nishan (o^▽^o)
097d482446
Summary: This change fixes an issue on iOS where gradients that fade to a transparent color-stop appear dark or "muddy." The fix ensures that the color's hue is preserved during the transition, matching the behavior on Android and web. ### The Problem When creating a gradient on iOS (e.g., linear-gradient(red, transparent)), the transparent keyword is treated as transparent black (rgba(0,0,0,0)). The `CAGradientLayer` on iOS then interpolates all color channels linearly, causing the red, green, and blue components of the start color to fade to 0. This transition through black results in an undesirable dark or "muddy" appearance in the middle of the gradient. ## Changelog: [IOS][FIXED] - Gradient interpolation for transparent colors <!-- Help reviewers and the release process by writing your own changelog entry. Pick one each for the category and type tags: [ANDROID|GENERAL|IOS|INTERNAL] [BREAKING|ADDED|CHANGED|DEPRECATED|REMOVED|FIXED|SECURITY] - Message For more details, see: https://reactnative.dev/contributing/changelogs-in-pull-requests Pull Request resolved: https://github.com/facebook/react-native/pull/52249 Test Plan: Checkout `LinearGradient` example in RNTester, checkout the newly added transparent color transition example, it should render same on android and iOS. | Before | After | | --- | --- | | <img src="https://github.com/user-attachments/assets/c0bb54ad-ed0e-4a80-b37f-0458af0f1f77" width="300"> | <img src="https://github.com/user-attachments/assets/02da921a-bd0e-45c1-881c-cf6460d5ed43" width="300"> | | `linear-gradient(to right, red, transparent)` transitions to black on iOS, creating a dark effect. | The gradient correctly fades the red color's alpha channel to zero | Reviewed By: javache Differential Revision: D77312194 Pulled By: NickGerleman fbshipit-source-id: 053df8e44f52cd22a3f28fd01f583f7d03c66af5
RNTester
The RNTester showcases React Native views and modules.
Running this app
Before running the app, make sure you ran:
git clone https://github.com/facebook/react-native.git
cd react-native
yarn install
Running on iOS
If you are testing non-fabric component, search for and modify the fabric_enabled flag in RNTester's Podfile.
fabric_enabled = false
Also, if you previously built RNTester with fabric enabled, you might need to clean up the build files and Pods.
# Clean the generated files and folders to clean install RNTester
cd packages/rn-tester
yarn clean-ios
If you are still having a problem after doing the clean up (which can happen if you have built RNTester with older React Native versions where files were generated inside the react-native folder.), the best way might be to clean-install react-native (e.g. remove node_modules and yarn install). If after cleaning up, you are still having issues, you might also want to try RCT_NEW_ARCH_ENABLED=0 bundle exec pod install to disable the new architecture as it might be conflicting.
Both macOS and Xcode are required.
cd packages/rn-tester- Install Bundler:
gem install bundler. We use bundler to install the right version of CocoaPods locally. - Install Bundler and CocoaPods dependencies:
bundle install && bundle exec pod installoryarn prepare-ios. - Open the generated
RNTesterPods.xcworkspace. This is not checked in, as it is generated by CocoaPods. Do not openRNTesterPods.xcodeprojdirectly.
Note for Apple Silicon users
If you own a Mac laptop with Apple Silicon, you need to run some different commands to install and run cocoapods.
sudo arch -x86_64 gem install ffi: this installs theffipackage to load dynamically-linked libraries.arch -x86_64 pod install: this runpod installwith the right architecture.
Running on Android
You'll need to have all the prerequisites (SDK, NDK) for Building React Native installed.
You can build and run RN-Tester by using this command from the root of the repo:
yarn android
If you wish to use JSC instead you should invoke:
cd packages/rn-tester
yarn install-android-jsc
yarn start
Note
Building for the first time can take a while.
If you're using a physical device, run adb reverse tcp:8081 tcp:8081 to make sure the device can access Metro.
See Running on Device for additional instructions on using a physical device.
Building from source
Building the app on both iOS and Android means building the React Native framework from source. This way you're running the latest native and JS code the way you see it in your clone of the github repo.
This is different from apps created using react-native init which have a dependency on a specific version of React Native JS and native code, declared in a package.json file (and build.gradle for Android apps).