Adds the total amount scrolled to a OnScrollListener for a ListView.

OnTotalScrolledListener.java

public abstract class OnTotalScrolledListener implements AbsListView.OnScrollListener {

    private List<Integer> mHeights = new ArrayList<>();

    @Override
    public void onScroll(AbsListView view, int firstVisibleItem, int visibleItemCount, int totalItemCount) {

        View c = view.getChildAt(0);
        if (c != null) {

            if (mHeights.size() < firstVisibleItem + 1) {
                mHeights.add(c.getHeight());
            } else {
                mHeights.set(firstVisibleItem, c.getHeight());
            }

            int heightSum = 0;
            for (int i = 0; i < firstVisibleItem; i++) {
                heightSum += mHeights.get(i);
            }
            float totalScrolled = -c.getTop() + heightSum;
            onScroll(view, firstVisibleItem, visibleItemCount, totalItemCount, totalScrolled);
        }
        else {
            onScroll(view, firstVisibleItem, visibleItemCount, totalItemCount, 0);
        }
    }

    public abstract void onScroll(AbsListView view, int firstVisibleItem, int visibleItemCount, int totalItemCount, float totalScrolled);
}