fix(android): opacity not animating when combined with rotation#40
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janicduplessis merged 1 commit intomainfrom Apr 14, 2026
Merged
fix(android): opacity not animating when combined with rotation#40janicduplessis merged 1 commit intomainfrom
janicduplessis merged 1 commit intomainfrom
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setBackfaceVisibilityDependantOpacity() resets alpha to 1.0 every frame during rotation animations, overriding animated opacity. Skip the backface check when MASK_OPACITY is set — the opacity animator handles alpha directly in that case.
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Summary
On Android, animating
opacityandrotate(orrotateX/rotateY) simultaneously causes opacity to not animate — the view stays fully opaque.Root cause: React Native's
ReactViewGroup.setBackfaceVisibilityDependantOpacity()resetsalpha = backfaceOpacity(1.0) every frame. EaseView calls this during rotation animations to handle backface visibility, but it overrides the animated opacity value.Fix: Skip the backface alpha reset when
MASK_OPACITYis in the animated bitmask. In that case, the opacity animator manages alpha directly. Applied to all three call sites: first-mount setup, timing animator, and spring animator.Test Plan
yarn lint && yarn test— all 82 tests passopacityandrotatesimultaneously — opacity should now animate correctly