1323acd0bb
Summary: Pull Request resolved: https://github.com/facebook/react-native/pull/21304 If you cd into `~/fbsource/xplat/js/react-native-github` and run: ``` xcodebuild -project RNTester/RNTester.xcodeproj -scheme RNTester -configuration Release -sdk iphonesimulator -derivedDataPath RNTester/build -quiet ``` The command fails with the following error: ``` ➜ react-native-github xcodebuild -project RNTester/RNTester.xcodeproj -scheme RNTester -configuration Release -sdk iphonesimulator -derivedDataPath RNTester/build -quiet === BUILD TARGET RNTester OF PROJECT RNTester WITH CONFIGURATION Release === + DEST=/Users/ramanpreet/fbsource/xplat/js/react-native-github/RNTester/build/Build/Products/Release-iphonesimulator/RNTester.app + [[ Release = *Debug* ]] + [[ -n '' ]] + case "$CONFIGURATION" in + DEV=false +++ dirname /Users/ramanpreet/fbsource/xplat/js/react-native-github/RNTester/../scripts/react-native-xcode.sh ++ cd /Users/ramanpreet/fbsource/xplat/js/react-native-github/RNTester/../scripts/.. ++ pwd + REACT_NATIVE_DIR=/Users/ramanpreet/fbsource/xplat/js/react-native-github + cd /Users/ramanpreet/fbsource/xplat/js/react-native-github/../.. + '[' -z '' ']' + export NVM_DIR=/Users/ramanpreet/.nvm + NVM_DIR=/Users/ramanpreet/.nvm + [[ -s index.ios.js ]] + ENTRY_FILE=RNTester/js/RNTesterApp.ios.js + [[ -s /Users/ramanpreet/.nvm/nvm.sh ]] ++ command -v brew + [[ -x /usr/local/bin/brew ]] ++ brew --prefix nvm + [[ -s /usr/local/Cellar/nvm/0.33.11/nvm.sh ]] + [[ -x /Users/ramanpreet/.nodenv/bin/nodenv ]] ++ command -v brew + [[ -x /usr/local/bin/brew ]] ++ brew --prefix nodenv + [[ -x /usr/local/Cellar/nodenv/1.1.2/bin/nodenv ]] + '[' -z node ']' + '[' -z '' ']' + export CLI_PATH=/Users/ramanpreet/fbsource/xplat/js/react-native-github/local-cli/cli.js + CLI_PATH=/Users/ramanpreet/fbsource/xplat/js/react-native-github/local-cli/cli.js + '[' -z '' ']' + BUNDLE_COMMAND=bundle + [[ -z '' ]] + CONFIG_ARG= + type node + BUNDLE_FILE=/Users/ramanpreet/fbsource/xplat/js/react-native-github/RNTester/build/Build/Products/Release-iphonesimulator/RNTester.app/main.jsbundle + node /Users/ramanpreet/fbsource/xplat/js/react-native-github/local-cli/cli.js bundle --entry-file RNTester/js/RNTesterApp.ios.js --platform ios --dev false --reset-cache --bundle-output /Users/ramanpreet/fbsource/xplat/js/react-native-github/RNTester/build/Build/Products/Release-iphonesimulator/RNTester.app/main.jsbundle --assets-dest /Users/ramanpreet/fbsource/xplat/js/react-native-github/RNTester/build/Build/Products/Release-iphonesimulator/RNTester.app warning: the transform cache was reset. Loading dependency graph, done. Unable to resolve module `babel/runtime/helpers/classCallCheck` from `/Users/ramanpreet/fbsource/xplat/js/react-native-github/RNTester/js/RNTesterApp.ios.js`: Module `babel/runtime/helpers/classCallCheck` does not exist in the Haste module map This might be related to https://github.com/facebook/react-native/issues/4968 To resolve try the following: 1. Clear watchman watches: `watchman watch-del-all`. 2. Delete the `node_modules` folder: `rm -rf node_modules && npm install`. 3. Reset Metro Bundler cache: `rm -rf /tmp/metro-bundler-cache-*` or `npm start -- --reset-cache`. 4. Remove haste cache: `rm -rf /tmp/haste-map-react-native-packager-*`. Error: Unable to resolve module `babel/runtime/helpers/classCallCheck` from `/Users/ramanpreet/fbsource/xplat/js/react-native-github/RNTester/js/RNTesterApp.ios.js`: Module `babel/runtime/helpers/classCallCheck` does not exist in the Haste module map This might be related to https://github.com/facebook/react-native/issues/4968 To resolve try the following: 1. Clear watchman watches: `watchman watch-del-all`. 2. Delete the `node_modules` folder: `rm -rf node_modules && npm install`. 3. Reset Metro Bundler cache: `rm -rf /tmp/metro-bundler-cache-*` or `npm start -- --reset-cache`. 