我想用 Flutter 构建一个数学应用程序。应该有基本的功能。但是,我面临以下问题:当我的计时器耗尽并且我被定向到下一页时,会出现以下错误消息:
\n完成小部件树时抛出以下断言:\n查找已停用小部件的祖先是不安全的。
\n此时小部件的元素树的状态不再稳定。
\n要在 widget 的 dispose() 方法中安全地引用它的祖先,请通过在 widget 的 didChangeDependency() 方法中调用 dependentOnInheritedWidgetOfExactType() 来保存对祖先的引用。
\nclass MathFunctionScreen extends StatefulWidget {\n static String id = "MathFunctionScreen";\n const MathFunctionScreen({Key? key}) : super(key: key);\n @override\n State<MathFunctionScreen> createState() => _MathFunctionScreenState();\n}\n\nclass _MathFunctionScreenState extends State<MathFunctionScreen>\n with TickerProviderStateMixin {\n DataBase db = DataBase();\n late int myTime;\n late int timeStamp;\n @override\n void initState() {\n print("initState() wurde ausgef\xc3\xbchrt");\n Provider.of<NumberGenerator>(context, listen: false).ctrl;\n myOnChange();\n Provider.of<NumberGenerator>(context, listen: false).mathCorrectAnswer;\n Provider.of<NumberGenerator>(context, listen: false).operator;\n Provider.of<NumberGenerator>(context, listen: false).setDatabase();\n Provider.of<TimerProvider>(context, listen: false).startTimer(context);\n …Run Code Online (Sandbox Code Playgroud) 当我尝试在 iPhone 14 Pro Max 模拟器上运行 Flutter 应用程序时,收到以下错误消息:
\nCocoaPods' output:\n\xe2\x86\xb3\n Preparing\n\n Analyzing dependencies\n\n Inspecting targets to integrate\n Using `ARCHS` setting to build architectures of target `Pods-Runner`: (``)\n [!] Unable to find a target named `RunnerTests` in project `Runner.xcodeproj`, did find `Runner`.\n\n \nError running pod install\nError launching application on iPhone 14 Pro Max.\nRun Code Online (Sandbox Code Playgroud)\n我的 Podfile 看起来像这样:
\n platform :ios, '13.0'\n\n# CocoaPods analytics sends network stats synchronously affecting flutter build latency.\nENV['COCOAPODS_DISABLE_STATS'] = 'true'\n\nproject 'Runner', {\n 'Debug' => :debug,\n 'Profile' => …Run Code Online (Sandbox Code Playgroud)