RecyclerView notifyDataSetChanged 滚动到顶部 position

Question

when calling notifyDataSetChanged on RecyclerView it doesn't retain the scroll position and scrolls to top, is there any solution to retain it's scroll position?

Answer 1

If your RecyclerView list item parent has "wrap_content" property, Recyclerview calculates the heights again and scrolls top.

There are two solutions:

1. Set your height a constant value like this: layout_height="100dp"

2. Use StaggeredGridLayoutManager like this:

   mRecyclerView.setLayoutManager(new StaggeredGridLayoutManager(1, StaggeredGridLayoutManager.VERTICAL));

The second solution is more efficient and I suggest this one

Answer 2

Not sure if this solves your problem but I was having the same issue and it was because I was calling setAdapter after notify. So, not calling setAdapter after notify solved the problem.

mAdapter.notifyItemRangeInserted(mAdapter.getItemCount(), list.size() - 1);
recyclerView.setAdapter(); // remove this line. 
//Do this only when you're setting the data for the first time or when adapter is null. 

Answer 3

As I am guessing, what you are doing is resetting the adapter to the RecyclerView and then calling notifyDataSetChanged().

You need to pass only the dataList to the adapter by passing dataList in adapter method like adapter update(dataList) . And in this method you can assign this list to adapter list like;

public void update(ArrayList<Hashmap<String,String> list){
  this.mList = list;
}

Answer 4

You can use swapAdapter() and after call notifyDataSetChange() . This works for me.

Answer 5

RecycleViews will scroll back to the top on any variant of notifyDataSetChanged if they don't have a layout manager. Here's an example of how to set one.

LinearLayoutManager linearLayoutManager = new LinearLayoutManager(context, OrientationHelper.VERTICAL, false);
recycleView.setLayoutManager(linearLayoutManager);

Answer 6

In my case, the recyclerview was paginated. Every time it reaches the end and loads/inserts item using notifyItemInserted, the recyclerView used to scroll. So following worked for me:

recycler_view.stopScroll();

As stated in the doc:

Stop any current scroll in progress, such as one started by smoothScrollBy(int, int), fling(int, int) or a touch-initiated fling.

Answer 7

notifyItemChanged() make the RecyclerView scroll and jump to UP

android:descendantFocusability="blocksDescendants"

Horizontal recyclerView inside vertical recyclerView generally causes that problem and this is best approach to get rid of problem. Don't put this attr into horizontal recyclerViews, it needs to be in only Parent (vertical RecyclerView).

Answer 8

Use android:descendantFocusability="blocksDescendants" in the parent recyclerView . It will fix the issue. I had a child recyclerView inside the parent recyclerView and this trick helped me. Also except first time you should always use notifyDataSetChanged on the adapter.

Answer 9

This worked for me:

Set the fixed size property on the RecyclerView to "true" which prevents scroll up after calling notifyDataSetChanged on the adapter:

mRecyclerView.setHasFixedSize(true)

Answer 10

You can't scroll to position without having set the adapter first. Set your adapter first, even if your list is empty. Update your list when you get the data. Then call adapter.notifydatasetchanged() method. You can then scroll to the last position. Let me know if this answers your question or if I have to put an answer – mmmcho