Not remembering position in all cases

[nikclayton]

Occasional reports (through to 2.8.1) that the reading position is not remembered in all cases.

Current code looks something like this:

    fun saveVisibleId(statusId: String? = null) {
        val id = statusId ?: layoutManager.findFirstCompletelyVisibleItemPosition()
            .takeIf { it != RecyclerView.NO_POSITION }
            ?.let { adapter.snapshot().getOrNull(it)?.id }
        
        id?.let {
            Timber.d("saveVisibleId: Saving ID: %s", it)
            viewModel.accept(InfallibleUiAction.SaveVisibleId(visibleId = it))
        } ?: Timber.d("saveVisibleId: Not saving, as no ID was visible")
    }

The problem is -- what happens if there is no item that is completely visible.

Consider a post that is longer than the screen. It's not completely visible, so id is null and the position is not saved.

Or consider two posts that are individually shorter than the screen, but if the user is scrolled so that they are both visible, neither of them is fully visible. Again, since neither post is fully visible id will be null and the position is not saved.

Solution is probably to fall back to the saving the position of the last visible item if no item is fully visible.