Peter Abbondanzo 833ab6fe1b Fix onPointerLeave computation by comparing button presses (#50402)
Summary:
Pull Request resolved: https://github.com/facebook/react-native/pull/50402

While investigating pointer events, I noticed that all Android views fire `onPointerLeave`/`onPointerEnter` in rapid succession on every button press. This is because Android fires `ACTION_HOVER_EXIT` on every frame before firing `ACTION_DOWN` (in the same frame). The logic in JSPointerDispatcher needed to be updated to account for this.

Unfortunately, `ACTION_HOVER_EXIT` events have no means of distinguishing between whether they were driven by the mouse actually leaving the view's bounds or by a button press. Some OS implementations fire this event on the frame just before leaving the view's boundaries while others fire after, so pure X/Y position isn't helpful enough. The button state property on `ACTION_HOVER_EXIT` also never gets set in some OS.

To work around this issue, this change posts a callback to the very next frame after receiving `ACTION_HOVER_EXIT`. If no `ACTION_DOWN` event was received in the same frame, it calls all the way through the existing logic. But, if an `ACTION_DOWN` event *is* received, we compare the event timestamps and if they match we don't post `onPointerLeave`.

Changelog: [Android][Fixed] - Prevent onPointerLeave from dispatching during button presses

Reviewed By: vincentriemer

Differential Revision: D72078450

fbshipit-source-id: dcc7cfa4086963ed8599147d60d8406c54cd5d69
2025-04-07 17:54:03 -07:00
2025-04-03 16:13:09 -07:00
2025-02-27 03:13:26 -08:00
2025-03-30 11:01:43 -07:00
2025-04-03 08:31:45 -07:00
2023-09-12 09:21:08 -07:00
2025-02-27 03:13:26 -08:00
2025-02-27 03:13:26 -08:00

React Native

Learn once, write anywhere:
Build mobile apps with React.

React Native is released under the MIT license. Current npm package version. PRs welcome! Follow @reactnative

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

React Native apps may target iOS 15.1 and Android 7.0 (API 24) 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 repository, @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.

Languages
C++ 33%
Kotlin 20%
JavaScript 18.6%
Objective-C++ 11.5%
Objective-C 7.1%
Other 9.7%