RecyclerView NotifyItemInserted

I have a RecyclerView.Adapter with hasStableIds(true); and a LinearLayoutManager with reverseLayout(true);

RecyclerView.Adapter

hasStableIds(true);

LinearLayoutManager

reverseLayout(true);

I insert a new item to the object list in the adapter then call NotifyItemInserted(0). The list is reversed and loads from bottom to top with the new item always at the bottom.

NotifyItemInserted(0)

new item

The problem is when calling NotifyItemInserted all of the ViewHolders are "Refreshed" / "Reloaded" / "Recreated" - The viewholders are a bit complex and do not want them all to be recreated each time.

NotifyItemInserted

When I debug the solution, OnBindViewHolder starts from position 0 (Which is correct) then goes up to position 10 or 11 depending on how many items there are on screen, recreating them all.

OnBindViewHolder

I have tried many different settings on the adapter, layoutmanager and the recyclerview itself which none of them work.

adapter

layoutmanager

recyclerview

I see there is a payload which can be passed in NotifyItemChanged but not in NotifyItemInserted. Maybe with the payload I can check whether the item is already on screen and don't recreate it again, I don't know what to do.

NotifyItemChanged

NotifyItemInserted

I am using Xamarin.Android but that should not be a problem here.

1 Answer
1

Removing hasStableIds(true) should solve your problem.

hasStableIds(true)

Reason:

When you set hasStableIds to true, the Adapter assumes that every item has a unique id, and it uses the values returned from the getItemId(int position) method to animate data changes for you.

hasStableIds

true

Adapter

getItemId(int position)

That's an easy way to animate changes without any effort (As long as the getItemId(int position) really returns a unique id per item, otherwise you'll crash).

getItemId(int position)

But in your case you want to animate changes by yourself and control which items will be re-rendered and which will not.

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