在 recyclerview 中滚动到顶部加载更多数据

Question

I trying to load more data on scroll to top recyclerview Like Whatsapp chat .
my adapter is contain multiple views
I loading few rows from sqlite to display in recyclerview and load more data when scroll the top. when i load the more data the app is crashed

02-20 22:57:01.324 6833-6833/ E/AndroidRuntime: FATAL EXCEPTION: main
Process: , PID: 6833
java.lang.NullPointerException
    at .adapters.PrivateChatAdapter$ViewHodler.setSenderMsg(PrivateChatAdapter.java:208)
    at .adapters.PrivateChatAdapter.onBindViewHolder(PrivateChatAdapter.java:124)
    at .adapters.PrivateChatAdapter.onBindViewHolder(PrivateChatAdapter.java:46)

the linearlayoutmanger is linearLayoutManager.setStackFromEnd(true);

0     <---- i want to load the new data here
1
2    
3
4    
5
6

When i add the new data to arraylist

arrayMsgs.add(0, new PrivateMsg.Builder(PrivateMsg.LOADING_MORE_MSG, 0, true).build());
privateChatAdapter.notifyItemInserted(0);

The old item in position 0 is repeated

Answer 1

I've solved the issue by resetting the adapter as below :

recyclerview.setAdapter(privateChatAdapter);

after adding data to position zero in arraylist
Maybe because the views item stored in cache of the recyclerview