Ahmed Ibrahim
5d08aab526
Summary: Fixes https://github.com/facebook/react-native/issues/27137 This PR fixes an issue on iOS where RCTTextView height is not calculated as it should for some fonts where font `leading` attributed is not equal to zero, which results in wrong baseline alignment behaviour. The fix for this is by setting `usesFontLeading` property of `NSLayoutManager` to `NO`, which results is a layout behavior that is similar to `UILabel` Probably the documentation for `usesFontLeading` describes why UILabel has a different (correct) layout behavior in that case > // By default, a layout manager will use leading as specified by the font. However, this is not appropriate for most UI text, for which a fixed leading is usually specified by UI layout guidelines. These methods allow the use of the font's leading to be turned off. ## Changelog [iOS] [Fixed] - Fix RCTTextView layout issue that happens on some font with `leading` attribute not equal to zero, which causes wrong base-alignment layout Pull Request resolved: https://github.com/facebook/react-native/pull/27195 Test Plan: Below are the test results before and after the change, and comparing that to native UILabel behavior. The test is done with using system font and custom font (`GothamNarrow-Medium`) and font size 50 [GothamNarrow-Medium.otf.zip](https://github.com/facebook/react-native/files/3832143/GothamNarrow-Medium.otf.zip) ```js const App: () => React$Node = () => { return ( <View style={{flex: 1, margin: 40, flexDirection: 'row', justifyContent: 'center', alignItems: 'baseline'}}> <View style={{width: 30, height: 30, backgroundColor: 'lightgray'}} /> <Text style={{fontSize: 50, backgroundColor: 'green', fontFamily: 'GothamNarrow-Medium'}}>{'Settings'}</Text> </View> ); }; ``` ------- ### Before the fix <img width="962" alt="Screenshot 2019-11-11 at 16 53 26" src="https://user-images.githubusercontent.com/5355138/68601049-dd778780-04a3-11ea-879e-cc7b4eb2af95.png"> ----- ### After the fix <img width="944" alt="Screenshot 2019-11-11 at 16 55 11" src="https://user-images.githubusercontent.com/5355138/68601180-1d3e6f00-04a4-11ea-87bc-61c6fa2cdb18.png"> ----- ### Using `UILabel` <img width="805" alt="Screenshot 2019-11-11 at 16 59 28" src="https://user-images.githubusercontent.com/5355138/68601487-b2d9fe80-04a4-11ea-9a0f-c025c7753c24.png"> Differential Revision: D19576556 Pulled By: shergin fbshipit-source-id: 4eaafdab963c3f53c461884c581e205e6426718a
React Native
Learn once, write anywhere:
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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.
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Contents
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📋 Requirements
React Native apps may target iOS 10.0 and Android 4.1 (API 16) 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
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📖 Documentation
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