For Medium article "Animate Everything! (Android Animation Showcase)"

AnimatedLayoutManager.kt

class AnimatedLayoutManager constructor(private val context: Context) : LinearLayoutManager(context) {
    
    // other code 
  
    override fun scrollVerticallyBy(dy: Int, recycler: RecyclerView.Recycler, state: RecyclerView.State): Int {
        if (childCount == 0) return 0
        val legal = super.scrollVerticallyBy(dy, recycler, state)
        calculateDy(dy)
        updateViews()
        return legal
    }
    
    private fun updateViews() {
        for (i in 0 until childCount) {
            val view = getChildAt(i)
            view.let {
                val value = ((paddingTop - it.top) / it.height.toFloat())
                it.alpha = 1f - value
                var scale = 1f - value / 20f
                if (scale > 1) scale = 1f
                it.scaleX = scale
                it.scaleY = scale
            }
        }
    }
}