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react-native/ReactAndroid
Valentin Shergin 59021521e7 Fixed dynamic behavior of <Text adjustsFontSizeToFit={true}> on Android (#31538)
Summary:
This PR fixes https://github.com/facebook/react-native/issues/30717, a bug in `<Text adjustsFontSizeToFit={true}>` implementation that prevents it from adjusting text size dynamically on Android.

The way `adjustsFontSizeToFit` was implemented in https://github.com/facebook/react-native/issues/26389 (and the design of ReactTextShadowNode) implies that Yoga will call `onMeasure` on every size change of a `<Text>` component, which is actually not the case (Yoga can cache the results of the measures, call the function multiple times or do not call at all inferring the size from the size constraints). The implementation of `adjustsFontSizeToFit` computes the adjusted string inside the measure function and then eventually passes that to the view layer where it's being rendered.

The proper fix of this issue requires the full redesign of the measure and rendering pipelines and separating them, and that... would be too invasive. And, I believe, this issue is already fixed in Fabric where this part is already designed this way.

Instead, this diff implements a small workaround: if `adjustsFontSizeToFit` is enabled, we manually dirty the Yoga node and mark the shadow node updated to force remeasuring.

## Changelog

[Android] [Fixed] - Fixed dynamic behavior of <Text adjustsFontSizeToFit={true}> on Android

Pull Request resolved: https://github.com/facebook/react-native/pull/31538

Test Plan: https://user-images.githubusercontent.com/22032/118508162-8c79cc80-b6f4-11eb-853f-a1a09f82935f.mov

Reviewed By: mdvacca

Differential Revision: D28631465

Pulled By: yungsters

fbshipit-source-id: 7db1d22e2a5a464c7bf941d1d3df8e3fe8df66a2
2021-08-24 17:58:12 -07:00
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Building React Native for Android

See the docs on the wiki.

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