wildfly-28 相关问题


导入DecompressionStream模块

在我的 React Typescript 应用程序中,我收到此错误。 webpack 编译时出现 1 个警告 src/App.tsx 中出现错误:30:21 TS2304:找不到名称“DecompressionStream”。 28 | 28 const enc = new TextEncoder()...


如何使用具有列表列表值的字典从 Bigquery 中的表进行查询

我有一个bigquery表如下 idx 信息 1 {'columns':['name','age'], data:[['Sheldon', 29], ['Raj',28]]} 2 {'columns':['姓名','年龄'], 数据:[['伦纳德', 28], ['霍华德',29]]} 信息是一个字符串


“在‘redux’中找不到导出‘createStore’

./node_modules/@redux-saga/core/dist/redux-saga-core.esm.js 中的警告 1343:21-28 “在‘redux’中找不到导出‘compose’ @ ./node_modules/redux-saga/dist/redux-saga-core-npm-proxy.esm.js ...


尽可能快地进行嵌套循环

spatial_data = [[1,2,3,4,5,6], ....., [1,2,3,4,50,60]] #长度1000万 参考 = [[9, 39, 22, 28, 25, 5], ...... , [5, 16, 12, 34, 3, 9]] # 长度 100 对于参考中的 x: 结果 = [c 为...


VBA Like 运算符/正则表达式

在VBA中,匹配以下每个字符串的正则表达式是什么:56-...和...-28? 对于第二个,我尝试了以下方法,但没有成功: Target.Value 就像“[\.]{3}[\-]{1}[0-...


如何将 DMS 转换为给定格式的弧度:Python 中的 DD-MM-SS [已关闭]

我想知道如何将 DMS 从给定格式 DD-MM-SS 转换为弧度 这个“print (DMStoRAD(47-39-28))”的解应该是 0.831785 谢谢!


玩笑更新后无法读取未定义的属性“html”

对于使用 jest 的 Angular v12 项目,我刚刚将 jest 更新到版本 28。但是现在,我收到以下错误 失败 src/app/components/update-input/update-input.directive.spec.ts ● 测试套件


VBA 中包含点的正则表达式

在VBA中,匹配以下每个字符串的正则表达式是什么? 第一: 56-... 第二个: ...-28 对于第二个,我尝试了以下方法,但没有结果: 目标.值就像...


字符到日期的更改在数据框中产生“NA”

在数据框中,有一列以日期信息作为字符 str(mv$datum_mw) chr [1:6] “2012年11月15日” “2013年1月28日” “2014年8月12日” “2015年2月12日”...


如何在 UNITY Oculus Quest 2 和 Vive Focus 中获取 Android 设备序列号(在 Android 10 API 级别 28 上)

我需要序列号或类似的东西,因为我们公司创建 VR 应用程序,我创建必须在多个应用程序中识别特定设备的 Web API,因为我们


Qt 单元测试框架中的“0 次跳过,0 次列入黑名单”是什么意思?

当我运行 Qt 单元测试项目时,它以如下所示的摘要结束: 总计:28 次通过,1 次失败,0 次跳过,0 次列入黑名单 “通过”和“失败”类别很明显,但我...


如何按列而不是按行填充数组?

我需要制作一个 10 x 10 的二维数组,如下所示: 0 45 44 42 39 35 30 24 17 9 0 0 43 41 38 34 29 23 16 8 0 0 0 40 37 33 28 22 15 7 0 0 0 0 36 32 27 21 14 6 0 0 0 0 0 31 26 20 13 5 ...


