Hi ! when the system Reduce Motion accessibility s...

# compose-ios

[Axel Proust]

Hi !
when the system Reduce Motion accessibility setting is enabled, every duration-based animation snaps instantly instead of animating:
- Navigation 3 screen transitions (NavDisplay) hard cut instead of a slide.
- ModalBottomSheet show/hide (both Material3 and composables.core) the sheet just appears instead of arriving.
The cause seems to be androidx.compose.ui.platform.MotionDurationScaleImpl.scaleFactor returning 0 (it reads UIAccessibilityIsReduceMotionEnabled()), which zeroes the duration of all animations.
The result feels broken compared to native iOS, where Reduce Motion doesn’t hard-cut…

Is this a known issue, and is there a recommended way to handle it on iOS? Thanks! 🙏

[Axel Proust]

Gentle bump 🙏
For the context on why this matters for me: we’re an app studio already shipping a CMP app in production, and we’re now deciding whether to standardize our whole stack on it. This is a blocker for that decision (our CEO uses Reduce Motion daily, so “every animation hard-cuts” is his first impression).
Also it’s not just us. The KotlinConf app (also CMP) does the same hard-cut, while RN / Flutter feel softer like native iOS instead of cutting.
Sorry to insist, this bug really landed on the worst possible person on our side 😅

[Chrimaeon]

Did you create a ticket in the issue tracker?

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[Axel Proust]

Thanks for the heads-up, and sorry for posting it here! Not yet. I’ll file it in the issue tracker today :)

[Andrei Salavei]

It's expected that the "Reduce Motion" setting will... well reduce animations.
I would be very appreciate if you could file a ticket that compares behavioral for identical/close components between the iOS and Compose Multiplatform.

[Axel Proust]

To be precise: it’s not that it reduces the animations, it fully snaps them, the transition jumps straight to the end state, zero interpolation. I’ll record a side by side video of the same component 👍
And add it to the ticket :
https://youtrack.jetbrains.com/issue/CMP-10284/iOS-Reduce-Motion-hard-cuts-animations-NavDisplay-transitions-ModalBottomSheet-instead-of-reducing-them