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Jetpack Compose version: 1.4.0-beta02 Jetpack Compose component used: androidx.compose.material.BottomSheetState Android Studio Build: Android Studio Electric Eel | 2022.1.1 Patch 2 Kotlin version: 1.8.10

As per title, after the removal of the targetValue isn't possible to know if a bottom sheet is expanding or collapsing.

The use case on why this is needed is to change the alpha of an element depending on the current expanded progress of the bottom sheet itself.

The bottomSheetState.progress goes always from 0.0 to 1.0, no matter if is expanding or collapsing.

And checking the current value doesn't help, because it switches from Expanded to Collapsed remaining with the value of 1.0:

Expanded - 0.91185045
Expanded - 0.93893886
Expanded - 0.97347516
Expanded - 0.9933874
Expanded - 1.0
Collapsed - 1.0
Collapsed - 0.342198
Collapsed - 0.39998567
Collapsed - 0.48986524
Collapsed - 0.5680212
Collapsed - 0.6550029
Collapsed - 0.7393994
Collapsed - 0.83361727
Collapsed - 0.9114269
Collapsed - 1.0
Expanded - 1.0

Before it was possible to control the alpha of the element with this logic:

        val fraction = bottomSheetState.progress.fraction
        val targetValue = bottomSheetState.targetValue
        val currentValue = bottomSheetState.currentValue
        return when {
            currentValue == BottomSheetValue.Collapsed && targetValue == BottomSheetValue.Collapsed -> 0f
            currentValue == BottomSheetValue.Expanded && targetValue == BottomSheetValue.Expanded -> 1f
            currentValue == BottomSheetValue.Collapsed && targetValue == BottomSheetValue.Expanded -> fraction
            else -> 1 - fraction
        }

But now, without the target value, it is impossible because, once you fully expand or fully collapse the bottom sheet, the currentValue will change from Expanded to Collapse, but the progress will stay to 1.0.

Steps to Reproduce or Code Sample to Reproduce: 1.Add a bottom BottomSheetScaffold with a bottom sheet 2.Try to change the alpha of a component depending on the current expanded/collapsed state, so that the alpha should decrease when the bottom sheet shrink and increase when it expand.