带斜杠的边框半径在 React-pdf 中不起作用

我知道我们可以在CSS中为半圆设置border-radius: 4px/2px。 但它在 React pdf 中不起作用。 我尝试过这些。 我知道我们可以在CSS中为半圆设置border-radius: 4px/2px。 但它在 React pdf 中不起作用。 我尝试过这些。 你好 我导入了所有 React pdf 元素。但是当我尝试上述设计时,我在控制台中收到错误。 错误是 @react-pdf_renderer.js?v=e8b1cced:113701 Error: unsupported number: NaN at number2 (@react-pdf_renderer.js?v=e8b1cced:58798:11) at PDFDocument2.lineTo (@react-pdf_renderer.js?v=e8b1cced:59998:28) at clipNode2 (@react-pdf_renderer.js?v=e8b1cced:32924:7) at renderBackground3 (@react-pdf_renderer.js?v=e8b1cced:34087:5) at renderNode3 (@react-pdf_renderer.js?v=e8b1cced:34139:3) at renderChild2 (@react-pdf_renderer.js?v=e8b1cced:34123:12) at Array.forEach (<anonymous>) at renderChildren2 (@react-pdf_renderer.js?v=e8b1cced:34125:12) at renderNode3 (@react-pdf_renderer.js?v=e8b1cced:34145:5) at renderChild2 (@react-pdf_renderer.js?v=e8b1cced:34123:12) 有人可以帮忙吗 测试此类语法的最简单方法是在 repl 中https://react-pdf.org/repl 简短的回答是 4px/2 不是单个 px 值,因此 = NAN 使用任何其他单个愚蠢的数字即可。


在 HTML 文档中嵌入 TypeScript 代码

是否可以在网页中嵌入 TypeScript 代码?我想将 TypeScript 代码嵌入到脚本标签中,如下所示(以便它自动编译为 Javascript): <p>是否可以在网页中嵌入 TypeScript 代码?我想将 TypeScript 代码嵌入到脚本标签中,如下所示(以便它自动编译为 Javascript):</p> <pre><code>&lt;script type = &#34;text/typescript&#34;&gt; //TypeScript code goes here &lt;/script&gt; </code></pre> </question> <answer tick="true" vote="28"> <p>实际上有几个项目允许您使用类似的 TypeScript 代码 - <a href="https://github.com/niutech/typescript-compile" rel="noreferrer">TypeScript Compile</a>、<a href="https://github.com/ComFreek/ts-htaccess" rel="noreferrer">ts-htaccess</a>。</p> <p>这里的问题是 .ts 代码应该编译成 JavaScript - 它可以在客户端完成(速度慢;整个 TSC 也应该加载到客户端)或在服务器端完成(显然更快,而且它更快)在编译代码上利用缓存要容易得多)。</p> </answer> <answer tick="false" vote="18"> <p>这是我编写的版本,<strong>直接</strong>使用 Microsoft/TypeScript/master 的版本,因此它始终保持最新:<a href="https://github.com/basarat/typescript-script" rel="noreferrer">https://github.com/basarat/typescript-script</a></p> <p>您甚至可以将 <pre><code>ts</code></pre> 指向您可能拥有的任何其他 TypeScript 版本,它会正常工作 🌹</p> </answer> <answer tick="false" vote="6"> <p>已经为此目的开发了一个 JavaScript 库 - 它称为 <a href="https://github.com/niutech/typescript-compile" rel="noreferrer">TypeScript Compile</a>,它允许将 Typescript 嵌入到 HTML 中(如上所示。)</p> </answer> <answer tick="false" vote="0"> <p>我写这篇文章的目的是为了在浏览器中编译 TypeScript,以便我可以编写快速简单的示例来分享。</p> <p><a href="https://github.com/Sean-Bradley/text-typescript" rel="nofollow noreferrer">https://github.com/Sean-Bradley/text-typescript</a></p> <p>使用,</p> <pre><code>&lt;script type=&#34;text/typescript&#34;&gt; // Your TypeScript code here &lt;/script&gt; </code></pre> <p>并包含依赖项。</p> <pre><code>&lt;script src=&#34;https://cdn.jsdelivr.net/npm/<a href="/cdn-cgi/l/email-protection" data-cfemail="67131e17021404150e1713275249544954">[email protected]</a>&#34;&gt;&lt;/script&gt; &lt;script defer src=&#34;https://cdn.jsdelivr.net/npm/<a href="/cdn-cgi/l/email-protection" data-cfemail="3743524f431a434e47524454455e4743770619041907">[email protected]</a>&#34;&gt;&lt;/script&gt; </code></pre> <p>一个完整的示例,您可以复制/粘贴到 HTML 文档中并在本地尝试。</p> <pre><code>&lt;!DOCTYPE html&gt; &lt;html lang=&#34;en&#34;&gt; &lt;head&gt; &lt;meta charset=&#34;utf-8&#34; /&gt; &lt;meta name=&#34;viewport&#34; content=&#34;width=device-width, initial-scale=1&#34; /&gt; &lt;title&gt;&#34;text/typescript&#34; example&lt;/title&gt; &lt;meta name=&#34;description&#34; content=&#34;Transpiling and executing TypeScript in the browser&#34; /&gt; &lt;style&gt; body { overflow: hidden; margin: 0px; font-size: 15vw; } &lt;/style&gt; &lt;script type=&#34;text/typescript&#34;&gt; function foo(bar: string) { return &#34;Hello &#34; + bar; } let baz = &#34;World!&#34;; document.getElementById(&#34;root&#34;).innerHTML = foo(baz); &lt;/script&gt; &lt;script src=&#34;https://cdn.jsdelivr.net/npm/<a href="/cdn-cgi/l/email-protection" data-cfemail="13676a63766070617a636753263d203d20">[email protected]</a>&#34;&gt;&lt;/script&gt; &lt;script defer src=&#34;https://cdn.jsdelivr.net/npm/<a href="/cdn-cgi/l/email-protection" data-cfemail="ec98899498c198959c899f8f9e859c98acddc2dfc2dc">[email protected]</a>&#34;&gt;&lt;/script&gt; &lt;/head&gt; &lt;body&gt; &lt;div id=&#34;root&#34;&gt;&lt;/div&gt; &lt;/body&gt; &lt;/html&gt; </code></pre> <p>你可以看到它在这里、现在、今天发挥作用。</p> <p><a href="https://editor.sbcode.net/f1f4b5a73ec40283d1ddb37bb1e71f7e4e31b487" rel="nofollow noreferrer">https://editor.sbcode.net/f1f4b5a73ec40283d1ddb37bb1e71f7e4e31b487</a></p> </answer> </body></html>


