Pagination Not Work for the Recyclerview Within Nestedscrollview

Pagination not work for the RecyclerView within NestedScrollView

Follow this steps :

1. Set nested scrolling enabled false of recycler view.

recyclerView.setNestedScrollingEnabled(false);

2. Add scroll listner to nested scrollview.

 mScrollView.getViewTreeObserver().addOnScrollChangedListener(new ViewTreeObserver.OnScrollChangedListener() {
           @Override
           public void onScrollChanged()
           {
                    View view = (View)mScrollView.getChildAt(mScrollView.getChildCount() - 1);

                    int diff = (view.getBottom() - (mScrollView.getHeight() + mScrollView
                                    .getScrollY()));

                    if (diff == 0) {
                       // your pagination code
                    }
           }
  });

Pagination with RecyclerView within NestedScrollView

to solve this challenge I perform the following Steps:

1- for XML file or EndlessRecyclerViewScrollListener NO CHANGES

2- for my activity I delete EndlessRecyclerViewScrollListener for vertical Recycler and defined my NestedScrollListener instance then set OnScrollChangeListener as below:

    boolean loading = true;
    int pageNumber = 1;
    NestedScrollView scroller = findViewById(R.id.nestedScroll);

    if (scroller != null) {

        scroller.setOnScrollChangeListener((NestedScrollView.OnScrollChangeListener) (v, scrollX, scrollY, oldScrollX, oldScrollY) -> {

            if (scrollY > oldScrollY) {
                Log.i(TAG, "Scroll DOWN");
            }
            if (scrollY < oldScrollY) {
                Log.i(TAG, "Scroll UP");
            }

            if (scrollY == 0) {
                Log.i(TAG, "TOP SCROLL");
            }

            if (scrollY == ( v.getChildAt(0).getMeasuredHeight() - v.getMeasuredHeight() )) {
                Log.i(TAG, "BOTTOM SCROLL");
              // here where the trick is going
                if (loading){
                    pageNumber++;
                    showProgressView(mixedProgressBar);
                    // calling from adapter addToExistingList(list)
                    // with the defined Adapter instance
                    verticalAdapter.addToExistingList(getPosts(pageNumber));
                    // reset the boolean(loading) to prevent
                    // auto loading data from APi
                    loading = false;
                }
            }
        });
    }

3- for VerticalAdapter, I add the following method :

public void addToExistingList(List<DataModel> dataModelList){
    // update oldDataModelList with newer data from pagination
    oldDataModelList.retainAll(dataModelList);
    notifyItemRangeChanged(oldDataModelList.size()-1 , dataModelList.size());
}

4- for getPosts(pageNumber) on fetching data success re-assign the boolean(loading)

getPosts(pageNumber) is a method to invoke data from API

JsonArrayRequest arrayRequest = new JsonArrayRequest(Request.Method.GET,baseAPI,
         response1 -> {
                try {
                       // doing stuff to invoke your data
                        // re-assign loading variable to load again
                        loading = true;

                    } catch (JSONException e) {
                        e.printStackTrace();
                    }

Related Topics