Endless recyclerview with two methodlogy

SearchFragment.java

//Old endless recyclerview methodology 
recyclerView.addOnScrollListener(new RecyclerView.OnScrollListener() {

            @Override
            public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
                super.onScrolled(recyclerView, dx, dy);
                visibleItemCount = recyclerView.getChildCount();
                totalItemCount = gridLayoutManager.getItemCount();
                firstVisibleItem = gridLayoutManager.findFirstVisibleItemPosition();
                if (loading) {
                    if (totalItemCount > previousTotal) {
                        loading = false;
                        previousTotal = totalItemCount;
                    }
                }
                if (!loading && (totalItemCount - visibleItemCount) <= (firstVisibleItem + visibleThreshold)) {
                    Log.i(TAG, "onScrolled: " + page);
                    inputQuery.put(PAGE,String.valueOf(page));
                    presenter.getProductByFilter(inputQuery);

                    loading = true;
                }
            }
        });

//New endless recyclerview methodology
//1- in adapter
   public interface EndEvent{
        void reach();
    }

    EndEvent event;
    public void setEndEvent(EndEvent event){
        this.event=event;
    }

 @Override
    public void onBindViewHolder(RecyclerView.ViewHolder holder, int position) {
       
        boolean lastPositionReached = position == productResults.size() - 1;
        if (lastPositionReached) {
            event.reach();//reach to end
        
    }