2026-08-21 [email protected] [Widget Preview] Isolate PageStorage scope in widget preview group expansion tile (flutter/flutter#191378) 2026-08-21 [email protected] [flutter_tools] Deprecate --build and --no-build flags on flutter run (flutter/flutter#191358) 2026-08-21 [email protected] Roll Skia from 70988bed1b3b to f6900c5b8439 (2 revisions) (flutter/flutter#191481) 2026-08-21 [email protected] Roll Packages from 1785501 to 252bb33 (6 revisions) (flutter/flutter#191480) 2026-08-21 [email protected] Roll Fuchsia Linux SDK from 20IJas24bZiNmCZTK... to GCQlmt6h-esJsNubS... (flutter/flutter#191415) 2026-08-21 [email protected] Roll Skia from 2ba6971bd0d1 to 70988bed1b3b (2 revisions) (flutter/flutter#191476) 2026-08-21 [email protected] Roll Skia from 1d5f72537ba6 to 2ba6971bd0d1 (2 revisions) (flutter/flutter#191473) 2026-08-21 [email protected] Roll Skia from 2c25efd2e369 to 1d5f72537ba6 (1 revision) (flutter/flutter#191472) 2026-08-21 [email protected] Roll Skia from 09b1b810850a to 2c25efd2e369 (9 revisions) (flutter/flutter#191470) 2026-08-21 [email protected] [Impeller] fix position of cached single glyph text shadows (flutter/flutter#191325) 2026-08-21 [email protected] Roll Skia from abdf8821f313 to 09b1b810850a (15 revisions) (flutter/flutter#191458) 2026-08-21 [email protected] Document that programmatic TextEditingController changes do not run input formatters (flutter/flutter#190166) 2026-08-21 [email protected] Adds new gallery benchmarks to windows (skia and impeller) (flutter/flutter#191454) 2026-08-21 [email protected] iOS: Deprecate FlutterEngine.isGpuDisabled (flutter/flutter#191393) 2026-08-21 [email protected] Revert: [web] Unskip decoration image lerp tests (flutter/flutter#191462) 2026-08-20 [email protected] android_hardware_smoke_test: Improve reliability (flutter/flutter#191374) 2026-08-20 [email protected] Don't size or offset the Android platform view before it is laid out (flutter/flutter#190895) 2026-08-20 [email protected] [iOS][add2app] Skip building SwiftPM plugins when generating CocoaPods artifacts (flutter/flutter#190736) 2026-08-20 [email protected] Optimize JSONMessageCodec UTF-8 conversion (flutter/flutter#190529) 2026-08-20 [email protected] [FML] Replace deprecated wstring_convert with Win32 APIs (flutter/flutter#191394) 2026-08-20 [email protected] SliverFillRemaining extends beyond viewport size when fillOverscroll is true (flutter/flutter#191236) 2026-08-20 [email protected] [flutter_tools] Update argParser usageLineLength when --wrap-column is passed (flutter/flutter#191264) 2026-08-20 [email protected] [flutter_tools] Fix UNC path resolution in depfile parsing on Windows (flutter/flutter#191265) 2026-08-20 [email protected] [web] Unskip decoration image lerp tests (flutter/flutter#191426) 2026-08-20 [email protected] Do not inject 'type' and 'method' into service extension responses (flutter/flutter#190946) 2026-08-20 [email protected] [flutter_tools] Fix crash in symbolize command on stream error (flutter/flutter#191273) 2026-08-20 [email protected] [flutter_tools] Prevent deletion of shared native asset hooks outputs as stale (flutter/flutter#191272) 2026-08-20 [email protected] [flutter_tools] Support package wildcard assets in app pubspec (flutter/flutter#191266) 2026-08-20 [email protected] Add SliverClipRect and SliverClipRRect (flutter/flutter#179003) 2026-08-20 [email protected] [flutter_tools] Implement Diagnostics extension slice and doctor integration (flutter/flutter#191162) ...
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Description
When a preview group is collapsed and re-expanded in the Widget Previewer, descendant scrollables (which search ancestor elements for a
PageStorageKeywhen restoring scroll offset) inherit thePageStorageKeyfrom theExpansionTile. They then attempt to read theExpansionTile's boolean expansion state as a double, throwing aTypeError: true: type 'bool' is not a subtype of type 'double?'.This PR wraps the
ExpansionTilechildren in aPageStoragewidget with a newPageStorageBucket, preventing descendant scrollable widgets from inheriting theExpansionTile'sPageStorageKey.Related Issues
Fixes #191242
Tests