FabBottomNavogationTransform.kt

fun transform(fab: FloatingActionButton) {
        if (fab.isVisible) {
            fab.hide(object : FloatingActionButton.OnVisibilityChangedListener() {
                override fun onHidden(fab: FloatingActionButton?) {
                    super.onHidden(fab)
                    ValueAnimator.ofFloat(materialShapeDrawable.interpolation, 0F).apply {
                        addUpdateListener { materialShapeDrawable.interpolation = it.animatedValue as Float }
                        start()
                    }
                }
            })
        } else {
            ValueAnimator.ofFloat(materialShapeDrawable.interpolation, 1F).apply {
                addUpdateListener { materialShapeDrawable.interpolation = it.animatedValue as Float }
                doOnEnd { fab.show() }
                start()
            }
        }
    }