在首次使用Dart/Flutter时,我创建了一个非常简单的演示应用程序,其中包含Drawer. 该应用程序在Android 模拟器中编译并启动,但不久后就中止并显示错误消息Null check operator used on a null value。在 之外Drawer,本地化工作完美无缺。
我到底做错了什么以及如何解决?
\n版本:
\nFlutter 2.2.0 \xe2\x80\xa2 channel stable \xe2\x80\xa2 https://github.com/flutter/flutter.git\nFramework \xe2\x80\xa2 revision b22742018b (12 days ago) \xe2\x80\xa2 2021-05-14 19:12:57 -0700\nEngine \xe2\x80\xa2 revision a9d88a4d18\nTools \xe2\x80\xa2 Dart 2.13.0\nRun Code Online (Sandbox Code Playgroud)\nGitHub 上提供了该应用程序的完整源代码:https://github.com/DarkPurpleKnight/null_issue
\n主要.dart:
\nimport \'package:flutter/material.dart\';\nimport \'package:flutter_localizations/flutter_localizations.dart\';\nimport \'package:flutter_gen/gen_l10n/app_localizations.dart\';\n\n\nvoid main() {\n runApp(NullIssueApp());\n}\n\nclass NullIssueApp extends StatelessWidget {\n @override\n Widget build(BuildContext context) {\n return MaterialApp(\n title: \'Null issue\',\n localizationsDelegates: [\n AppLocalizations.delegate,\n GlobalMaterialLocalizations.delegate,\n …Run Code Online (Sandbox Code Playgroud)