Liam Jones
8f072b438a
Summary: Prior to 0.69, an RN app receiving the `UIApplicationDidReceiveMemoryWarningNotification` notification resulted in RN performing a GC on the JSC. Since 0.69 this has not worked, this PR fixes the issue. Before 0.69 this was handled via a hardcoded memory pressure level: https://github.com/facebook/react-native/blob/c5c17985dae402725abb8a3a94ccedc515428711/React/CxxBridge/RCTCxxBridge.mm#L362 (It seems like the levels are an Android concept - see https://developer.android.com/reference/android/content/ComponentCallbacks2#constants_1) In commit https://github.com/facebook/react-native/commit/0916df99511d6918ea905c2a9df45bccc1fd332a it was changed to run from a constant which could be reconfigured but a mistake (return type of `BOOL` rather than `int`) was resulting in the intended default memory pressure level of 15 (same as the old hardcoded value) being changed to 1 when it was passed on to `handleMemoryPressure`. ## Changelog: [IOS] [FIXED] - UIApplicationDidReceiveMemoryWarningNotification has not been obeyed on iOS since RN 0.69 Pull Request resolved: https://github.com/facebook/react-native/pull/37973 Test Plan: Tested manually via the Simulator using Debug -> Simulate Memory Warning and monitoring the console output of the app. Before fix: ``` WARNING: Logging before InitGoogleLogging() is written to STDERR W0620 11:21:42.824463 257294336 JSIExecutor.cpp:377] Memory warning (pressure level: 1) received by JS VM, unrecognized pressure level ``` With fix (and also the same output for the latest 0.68 tag in the repo): ``` WARNING: Logging before InitGoogleLogging() is written to STDERR I0620 11:25:47.479444 79212544 JSIExecutor.cpp:370] Memory warning (pressure level: TRIM_MEMORY_RUNNING_CRITICAL) received by JS VM, running a GC ``` Reviewed By: javache Differential Revision: D46857205 Pulled By: sammy-SC fbshipit-source-id: 35121e6c4186fded6ef3ba728d9aafbc936627bb
React Native
Learn once, write anywhere:
Build mobile apps with React.
Getting Started · Learn the Basics · Showcase · Contribute · Community · Support
React Native brings React's declarative UI framework to iOS and Android. With React Native, you use native UI controls and have full access to the native platform.
- Declarative. React makes it painless to create interactive UIs. Declarative views make your code more predictable and easier to debug.
- Component-Based. Build encapsulated components that manage their state, then compose them to make complex UIs.
- Developer Velocity. See local changes in seconds. Changes to JavaScript code can be live reloaded without rebuilding the native app.
- Portability. Reuse code across iOS, Android, and other platforms.
React Native is developed and supported by many companies and individual core contributors. Find out more in our ecosystem overview.
Contents
- Requirements
- Building your first React Native app
- Documentation
- Upgrading
- How to Contribute
- Code of Conduct
- License
📋 Requirements
React Native apps may target iOS 12.4 and Android 5.0 (API 21) or newer. You may use Windows, macOS, or Linux as your development operating system, though building and running iOS apps is limited to macOS. Tools like Expo can be used to work 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:
📖 Documentation
The full documentation for React Native can be found on our website.
The React Native documentation discusses components, APIs, and topics that are specific to React Native. For further documentation on the React API that is shared between React Native and React DOM, refer to the React documentation.
The source for the React Native documentation and website is hosted on a separate repo, @facebook/react-native-website.
🚀 Upgrading
Upgrading to new versions of React Native may give you access to more APIs, views, developer tools, and other goodies. See the Upgrading Guide for instructions.
React Native releases are discussed in this discussion repo.
👏 How to Contribute
The main purpose of this repository is to continue evolving React Native core. We want to make contributing to this project as easy and transparent as possible, and we are grateful to the community for contributing bug fixes and improvements. Read below to learn how you can take part in improving React Native.
Code of Conduct
Facebook has adopted a Code of Conduct that we expect project participants to adhere to. Please read the full text so that you can understand what actions will and will not be tolerated.
Contributing Guide
Read our Contributing Guide to learn about our development process, how to propose bugfixes and improvements, and how to build and test your changes to React Native.
Open Source Roadmap
You can learn more about our vision for React Native in the Roadmap.
Good First Issues
We have a list of good first issues that contain bugs which have a relatively limited scope. This is a great place to get started, gain experience, and get familiar with our contribution process.
Discussions
Larger discussions and proposals are discussed in @react-native-community/discussions-and-proposals.
📄 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.