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Xin Chen
bc9168d4ca
Summary: This diff adds `overflowInset` values in RN Android. These values are used to give an enlarged boundary of a view group that also contains all its children layout. Here is [the post](https://fb.workplace.com/groups/yogalayout/permalink/2264980363573947/) that discuss more on why this is useful. I steal the pic in that post here as TLDR: {F687030994} In the above case, we will get overflowInset for ViewGroup A as something like `top: 0, right: -20, bottom: -20, left: 0`. This has been added in the [Fabric core](https://fburl.com/code/f8c5tg7b) and [in IOS](https://fburl.com/code/vkh0hpt6). In Android, since we used to ignore all event coordinates outside of a ViewGroup boundary, this is not an issue. However, that caused unregistered touch area problem and got fixed in D30104853 (https://github.com/facebook/react-native/commit/e35a963bfb93bbbdd92f4dd74d14e2ad6df5e14a), which dropped the boundary check and made the hit test algorithm in [TouchTargetHelper.java](https://fburl.com/code/dj8jiz22) worse as we now need to explore all the child node under ReactRootNode. This perf issue is getting obvious when a view loads too many items, which matches our experience with "Hover getting slow after scrolling", "Hover getting slow after going back from PDP view", and "The saved list view (in Explore) is very fast (because it has very few components)" To fix this issue, I added the support to `overflowInset` to RN Android by 1. Sending the `overflowInset` values from Binding.cpp in RN Android as a separate mount instruction 2. Update `IntBufferBatchMountItem.java` to read the int buffer sent over JNI, and pass the `overflowInset` values to `SurfaceMountingManager.java` 3. Creating new interface `ReactOverflowViewWithInset.java` and extending the existing `ReactOverflowView.java` usages 4. Adding implementation of getter and setter for `overflowInset` in various views 5. Update `TouchTargetHelper.java` to read the values and check boundaries before exploring ViewGroup's children Note that in #3 I didn't change `ReactOverflowView.java` interface directly. I am concerned about backward compatibility issues in case this interface is being used in OSS. I suggest we deprecate it as we are not using it anymore in our code. Changelog: [Internal][Android] Reviewed By: JoshuaGross Differential Revision: D33133977 fbshipit-source-id: 64e3e837fe7ca6e6dbdbc836ab0615182e10f28c
Building React Native for Android
See the docs on the wiki.
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