错误:在此 BlocBuilder<InternetBloc> Widget<InternetBloc, InternetState> 上方找不到正确的提供程序

我在尝试将 flutter_bloc 集成到 flutter 项目中时遇到错误。 错误:在此 BlocBuilder 上方找不到正确的 Provider 我在尝试将 flutter_bloc 集成到 flutter 项目中时遇到错误。 错误:在此 BlocBuilder Widget 上方找不到正确的提供者 这是我正在使用的代码示例。 internet_state.dart abstract class InternetState{} class InitialInternetState extends InternetState{} class LostConnectionInternetState extends InternetState{} class GainConnectionInternetState extends InternetState{} internet_event.dart abstract class InternetEvent{} class LostConnectionEvent extends InternetEvent{} class GainConnectionEvent extends InternetEvent{} internet_bloc.dart class InternetBloc extends Bloc<InternetEvent, InternetState>{ final Connectivity _connectivity = Connectivity(); StreamSubscription? streamSubscription; InternetBloc() : super(InitialInternetState()){ on<GainConnectionEvent>((event, emit) => emit(GainConnectionInternetState())); on<LostConnectionEvent>((event, emit) => emit(LostConnectionInternetState())); _connectivity.onConnectivityChanged.listen((event) { if(event == ConnectivityResult.mobile || event == ConnectivityResult.wifi){ add(GainConnectionEvent()); } else { add(LostConnectionEvent()); } }); } @override Future<void> close() { streamSubscription?.cancel(); return super.close(); } } main.dart class MyApp extends StatelessWidget { const MyApp({super.key}); @override Widget build(BuildContext context) { return MaterialApp( title: 'Flutter Demo', theme: ThemeData( colorScheme: ColorScheme.fromSeed(seedColor: Colors.deepPurple), useMaterial3: true, ), home: const MyHomePage(title: 'Flutter Demo Home Page'), ); } } class MyHomePage extends StatelessWidget { const MyHomePage({super.key, required this.title}); final String title; @override Widget build(BuildContext context) { return Scaffold( appBar: AppBar(title: Text(title),), body: SafeArea( child: Center(child: BlocBuilder<InternetBloc, InternetState>( builder: (context, state) { return const Text("hello"); }, )), ),); } } 我明白了。 ======== 小部件库捕获异常====================================== =================== 构建 MediaQuery(MediaQueryData(size: Size(392.7, 783.3), devicePixelRatio: 2.8, textScaler: noscaling, platformBrightness: Brightness.light, padding: EdgeInsets.zero, viewPadding: EdgeInsets.zero, viewInsets: EdgeInsets 时抛出以下 ProviderNotFoundException。零,systemGestureInsets:EdgeInsets(29.8,24.0,29.8,8.0),alwaysUse24HourFormat:假,accessibleNavigation:假,highContrast:假,onOffSwitchLabels:假,disableAnimations:假,invertColors:假,boldText:假,navigationMode:传统,gestureSettings:DeviceGestureSettings (touchSlop:8.0),显示功能:[])): 错误:无法在此 BlocBuilder Widget 之上找到正确的提供程序 发生这种情况是因为您使用了不包含提供程序的 BuildContext 你的选择。有以下几种常见场景: 您在main.dart中添加了一个新的提供程序并执行了热重载。 要修复此问题,请执行热重启。 您尝试阅读的提供商处于不同的路线。 提供商具有“范围”。因此,如果您在路线中插入提供者,那么 其他路线将无法访问该提供商。 您使用了 BuildContext,它是您尝试读取的提供程序的祖先。 确保 BlocBuilder 位于您的 MultiProvider/Provider 下。 当您创建提供程序并尝试立即读取它时,通常会发生这种情况。 例如,代替: Widget build(BuildContext context) { return Provider<Example>( create: (_) => Example(), // Will throw a ProviderNotFoundError, because `context` is associated // to the widget that is the parent of `Provider<Example>` child: Text(context.watch<Example>().toString()), ); } 考虑使用builder,如下所示: Widget build(BuildContext context) { return Provider<Example>( create: (_) => Example(), // we use `builder` to obtain a new `BuildContext` that has access to the provider builder: (context, child) { // No longer throws return Text(context.watch<Example>().toString()); } ); } 如果这些解决方案都不起作用,请考虑在 