(Smooth)ScrollToPosition doesn't work properly with RecyclerView

Question

I\'m using basic RecyclerView with GridLayoutManager. I observed that nor smoothScrollToPosition nor scrollToPosition works properly.

a) when using smoothScrol

Answer 1

So i was looking for a solution to get back to the top with a recyclerview inside another layout that has a view on top of it (in my case I had a LinearLayout with a TextView and my recyclerview inside). Because of that the smoothscroll would go only to half the way to the first item.

Here's what I did which works really well (Kotlin solution):

back_to_top.setOnClickListener {
        GlobalScope.launch(Dispatchers.Main) {
            GlobalScope.launch(Dispatchers.Main) {
                recyclerview.layoutManager?.smoothScrollToPosition(recyclerview, RecyclerView.State(), 0)
                delay((recyclerview.layoutManager as LinearLayoutManager).findLastVisibleItemPosition() * 100L)
            }.join()
            recyclerview.scrollToPosition(0)
        }
        back_to_top.visibility = View.GONE
    }
}

Here what I do is I smoothscroll to the first element and delay the scroll by 100ms times the last item visible and then call the scrollToPosition(0) (which goes to the top.correctly)