flutter - 在 Null-Safety Flutter 上构建期间调用的 setState() 或 markNeedsBuild()

Question

有人可以解释一下这个错误的含义以及如何解决它吗？

我在更新 null-safety 后得到了它，不知道如何修复它。

我已经在 stackoverflow 上检查了其他线程，但无法理解问题所在。也许有人可以以更好的方式向我解释。

每次我从主页切换到另一个页面时都会出现

setState() or markNeedsBuild() called during build.

This _InheritedProviderScope<JourneyProvider?> widget cannot be marked as needing to build because the framework is already in the process of building widgets.  A widget can be marked as needing to be built during the build phase only if one of its ancestors is currently building. This exception is allowed because the framework builds parent widgets before children, which means a dirty descendant will always be built. Otherwise, the framework might not visit this widget during this build phase.
The widget on which setState() or markNeedsBuild() was called was: _InheritedProviderScope<JourneyProvider?>
  value: Instance of 'JourneyProvider'
  listening to value
The widget which was currently being built when the offending call was made was: Builder
When the exception was thrown, this was the stack: 
#0      Element.markNeedsBuild.<anonymous closure> (package:flutter/src/widgets/framework.dart:4305:11)
#1      Element.markNeedsBuild (package:flutter/src/widgets/framework.dart:4320:6)
#2      _InheritedProviderScopeElement.markNeedsNotifyDependents (package:provider/src/inherited_provider.dart:570:5)
#3      ChangeNotifier.notifyListeners (package:flutter/src/foundation/change_notifier.dart:308:24)
#4      JourneyProvider.getMyJourney (package:PinkDrive/providers/journeyProvider.dart:303:5)
#5      MyJourneyState.initData (package:PinkDrive/views/journey/myJounrey.dart:55:58)
#6      MyJourneyState.initState (package:PinkDrive/views/journey/myJounrey.dart:49:9)
#7      StatefulElement._firstBuild (package:flutter/src/widgets/framework.dart:4805:57)
#8      ComponentElement.mount (package:flutter/src/widgets/framework.dart:4638:5)
...     Normal element mounting (169 frames)
#177    Element.inflateWidget (package:flutter/src/widgets/framework.dart:3673:14)
#178    MultiChildRenderObjectElement.inflateWidget (package:flutter/src/widgets/framework.dart:6333:36)
#179    Element.updateChild (package:flutter/src/widgets/framework.dart:3425:18)
#180    RenderObjectElement.updateChildren (package:flutter/src/widgets/framework.dart:5758:32)
#181    MultiChildRenderObjectElement.update (package:flutter/src/widgets/framework.dart:6356:17)
#182    Element.updateChild (package:flutter/src/widgets/framework.dart:3412:15)
#183    ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:4690:16)
#184    StatefulElement.performRebuild (package:flutter/src/widgets/framework.dart:4840:11)
#185    Element.rebuild (package:flutter/src/widgets/framework.dart:4355:5)
#186    StatefulElement.update (package:flutter/src/widgets/framework.dart:4872:5)
#187    Element.updateChild (package:flutter/src/widgets/framework.dart:3412:15)
#188    ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:4690:16)
#189    Element.rebuild (package:flutter/src/widgets/framework.dart:4355:5)
#190    ProxyElement.update (package:flutter/src/widgets/framework.dart:5020:5)
#191    Element.updateChild (package:flutter/src/widgets/framework.dart:3412:15)
#192    ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:4690:16)
#193    Element.rebuild (package:flutter/src/widgets/framework.dart:4355:5)
#194    ProxyElement.update (package:flutter/src/widgets/framework.dart:5020:5)
#195    _InheritedNotifierElement.update (package:flutter/src/widgets/inherited_notifier.dart:181:11)
#196    Element.updateChild (package:flutter/src/widgets/framework.dart:3412:15)
#197    SingleChildRenderObjectElement.update (package:flutter/src/widgets/framework.dart:6202:14)
#198    Element.updateChild (package:flutter/src/widgets/framework.dart:3412:15)
#199    ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:4690:16)
#200    StatefulElement.performRebuild (package:flutter/src/widgets/framework.dart:4840:11)
#201    Element.rebuild (package:flutter/src/widgets/framework.dart:4355:5)
#202    StatefulElement.update (package:flutter/src/widgets/framework.dart:4872:5)
#203    Element.updateChild (package:flutter/src/widgets/framework.dart:3412:15)
#204    SingleChildRenderObjectElement.update (package:flutter/src/widgets/framework.dart:6202:14)
#205    Element.updateChild (package:flutter/src/widgets/framework.dart:3412:15)
#206    SingleChildRenderObjectElement.update (package:flutter/src/widgets/framework.dart:6202:14)
#207    Element.updateChild (package:flutter/src/widgets/framework.dart:3412:15)
#208    ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:4690:16)
#209    Element.rebuild (package:flutter/src/widgets/framework.dart:4355:5)
#210    ProxyElement.update (package:flutter/src/widgets/framework.dart:5020:5)
#211    Element.updateChild (package:flutter/src/widgets/framework.dart:3412:15)
#212    ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:4690:16)
#213    StatefulElement.performRebuild (package:flutter/src/widgets/framework.dart:4840:11)
#214    Element.rebuild (package:flutter/src/widgets/framework.dart:4355:5)
#215    BuildOwner.buildScope (package:flutter/src/widgets/framework.dart:2620:33)
#216    WidgetsBinding.drawFrame (package:flutter/src/widgets/binding.dart:882:21)
#217    RendererBinding._handlePersistentFrameCallback (package:flutter/src/rendering/binding.dart:319:5)
#218    SchedulerBinding._invokeFrameCallback (package:flutter/src/scheduler/binding.dart:1143:15)
#219    SchedulerBinding.handleDrawFrame (package:flutter/src/scheduler/binding.dart:1080:9)
#220    SchedulerBinding._handleDrawFrame (package:flutter/src/scheduler/binding.dart:996:5)
#224    _invoke (dart:ui/hooks.dart:166:10)
#225    PlatformDispatcher._drawFrame (dart:ui/platform_dispatcher.dart:270:5)
#226    _drawFrame (dart:ui/hooks.dart:129:31)
(elided 3 frames from dart:async)
The JourneyProvider sending notification was: Instance of 'JourneyProvider'

标签： flutterdartnull-safety