Show toolbar elevation using a RecyclerView

recycler_view_toolbar_elevation.kt

recyclerView.addOnScrollListener(object : RecyclerView.OnScrollListener() {
    override fun onScrolled(recyclerView: RecyclerView, dx: Int, dy: Int) {
        super.onScrolled(recyclerView, dx, dy)
        toolbar.setElevationVisibility()
        
        if (recyclerView.canScrollVertically(-1)) {
            ViewCompat.animate(this).translationZ(toolbarElevation).run {
                interpolator = DecelerateInterpolator()
                duration = animationDuration
                start()
            }
        } else {
            ViewCompat.animate(this).translationZ(0f).run {
                interpolator = DecelerateInterpolator()
                duration = animationDuration
                start()
            }
        }
    }
})