RCTFatalException (#22532)
Summary: Fixes #22530 As described in the issue, the previous behavior for the `RCTFatal` macro was to truncate the `reason` on the resulting `NSException` to 75 characters. This would ensure the reason would fit on a single line, but resulted in issues debugging errors that occurred in the wild, as many crash logging tools (like Sentry) discard the `name` value of the exception and use the `reason` as their primary identifier. At 75 characters, useful information like the location of the error would usually be truncated. - [x] This extends the truncation threshold to 175 characters, which should be short enough to prevent full-screen-takeover length errors, but long enough to provide useful context to the error. - [x] This adds a `userInfo` value to the resulting `NSException`. It copies over the `userInfo` from the `NSError` passed to the macro, and adds an "untruncated message" value that contains the untruncated version of the `NSException`'s reason. [iOS] [Changed] - RCTFatalExceptions now include more information in their reason and a userInfo. <!-- CATEGORY may be: - [General] - [iOS] - [Android] TYPE may be: - [Added] for new features. - [Changed] for changes in existing functionality. - [Deprecated] for soon-to-be removed features. - [Removed] for now removed features. - [Fixed] for any bug fixes. - [Security] in case of vulnerabilities. For more detail, see https://keepachangelog.com/en/1.0.0/#how MESSAGE may answer "what and why" on a feature level. Use this to briefly tell React Native users about notable changes. EXAMPLES: [General] [Added] - Add snapToOffsets prop to ScrollView component [General] [Fixed] - Fix various issues in snapToInterval on ScrollView component [iOS] [Fixed] - Fix crash in RCTImagePicker --> Pull Request resolved: https://github.com/facebook/react-native/pull/22532 Differential Revision: D13373469 Pulled By: cpojer fbshipit-source-id: ac140d14ce76e1664869437c2c178bdd65ab6e0e
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. You can learn more about our open source roadmap in this blog post: Open Source Roadmap.
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. Releases are discussed in the React Native Community, https://github.com/react-native-community/react-native-releases, and larger discussions and proposals are in https://github.com/react-native-community/discussions-and-proposals.
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
- Help: https://facebook.github.io/react-native/en/help
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.