我有不变冲突：本机模块不能为null错误，下面是第二个错误。我在网上发现这个问题可能与模块目录中没有ios文件夹有关，我在本地系统和github上查看了每个文件夹，其中都包含ios文件夹
{
"main": "index.js",
"scripts": {
"android": "expo run:android",
"ios": "expo run:ios",
"web": "expo start --web",
"start": "expo start --dev-client"
},
"dependencies": {
"@invertase/react-native-apple-authentication": "^2.1.5",
"@react-native-community/clipboard": "^1.5.1",
"@react-native-community/datetimepicker": "4.0.0",
"@react-native-google-signin/google-signin": "^7.0.1",
"@react-native-picker/picker": "2.2.1",
"@react-navigation/bottom-tabs": "^6.0.9",
"@react-navigation/drawer": "^6.1.8",
"@react-navigation/native": "^6.0.6",
"@react-navigation/native-stack": "^6.2.5",
"expo": "^44.0.0",
"expo-file-system": "~13.1.0",
"expo-splash-screen": "~0.14.1",
"expo-status-bar": "~1.2.0",
"expo-updates": "~0.11.3",
"from": "^0.1.7",
"react": "^17.0.2",
"react-dom": "17.0.1",
"react-native": "^0.66.4",
"react-native-biometrics": "^2.1.4",
"react-native-canvas": "^0.1.38",
"react-native-chart-kit": "^6.11.0",
"react-native-chartjs": "^1.0.3",
"react-native-document-picker": "^7.1.1",
"react-native-fbsdk": "^3.0.0",
"react-native-file-access": "^2.1.0",
"react-native-flash-message": "^0.2.0",
"react-native-gesture-handler": "~2.1.0",
"react-native-gifted-charts": "^0.2.2",
"react-native-git-upgrade": "^0.2.7",
"react-native-haptic-feedback": "^1.13.0",
"react-native-image-picker": "^4.4.2",
"react-native-image-viewing": "^0.2.1",
"react-native-ios-context-menu": "^1.7.0",
"react-native-keyboard-accessory": "^0.1.16",
"react-native-keyboard-aware-scroll-view": "^0.9.5",
"react-native-keychain": "^8.0.0",
"react-native-linear-gradient": "^2.5.6",
"react-native-mmkv": "^1.5.4",
"react-native-paper": "^4.10.1",
"react-native-paper-dates": "^0.8.0",
"react-native-picker-select": "^8.0.4",
"react-native-qrcode-svg": "^6.1.2",
"react-native-reanimated": "~2.3.1",
"react-native-safe-area-context": "3.3.2",
"react-native-screens": "~3.10.1",
"react-native-svg": "12.1.1",
"react-native-swipe-gestures": "^1.0.5",
"react-native-vector-icons": "^9.0.0",
"react-native-view-pdf": "^0.12.2",
"react-native-web": "0.17.1",
"react-native-webview": "11.15.0"
},
"devDependencies": {
"@babel/core": "^7.12.9",
"babel-plugin-transform-remove-console": "^6.9.4"
},
"private": true,
"name": "MyApp",
"version": "1.0.0",
"expo": {
"autolinking": {
"exclude": [
"expo-file-system",
"expo-updates"
]
}
}
}
Invariant Violation: "main" has not been registered. This can happen if:
- Metro(本地开发服务器(从错误的文件夹中运行。检查Metro是否正在运行，在当前项目中停止并重新启动它
- 由于出现错误，模块加载失败，未调用
AppRegistry.registerComponent
我仔细查看https://reactnative.dev/docs/libraries和stackoverflow。我进行了npx-pod安装和npx-react本机运行ios，但返回时出现了相同的错误。
index.js
import { registerRootComponent } from 'expo';
import App from './App';
// registerRootComponent calls AppRegistry.registerComponent('main', () => App);
// It also ensures that whether you load the app in Expo Go or in a native build,
// the environment is set up appropriately
registerRootComponent(App);
如有任何帮助，将不胜感激
**编辑-2022年1月20日
我终于通过更改解决了这个问题
module.exports = function(api) {
api.cache(true);
return {
presets: ['module:metro-react-native-babel-preset']
};
}；
至
module.exports = function(api) {
api.cache(true);
return {
presets: ['module:metro-react-native-babel-preset'],
plugins: ['react-native-reanimated/plugin']
};
};
分别检查库@react-navigation/drawer与IOS和Android的兼容性，手动链接，有时自动链接不起作用。确保您正在运行正确的项目，清理构建和安装pod并检查它。