StackOverflow 上寻求帮助: https://stackoverflow.com/questions/tagged/flutter The relevant error-causing widget was: SafeArea SafeArea:file:///Users/../Projects/flutterTest/bloc_test/lib/main.dart:37:13 When the exception was thrown, this was the stack: #0 Provider._inheritedElementOf (package:provider/src/provider.dart:343:7) #1 Provider.of (package:provider/src/provider.dart:293:30) #2 ReadContext.read (package:provider/src/provider.dart:649:21) #3 _BlocBuilderBaseState.initState (package:flutter_bloc/src/bloc_builder.dart:130:36) #4 StatefulElement._firstBuild (package:flutter/src/widgets/framework.dart:5602:55) #5 ComponentElement.mount (package:flutter/src/widgets/framework.dart:5447:5) ... Normal element mounting (4 frames) #9 Element.inflateWidget (package:flutter/src/widgets/framework.dart:4326:16) #10 Element.updateChild (package:flutter/src/widgets/framework.dart:3831:20) #11 ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:5496:16) #12 Element.rebuild (package:flutter/src/widgets/framework.dart:5187:7) #13 ProxyElement.update (package:flutter/src/widgets/framework.dart:5800:5) #14 Element.updateChild (package:flutter/src/widgets/framework.dart:3815:15) #15 SingleChildRenderObjectElement.update (package:flutter/src/widgets/framework.dart:6743:14) #16 Element.updateChild (package:flutter/src/widgets/framework.dart:3815:15) #17 ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:5496:16) #18 Element.rebuild (package:flutter/src/widgets/framework.dart:5187:7) #19 StatelessElement.update (package:flutter/src/widgets/framework.dart:5547:5) #20 Element.updateChild (package:flutter/src/widgets/framework.dart:3815:15) #21 ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:5496:16) #22 Element.rebuild (package:flutter/src/widgets/framework.dart:5187:7) #23 StatelessElement.update (package:flutter/src/widgets/framework.dart:5547:5) #24 Element.updateChild (package:flutter/src/widgets/framework.dart:3815:15) #25 ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:5496:16) #26 Element.rebuild (package:flutter/src/widgets/framework.dart:5187:7) #27 StatelessElement.update (package:flutter/src/widgets/framework.dart:5547:5) #28 Element.updateChild (package:flutter/src/widgets/framework.dart:3815:15) #29 ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:5496:16) #30 Element.rebuild (package:flutter/src/widgets/framework.dart:5187:7) #31 ProxyElement.update (package:flutter/src/widgets/framework.dart:5800:5) #32 Element.updateChild (package:flutter/src/widgets/framework.dart:3815:15) #33 ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:5496:16) #34 Element.rebuild (package:flutter/src/widgets/framework.dart:5187:7) #35 ProxyElement.update (package:flutter/src/widgets/framework.dart:5800:5) #36 Element.updateChild (package:flutter/src/widgets/framework.dart:3815:15) #37 Element.updateChildren (package:flutter/src/widgets/framework.dart:3964:32) #38 MultiChildRenderObjectElement.update (package:flutter/src/widgets/framework.dart:6896:17) #39 Element.updateChild (package:flutter/src/widgets/framework.dart:3815:15) #40 ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:5496:16) #41 Element.rebuild (package:flutter/src/widgets/framework.dart:5187:7) #42 ProxyElement.update (package:flutter/src/widgets/framework.dart:5800:5) #43 Element.updateChild (package:flutter/src/widgets/framework.dart:3815:15) #44 ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:5496:16) #45 StatefulElement.performRebuild (package:flutter/src/widgets/framework.dart:5634:11) #46 Element.rebuild (package:flutter/src/widgets/framework.dart:5187:7) #47 StatefulElement.update (package:flutter/src/widgets/framework.dart:5657:5) #48 Element.updateChild (package:flutter/src/widgets/framework.dart:3815:15) #49 ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:5496:16) #50 StatefulElement.performRebuild (package:flutter/src/widgets/framework.dart:5634:11) #51 Element.rebuild (package:flutter/src/widgets/framework.dart:5187:7) #52 StatefulElement.update (package:flutter/src/widgets/framework.dart:5657:5) #53 Element.updateChild (package:flutter/src/widgets/framework.dart:3815:15) #54 ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:5496:16) #55 Element.rebuild (package:flutter/src/widgets/framework.dart:5187:7) #56 ProxyElement.update (package:flutter/src/widgets/framework.dart:5800:5) #57 Element.updateChild (package:flutter/src/widgets/framework.dart:3815:15) #58 ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:5496:16) #59 StatefulElement.performRebuild (package:flutter/src/widgets/framework.dart:5634:11) #60 Element.rebuild (package:flutter/src/widgets/framework.dart:5187:7) #61 StatefulElement.update (package:flutter/src/widgets/framework.dart:5657:5) #62 Element.updateChild (package:flutter/src/widgets/framework.dart:3815:15) #63 SingleChildRenderObjectElement.update (package:flutter/src/widgets/framework.dart:6743:14) #64 Element.updateChild (package:flutter/src/widgets/framework.dart:3815:15) #65 ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:5496:16) #66 Element.rebuild (package:flutter/src/widgets/framework.dart:5187:7) #67 ProxyElement.update (package:flutter/src/widgets/framework.dart:5800:5) #68 Element.updateChild (package:flutter/src/widgets/framework.dart:3815:15) #69 SingleChildRenderObjectElement.update (package:flutter/src/widgets/framework.dart:6743:14) #70 Element.updateChild (package:flutter/src/widgets/framework.dart:3815:15) #71 ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:5496:16) #72 StatefulElement.performRebuild (package:flutter/src/widgets/framework.dart:5634:11) #73 Element.rebuild (package:flutter/src/widgets/framework.dart:5187:7) #74 StatefulElement.update (package:flutter/src/widgets/framework.dart:5657:5) #75 Element.updateChild (package:flutter/src/widgets/framework.dart:3815:15) #76 ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:5496:16) #77 StatefulElement.performRebuild (package:flutter/src/widgets/framework.dart:5634:11) #78 Element.rebuild (package:flutter/src/widgets/framework.dart:5187:7) #79 StatefulElement.update (package:flutter/src/widgets/framework.dart:5657:5) #80 Element.updateChild (package:flutter/src/widgets/framework.dart:3815:15) #81 ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:5496:16) #82 Element.rebuild (package:flutter/src/widgets/framework.dart:5187:7) #83 ProxyElement.update (package:flutter/src/widgets/framework.dart:5800:5) #84 Element.updateChild (package:flutter/src/widgets/framework.dart:3815:15) #85 ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:5496:16) #86 Element.rebuild (package:flutter/src/widgets/framework.dart:5187:7) #87 ProxyElement.update (package:flutter/src/widgets/framework.dart:5800:5) #88 Element.updateChild (package:flutter/src/widgets/framework.dart:3815:15) #89 ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:5496:16) #90 Element.rebuild (package:flutter/src/widgets/framework.dart:5187:7) #91 ProxyElement.update (package:flutter/src/widgets/framework.dart:5800:5) #92 