Step 1- Defined here  some necessary variable  

   boolean isLoading=false;    -> this variable will use to show progressbar below to recyclerview in your xml file  when you scroll your recyclerview list .

  int mPageSize=10;  -> Number of items you want to fetch from server in a once.

      

Step-2 Set addOnScrollListener to recyclerview

int mTotalItemsCount -> Total item on server side.

recyclerView.addOnScrollListener(new RecyclerView.OnScrollListener() {
            @Override
            public void onScrollStateChanged(RecyclerView recyclerView, int newState) {
                super.onScrollStateChanged(recyclerView, newState);
            }
 
            @Override
            public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
                super.onScrolled(recyclerView, dx, dy);
                // if dy>0 scrolling down side
                // if dy<0 scrolling upper side
                if (dy < 0) {
                    if ((!isLoading && linearLayoutManager.findFirstCompletelyVisibleItemPosition() == 1) && itemsList.size() < mTotalItemsCount) {
                        isLoading = true;
                        
// this method return pageIndex every time when you hit server to get new data.
                        mPageIndex = returnPageIndex(itemsList.size());
                        loadMoreItems(mPageIndex);
                    }
                }
            }
        });

Step-3 Call loadMoreItems method
 

private void loadMoreItems(int mPageIndex) {
        if (AppUtility.isInternetAvailable(this) == false) {
            AppUtility.showAlertDialog(this, getString(R.string.app_name), getString(R.string.connection_error));
            return;
        }
        // Here will go your server side request code
                // after get response from server gone visibility to progressbar
                mLoadMoreProgressbar.setVisibility(View.GONE);
            // add response items to you items list
              itemsList.add(chatMessageBean);
             // notify adapter
             adapter.notifyDataSetChanged();
            // set isLoading to false
             isLoading = false;
    
    }

Step-4 Call returnPageIndex method

private int returnPageIndex(int sizeOfList) {
        int index = sizeOfList / mPageSize;
        return index;
    }