8206e841d1
Summary: Don't ask. Really, all those descriptions from official docs like below are useless: * `__bridge_transfer` Moves a Core Foundation pointer to Objective-C with transfer of the ownership to ARC. * `__bridge` Transfers a pointer between Objective-C and Core Foundation with no transfer of ownership All that is totally confusing and useless. At the end of the day, we only have to think about which additional `CFRetain` and `CFRelease` ARC will add or will not add for our pointers. So, following official docs recommendation, we would like to add `__bridge_transfer` because of course, we do want to ARC managing the variable after we introduced it to ARC here. But we also want to have shared ownership of this. That's the key. If we use `__bridge_transfer` ARC will assume that this variable already retained once (because it exists) and will call CFRelease at the end of the scope. Right before that when we pass this variable down to call stack ARC will retain and then manage the variable according to the rest of the code. But still, from this point, we will have zero-balanced reference counter; the owning by `shared_ptr` bump is already compensated with `CFRelease` at the end of the scope. As soon as the rest of the code release the object, it will be incorrectly deallocated. So, instead of using `__bridge_transfer` we have to use `__bridge`. That will indicate that *in this block* ARC does not manage the reference counter of the variable (which is kinda true because having `shared_ptr` inside the block already retains that) and will not add `CFRelease` at the end of the block. Reviewed By: mdvacca Differential Revision: D10054241 fbshipit-source-id: 6e82c5270fe5d53f1ed68e167b94f70dc4367a9f
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.