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Allow a variant of `update` that is akin to clear+addAll, but using notifyDataSetChanged()

See original GitHub issue

Is your feature request related to a problem? Please describe A clear and concise description of what the problem is.

To replace a list of items with a new list of items without using update (DiffUtil), I’m trying to use clear() then addAll(), however, this kills the scroll position on update.

Describe the solution you’d like A clear and concise description of what you want to happen.

Kinda like the (unfortunately private) setNewGroups method of GroupAdapter, I’d love to do:

adapter.replaceItems(Collection<? extends Group>)

But using adapter.notifyDataSetChanged so that scroll position is preserved.

Additional context Add any other context about the problem here.

Currently I’m using a workaround

fun GroupieItemAdapter.replaceItemsWith(
    recyclerView: RecyclerView,
    withAnimations: Boolean = false,
    block: MutableList<GroupieItem>.() -> Unit
): GroupieItemAdapter {
    if (withAnimations) {
        this.update(mutableListOf<GroupieItem>().apply(block))
    } else {
        val layoutManager = recyclerView.layoutManager

        val state = layoutManager?.onSaveInstanceState()

        this.clear()
        this.addAll(mutableListOf<GroupieItem>().apply(block))

        layoutManager?.onRestoreInstanceState(state) // fixme
    }
    return this
}

But I’m not really a fan of it, as there’s a good chance this is unpredictable with non-LinearLayoutManagers.