未定义不是expo本机项目中的对象global.performance.now。

Question

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我正在尝试使用expo命令运行这个应用程序。到目前为止一切都很顺利，但今天却是这样。

如有任何帮助，将不胜感激！)

这些是我的依赖关系

{
  "dependencies": {
    "@expo-google-fonts/manrope": "^0.2.0",
    "@expo-google-fonts/roboto": "^0.2.2",
    "@expo/react-native-action-sheet": "^3.12.0",
    "@flyerhq/react-native-link-preview": "^1.6.0",
    "@gorhom/bottom-sheet": "4",
    "@react-native-async-storage/async-storage": "~1.15.0",
    "@react-native-community/clipboard": "^1.5.1",
    "@react-native-community/hooks": "^2.8.1",
    "@react-native-community/masked-view": "^0.1.11",
    "@react-native-community/netinfo": "7.1.3",
    "@react-native-firebase/app": "^14.5.0",
    "@react-native-firebase/messaging": "^14.5.0",
    "@react-native-picker/picker": "2.2.1",
    "@react-navigation/core": "^6.1.1",
    "@react-navigation/material-top-tabs": "^6.0.6",
    "@react-navigation/native": "^6.0.6",
    "@react-navigation/native-stack": "^6.2.5",
    "@react-navigation/stack": "^6.1.1",
    "@stomp/stompjs": "^6.1.2",
    "@stripe/stripe-react-native": "0.2.3",
    "expo-linking": "~3.0.0",
    "expo-media-library": "~14.0.0",
    "expo-notifications": "~0.14.0",
    "expo-splash-screen": "~0.14.1",
    "expo-status-bar": "~1.2.0",
    "expo-updates": "~0.11.6",
    "expo-web-browser": "~10.1.0",
    "firebase": "^9.6.7",
    "firebase-admin": "^10.0.0",,
    "react": "17.0.1",
    "react-dom": "17.0.1",
    "react-native": "0.64.3",
    "react-native-actionsheet": "^2.4.2",
    "react-native-bottomsheet-reanimated": "^0.1.1",
    "react-native-gesture-handler": "~2.1.0",
    "react-native-hold-menu": "^0.1.1",
    "react-native-image-crop-picker": "^0.37.2",
    "react-native-image-picker": "^4.7.0",
    "react-native-image-resizer": "^1.4.5",
    "react-native-image-viewing": "^0.2.1",
    "react-native-ionicons": "^4.x",
    "react-native-keyboard-aware-scroll-view": "^0.9.5",
    "react-native-linear-gradient": "^2.5.6",
    "react-native-link-preview": "^1.4.2",
    "react-native-pager-view": "5.4.9",
    "react-native-parsed-text": "^0.0.22",
    "react-native-push-notification": "^8.1.1",
    "react-native-reanimated": "2.4.1",
    "react-native-safe-area-context": "^3.3.2",
    "react-native-screens": "~3.10.1",
    "react-native-sticky-parallax-header": "^0.4.1",
    "react-native-svg": "12.1.1",
    "react-native-svg-charts": "^5.4.0",
    "react-native-tab-view": "^3.1.1",
    "react-native-unimodules": "0.12.0",
    "react-native-vector-icons": "^9.0.0",
    "react-native-web": "0.17.1",
    "react-native-webview": "11.15.0",
    "react-navigation": "^4.4.4",
    "rn-fetch-blob": "^0.12.0",
    "socket.io-client": "^4.4.1",
    "sockjs-client": "1.4.0",
    "stompjs": "2.3.3",
    "text-encoding": "^0.7.0",
    "url": "^0.11.0",
    "watchman": "^1.0.0"
  }}

我试着改变了react的版本--原生恢复包，但仍然找不出问题。

Answer 1

我最近也有这个问题。我不完全确定为什么会发生这种情况，但你可以尝试通过尝试和错误来找出根本原因。对我来说，我在build文件夹中对所有对build的引用进行了全局查找，并在代码中注释掉了所有引用(它们都是来自build文件夹中的node_modules包的js文件)。一旦我尝试重新加载应用程序，我就会得到一条关于缺少引用或未定义变量的更详细的消息(因为我评论了调用global.performance.now的行)。在我的例子中，它最终位于react-native包中，特别是在createPerformanceLogger.js文件中。有趣的是，我能够在包中找到另一个文件，它实际上设置了这个对象这里。

因此，作为临时解决办法，我在require('../Core/setUpPerformance');导入语句中添加了一个createPerformanceLogger.js语句。这个解决了我的问题。显然，这不是很好，因为它需要修改构建文件。我所做的是在每次构建之后添加一个后构建步骤，以编程方式完成这个步骤，以避免手动完成此操作(也是，因此我将其作为post组装步骤添加到我的gradle.build.kts文件中)。在任何情况下，YMMV，但确定的根本原因，这种方式将有助于打开您在此期间，直到找到一个更长期的解决方案。

值得注意的是，我最终开始在我的react + react-native版本的package.json中玩，现在react-native包甚至没有捆绑在我的build输出中(我觉得这很奇怪)，但这意味着我不再需要解决办法。顺便说一句，如果您好奇的话，这里是我使用的react-native版本。