Layout Animations for the New Architecture #6055
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piaskowyk
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Great work 👏👏👏
For me, this is ready to merge. Let users test it in real-life scenarios, and we can gather feedback accordingly.
bartlomiejbloniarz
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Nice work guys 👏 |
This was referenced Jul 25, 2024
r0h0gg6
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## Summary This PR brings layout animations to the New Architecture. In the Old Architecture layout animations were implemented separately for iOS and Android. The new implementation leverages the `MountingOverrideDelegate` to intercept and animate layout changes right before they are sent to the platform. This way we can have a unified implementation across platforms (it should also work beyond Android and iOS). ## `MountingOverrideDelegate` The override delegate is called every time a new transaction is about to be mounted. It gives us full access to the mutations list and allows us to change them. This mechanism is used by RN, also in Layout Animations. It is important to note that this way we never commit a new `ShadowTree` - we only change the mutations that are sent to the platform. This means that those changes don't influence the layout of other views, which is consistent with the Old Arch implementation. ## Limitations - configuration of entering animations is done using `nativeID` since I was unable to obtain the `tag` of a view before the animation should start - `skipExiting` does not work properly on android (I'm not sure why the `componentWillUnmount` method is called there earlier than on iOS) - `globalOriginX` and `globalOriginY` currently return the values of `originX` and `originY` - this part will probably require a native `convertPoint` function to be used - due to view flattening some exiting animations behave differently. The issue is explained in [this PR](facebook/react-native#44043). ## Test plan Go through the Layout Animations examples in the FabricExample app.
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Summary
This PR brings layout animations to the New Architecture.
In the Old Architecture layout animations were implemented separately for iOS and Android. The new implementation leverages the
MountingOverrideDelegateto intercept and animate layout changes right before they are sent to the platform. This way we can have a unified implementation across platforms (it should also work beyond Android and iOS).MountingOverrideDelegateThe override delegate is called every time a new transaction is about to be mounted. It gives us full access to the mutations list and allows us to change them. This mechanism is used by RN, also in Layout Animations. It is important to note that this way we never commit a new
ShadowTree- we only change the mutations that are sent to the platform. This means that those changes don't influence the layout of other views, which is consistent with the Old Arch implementation.Limitations
nativeIDsince I was unable to obtain thetagof a view before the animation should startskipExitingdoes not work properly on android (I'm not sure why thecomponentWillUnmountmethod is called there earlier than on iOS)globalOriginXandglobalOriginYcurrently return the values oforiginXandoriginY- this part will probably require a nativeconvertPointfunction to be usedTest plan
Go through the Layout Animations examples in the FabricExample app.