android - Update new data only in recyclerview

You can use this method to update only newly added data in adapter,

adapter.notifyItemRangeChanged(int positionStart, int itemCount);

or use

adapter.notifyItemRangeInserted(int positionStart, int itemCount);

here,

positionStart: is a starting position from where you've inserted data (list size for most cases when inserted at end of list)

itemCount: is number of items inserted to list

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notifyItemRangeInserted

Notify any registered observers that the currently reflected itemCount items starting at positionStart have been newly inserted. The items previously located at positionStart and beyond can now be found starting at position positionStart + itemCount.

This is a structural change event. Representations of other existing items in the data set are still considered up to date and will not be rebound, though their positions may be altered.

positionStart: Position of the first item that was inserted

itemCount: Number of items inserted

notifyItemRangeChanged

Notify any registered observers that the itemCount items starting at position positionStart have changed. Equivalent to calling notifyItemRangeChanged(position, itemCount, null);.

This is an item change event, not a structural change event. It indicates that any reflection of the data in the given position range is out of date and should be updated. The items in the given range retain the same identity.

positionStart: Position of the first item that has changed

itemCount: Number of items that have changed

Different is that notifyItemRangeInserted treats old data as up to date

Use notifyItemRangeChanged() method, like if you have 10 items already and when you scroll down 10 new items added to the array then you should do:

notifyItemRangeChanged(10,array.size())  

Which is : notifyItemRangeChanged(int positionStart, int itemCount)

You should use notifyItemRangeChanged because it reset items only between given range. rather than notifyDataSetChanged which reset all the items of RecyclerView.

Yes you can do that by specifying on which position you inserted the new data by calling

RecyclerView.Adapter#notifyItemInserted(int)

you can use DiffUtil to refresh particular item changes. for reference check this https://proandroiddev.com/diffutil-is-a-must-797502bc1149