錯(cuò)誤內(nèi)容如下：
======== Exception caught by widgets library =======================================================
The following assertion was thrown building _CupertinoTextSelectionControlsToolbar(dirty, dependencies: [MediaQuery, _LocalizationsScope-[GlobalKey#1fa5b]], state: _CupertinoTextSelectionControlsToolbarState#23a43):
No CupertinoLocalizations found.
_CupertinoTextSelectionControlsToolbar widgets require CupertinoLocalizations to be provided by a Localizations widget ancestor.
The cupertino library uses Localizations to generate messages, labels, and abbreviations.
To introduce a CupertinoLocalizations, either use a CupertinoApp at the root of your application to include them automatically, or add a Localization widget with a CupertinoLocalizations delegate.
The specific widget that could not find a CupertinoLocalizations ancestor was: _CupertinoTextSelectionControlsToolbar
? dirty
? dependencies: [MediaQuery, _LocalizationsScope-[GlobalKey#1fa5b]]
? state: _CupertinoTextSelectionControlsToolbarState#23a43
The ancestors of this widget were:
? : CupertinoApp
? ? state: _CupertinoAppState#5e387
? : MyApp
? : ChangeNotifierProvider<KitUser>
? ? value: <not yet loaded>
? : MultiProvider
? ...
The relevant error-causing widget was:
? CupertinoApp CupertinoApp:file:///Users/jarvis/Desktop/Flutter-workspace/flutter_oa/code/oa/lib/main.dart:70:14
When the exception was thrown, this was the stack:
#0? ? ? debugCheckHasCupertinoLocalizations.<anonymous closure> (package:flutter/src/cupertino/debug.dart:23:7)
#1? ? ? debugCheckHasCupertinoLocalizations (package:flutter/src/cupertino/debug.dart:43:4)
#2? ? ? CupertinoLocalizations.of (package:flutter/src/cupertino/localizations.dart:262:12)
#3? ? ? _CupertinoTextSelectionControlsToolbarState.build (package:flutter/src/cupertino/text_selection.dart:135:73)
#4? ? ? StatefulElement.build (package:flutter/src/widgets/framework.dart:4782:27)
#5? ? ? ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:4665:15)
#6? ? ? StatefulElement.performRebuild (package:flutter/src/widgets/framework.dart:4840:11)
#7? ? ? Element.rebuild (package:flutter/src/widgets/framework.dart:4355:5)
#8? ? ? ComponentElement._firstBuild (package:flutter/src/widgets/framework.dart:4643:5)
#9? ? ? StatefulElement._firstBuild (package:flutter/src/widgets/framework.dart:4831:11)
#10? ? ComponentElement.mount (package:flutter/src/widgets/framework.dart:4638:5)
...? ? Normal element mounting (39 frames)
#49? ? Element.inflateWidget (package:flutter/src/widgets/framework.dart:3673:14)
#50? ? MultiChildRenderObjectElement.inflateWidget (package:flutter/src/widgets/framework.dart:6333:36)
#51? ? Element.updateChild (package:flutter/src/widgets/framework.dart:3425:18)
#52? ? RenderObjectElement.updateChildren (package:flutter/src/widgets/framework.dart:5758:32)
#53? ? MultiChildRenderObjectElement.update (package:flutter/src/widgets/framework.dart:6356:17)
#54? ? Element.updateChild (package:flutter/src/widgets/framework.dart:3412:15)
#55? ? ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:4690:16)
#56? ? StatefulElement.performRebuild (package:flutter/src/widgets/framework.dart:4840:11)
#57? ? Element.rebuild (package:flutter/src/widgets/framework.dart:4355:5)
#58? ? BuildOwner.buildScope (package:flutter/src/widgets/framework.dart:2620:33)
#59? ? WidgetsBinding.drawFrame (package:flutter/src/widgets/binding.dart:882:21)
#60? ? RendererBinding._handlePersistentFrameCallback (package:flutter/src/rendering/binding.dart:319:5)
#61? ? SchedulerBinding._invokeFrameCallback (package:flutter/src/scheduler/binding.dart:1143:15)
#62? ? SchedulerBinding.handleDrawFrame (package:flutter/src/scheduler/binding.dart:1080:9)
#63? ? SchedulerBinding._handleDrawFrame (package:flutter/src/scheduler/binding.dart:996:5)
#67? ? _invoke (dart:ui/hooks.dart:166:10)
#68? ? PlatformDispatcher._drawFrame (dart:ui/platform_dispatcher.dart:270:5)
#69? ? _drawFrame (dart:ui/hooks.dart:129:31)
(elided 3 frames from dart:async)
====================================================================================================
從上面的錯(cuò)誤信息中的一句：
To introduce a CupertinoLocalizations, either use a CupertinoApp at the root of your application to include them automatically, or add a Localization widget with a CupertinoLocalizations delegate.?
大致的意思是需要引用‘CupertinoLocalizations’這么個(gè)東西，然后用’CupertinoApp‘這個(gè)東西包裹，那么‘CupertinoLocalizations’需要放在那里呢，哎，就是放在語(yǔ)言代理的‘localizationsDelegates’位置下，
當(dāng)然，不能直接使用‘CupertinoLocalizations’，不然也是報(bào)錯(cuò)，這里需要使用的是‘GlobalCupertinoLocalizations.delegate,’，這個(gè)代理，我這里是區(qū)分了iOS和android設(shè)備平臺(tái)。
具體可參考下圖：
