Fix internal Flutter error scrolling doc while width constrained

``` ══╡ EXCEPTION CAUGHT BY SCHEDULER LIBRARY ╞═════════════════════════════════════════════════════════ The following assertion was thrown during a scheduler callback: Layer OffsetEngineLayer was previously used as oldLayer. Once a layer is used as oldLayer, it may not be used again. Instead, after calling one of the SceneBuilder.push* methods and passing an oldLayer to it, use the layer returned by the method as oldLayer in subsequent frames. 'dart:ui/compositing.dart': Failed assertion: line 110 pos 9: '<optimized out>' 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 When the exception was thrown, this was the stack: #2 _EngineLayerWrapper._debugCheckNotUsedAsOldLayer (dart:ui/compositing.dart:110:9) #3 SceneBuilder.addRetained.<anonymous closure>.recursivelyCheckChildrenUsedOnce (dart:ui/compositing.dart:695:21) #4 List.forEach (dart:core-patch/growable_array.dart:416:8) #5 SceneBuilder.addRetained.<anonymous closure>.recursivelyCheckChildrenUsedOnce (dart:ui/compositing.dart:701:18) #6 SceneBuilder.addRetained.<anonymous closure> (dart:ui/compositing.dart:704:7) #7 SceneBuilder.addRetained (dart:ui/compositing.dart:707:6) #8 Layer._addToSceneWithRetainedRendering (package:flutter/src/rendering/layer.dart:671:15) #9 ContainerLayer.addChildrenToScene (package:flutter/src/rendering/layer.dart:1284:13) #10 OffsetLayer.addToScene (package:flutter/src/rendering/layer.dart:1421:5) #11 Layer._addToSceneWithRetainedRendering (package:flutter/src/rendering/layer.dart:674:5) #12 ContainerLayer.addChildrenToScene (package:flutter/src/rendering/layer.dart:1284:13) #13 ClipRectLayer.addToScene (package:flutter/src/rendering/layer.dart:1590:5) #14 Layer._addToSceneWithRetainedRendering (package:flutter/src/rendering/layer.dart:674:5) #15 ContainerLayer.addChildrenToScene (package:flutter/src/rendering/layer.dart:1284:13) #16 OffsetLayer.addToScene (package:flutter/src/rendering/layer.dart:1421:5) #17 Layer._addToSceneWithRetainedRendering (package:flutter/src/rendering/layer.dart:674:5) #18 ContainerLayer.addChildrenToScene (package:flutter/src/rendering/layer.dart:1284:13) #19 OffsetLayer.addToScene (package:flutter/src/rendering/layer.dart:1421:5) #20 Layer._addToSceneWithRetainedRendering (package:flutter/src/rendering/layer.dart:674:5) #21 ContainerLayer.addChildrenToScene (package:flutter/src/rendering/layer.dart:1284:13) #22 OffsetLayer.addToScene (package:flutter/src/rendering/layer.dart:1421:5) #23 Layer._addToSceneWithRetainedRendering (package:flutter/src/rendering/layer.dart:674:5) #24 ContainerLayer.addChildrenToScene (package:flutter/src/rendering/layer.dart:1284:13) #25 TransformLayer.addToScene (package:flutter/src/rendering/layer.dart:1914:5) #26 ContainerLayer.buildScene (package:flutter/src/rendering/layer.dart:1097:5) #27 RenderView.compositeFrame (package:flutter/src/rendering/view.dart:231:37) #28 RendererBinding.drawFrame (package:flutter/src/rendering/binding.dart:514:18) #29 WidgetsBinding.drawFrame (package:flutter/src/widgets/binding.dart:869:13) #30 RendererBinding._handlePersistentFrameCallback (package:flutter/src/rendering/binding.dart:375:5) #31 SchedulerBinding._invokeFrameCallback (package:flutter/src/scheduler/binding.dart:1271:15) #32 SchedulerBinding.handleDrawFrame (package:flutter/src/scheduler/binding.dart:1200:9) #33 SchedulerBinding._handleDrawFrame (package:flutter/src/scheduler/binding.dart:1058:5) #34 _invoke (dart:ui/hooks.dart:145:13) #35 PlatformDispatcher._drawFrame (dart:ui/platform_dispatcher.dart:338:5) #36 _drawFrame (dart:ui/hooks.dart:112:31) (elided 2 frames from class _AssertionError) ════════════════════════════════════════════════════════════════════════════════════════════════════ ```
amake · Oct 12, 2022 · b93803a · b93803a
1 parent 59c7eb5
commit b93803a
Showing 1 changed file with 13 additions and 13 deletions.
diff --git a/lib/src/pages/document.dart b/lib/src/pages/document.dart
@@ -315,16 +315,19 @@ class _DocumentPageState extends State<DocumentPage> with ViewSettingsState {
       ? SliverPadding(padding: _kBigScreenDocumentPadding, sliver: child)
       : child;
 
-  Widget _maybeConstrainWidth(BuildContext context, {required Widget child}) =>
-      fullWidth
-          ? child
-          : Center(
-              child: ConstrainedBox(
-                constraints:
-                    BoxConstraints(maxWidth: _maxAllowedWidth(context)),
-                child: child,
-              ),
-            );
+  Widget _maybeConstrainWidth(BuildContext context, {required Widget child}) {
+    if (fullWidth || !_bigScreen || !_allowFullScreen(context)) {
+      return child;
+    }
+    final inset = (_screenWidth -
+            _maxRecommendedWidth(context) -
+            _kBigScreenDocumentPadding.left) /
+        2;
+    return Padding(
+      padding: EdgeInsets.symmetric(horizontal: inset),
+      child: child,
+    );
+  }
 
   bool _allowFullScreen(BuildContext context) =>
       _maxRecommendedWidth(context) +
@@ -335,9 +338,6 @@ class _DocumentPageState extends State<DocumentPage> with ViewSettingsState {
           16 <
       _screenWidth;
 
-  double _maxAllowedWidth(BuildContext context) =>
-      fullWidth ? _screenWidth : _maxRecommendedWidth(context);
-
   // Calculate the maximum document width as 72 of the character 'M' with the
   // user's preferred font size and family
   double _maxRecommendedWidth(BuildContext context) {