4. Remove haste cache: `rm -rf /tmp/haste-map-react-native-packager-*`. at ModuleResolver.resolveDependency (/Users/ramanpreet/fbsource/xplat/js/react-native-github/node_modules/metro/src/node-haste/DependencyGraph/ModuleResolution.js:209:1301) at ResolutionRequest.resolveDependency (/Users/ramanpreet/fbsource/xplat/js/react-native-github/node_modules/metro/src/node-haste/DependencyGraph/ResolutionRequest.js:83:16) at DependencyGraph.resolveDependency (/Users/ramanpreet/fbsource/xplat/js/react-native-github/node_modules/metro/src/node-haste/DependencyGraph.js:238:485) at Object.resolve (/Users/ramanpreet/fbsource/xplat/js/react-native-github/node_modules/metro/src/lib/transformHelpers.js:180:25) at dependencies.map.result (/Users/ramanpreet/fbsource/xplat/js/react-native-github/node_modules/metro/src/DeltaBundler/traverseDependencies.js:311:29) at Array.map (<anonymous>) at resolveDependencies (/Users/ramanpreet/fbsource/xplat/js/react-native-github/node_modules/metro/src/DeltaBundler/traverseDependencies.js:307:16) at /Users/ramanpreet/fbsource/xplat/js/react-native-github/node_modules/metro/src/DeltaBundler/traverseDependencies.js:164:33 at Generator.next (<anonymous>) at step (/Users/ramanpreet/fbsource/xplat/js/react-native-github/node_modules/metro/src/DeltaBundler/traverseDependencies.js:266:307) + [[ false != true ]] + [[ ! -f /Users/ramanpreet/fbsource/xplat/js/react-native-github/RNTester/build/Build/Products/Release-iphonesimulator/RNTester.app/main.jsbundle ]] + echo 'error: File /Users/ramanpreet/fbsource/xplat/js/react-native-github/RNTester/build/Build/Products/Release-iphonesimulator/RNTester.app/main.jsbundle does not exist. This must be a bug with' error: File /Users/ramanpreet/fbsource/xplat/js/react-native-github/RNTester/build/Build/Products/Release-iphonesimulator/RNTester.app/main.jsbundle does not exist. This must be a bug with + echo 'React Native, please report it here: https://github.com/facebook/react-native/issues' React Native, please report it here: https://github.com/facebook/react-native/issues + exit 2 ** BUILD FAILED ** ``` Basically, we're missing the `babel/runtime/helpers/classCallCheck` function. Installing `babel/runtime` fixed the issue. Reviewed By: mjesun Differential Revision: D10021475 fbshipit-source-id: 3709bedb2fdaf552fa8c620c3515a5bc68deb771
React Native · 
Learn once, write anywhere: Build mobile apps with React.
See the official React Native website for an introduction to React Native.
Requirements
Supported target operating systems are >= Android 4.1 (API 16) and >= iOS 9.0. You may use Windows, macOS, or Linux as your development operating system, though building and running iOS apps is limited to macOS by default (tools like Expo can be used to get around this).
Building your first React Native app
Follow the Getting Started guide. The recommended way to install React Native depends on your project. Here you can find short guides for the most common scenarios:
How React Native works
React Native lets you build mobile apps using JavaScript. It uses the same design as React, letting you compose a rich mobile UI from declarative components.
With React Native, you don't build a "mobile web app", an "HTML5 app", or a "hybrid app". You build a real mobile app that's indistinguishable from an app built using Objective-C, Java, Kotlin, or Swift. React Native uses the same fundamental UI building blocks as regular iOS and Android apps. You just put those building blocks together using JavaScript and React.
React Native lets you build your app faster. Instead of recompiling, you can reload your app instantly. With hot reloading, you can even run new code while retaining your application state.
React Native combines smoothly with components written in Objective-C, Java, Kotlin, or Swift. It's simple to drop down to native code if you need to optimize a few aspects of your application. It's also easy to build part of your app in React Native, and part of your app using native code directly - that's how the Facebook app works.
The focus of React Native is on developer efficiency across all the platforms you care about - learn once, write anywhere. Facebook uses React Native in multiple production apps and will continue investing in React Native.
Full documentation
The full documentation for React Native can be found on our website. The source for the React Native documentation and website is hosted on a separate repo, https://github.com/facebook/react-native-website.
The React Native documentation only discusses the components, APIs, and topics specific to React Native (React on iOS and Android). For further documentation on the React API that is shared between React Native and React DOM, refer to the React documentation.
Join the React Native community
- Website: https://facebook.github.io/react-native
- Twitter: https://twitter.com/reactnative
- Discussion: https://discuss.reactjs.org/
See the CONTRIBUTING file for how to help out.
License
React Native is MIT licensed, as found in the LICENSE file.
React Native documentation is Creative Commons licensed, as found in the LICENSE-docs file.