Element.updateChild (package:flutter/src/widgets/framework.dart:3815:15) #93 ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:5496:16) #94 StatefulElement.performRebuild (package:flutter/src/widgets/framework.dart:5634:11) #95 Element.rebuild (package:flutter/src/widgets/framework.dart:5187:7) #96 StatefulElement.update (package:flutter/src/widgets/framework.dart:5657:5) #97 Element.updateChild (package:flutter/src/widgets/framework.dart:3815:15) #98 ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:5496:16) #99 Element.rebuild (package:flutter/src/widgets/framework.dart:5187:7) #100 ProxyElement.update (package:flutter/src/widgets/framework.dart:5800:5) #101 Element.updateChild (package:flutter/src/widgets/framework.dart:3815:15) #102 ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:5496:16) #103 StatefulElement.performRebuild (package:flutter/src/widgets/framework.dart:5634:11) #104 Element.rebuild (package:flutter/src/widgets/framework.dart:5187:7) #105 StatefulElement.update (package:flutter/src/widgets/framework.dart:5657:5) #106 Element.updateChild (package:flutter/src/widgets/framework.dart:3815:15) #107 ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:5496:16) #108 Element.rebuild (package:flutter/src/widgets/framework.dart:5187:7) #109 BuildOwner.buildScope (package:flutter/src/widgets/framework.dart:2895:19) #110 WidgetsBinding.drawFrame (package:flutter/src/widgets/binding.dart:984:21) #111 RendererBinding._handlePersistentFrameCallback (package:flutter/src/rendering/binding.dart:457:5) #112 SchedulerBinding._invokeFrameCallback (package:flutter/src/scheduler/binding.dart:1325:15) #113 SchedulerBinding.handleDrawFrame (package:flutter/src/scheduler/binding.dart:1255:9) #114 SchedulerBinding.scheduleWarmUpFrame.<anonymous closure> (package:flutter/src/scheduler/binding.dart:978:7) #118 _RawReceivePort._handleMessage (dart:isolate-patch/isolate_patch.dart:184:12) (elided 3 frames from class _Timer and dart:async-patch) ==================================================================================================== 我不想使用像 MultiProvider 这样的全局提供程序。 您应该在某处创建 InternetBloc 并提供它。 MultiProvider 本身并不是全局的,它只是多个。 更多信息在这里:https://bloclibrary.dev/#/flutterbloccoreconcepts?id=blocprovider 所以,如果您不想使用全局提供程序,它将看起来像这样: class MyHomePage extends StatelessWidget { const MyHomePage({super.key, required this.title}); final String title; @override Widget build(BuildContext context) { return Scaffold( appBar: AppBar( title: Text(title), ), body: SafeArea( child: Center( child: BlocProvider<InternetBloc>( create: ( context) => InternetBloc(), child: BlocBuilder<InternetBloc, InternetState>( builder: (context, state) { return const Text("hello"); }, ), ), ), ), ); } } 要使用 BlocBuilder,您需要在 Widget 树中放置一个 BlocProvider。最佳实践是将其放置得尽可能深。在您的情况下,只需将 BlocProvider 放在 BlocBuilder 之上。 此外 MultiProvider / MultiBlocProvider 不是全局 Provider。它只是一个提供多个 Provider/BlocProvider 的便捷小部件。 class MyHomePage extends StatelessWidget { const MyHomePage({super.key, required this.title}); final String title; @override Widget build(BuildContext context) { return Scaffold( appBar: AppBar( title: Text(title), ), body: SafeArea( child: Center( // Now everything below that can access the InternetBloc child: BlocProvider<InternetBloc>( create: (_) => InternetBloc(), child: BlocBuilder<InternetBloc, InternetState>( builder: (context, state) { return const Text("hello"); }, ), ), ), ), ); } }


© www.soinside.com 2019 - 2024. All rights reserved.