A StickyListHeadersListView that notifies us when we should load (or request) more data

RequestMoreListView.java

import android.content.Context;
import android.util.AttributeSet;
import android.widget.AbsListView;

import se.emilsjolander.stickylistheaders.StickyListHeadersListView;

public class RequestMoreListView extends StickyListHeadersListView implements AbsListView.OnScrollListener {

    private OnRequestMoreListener mOnRequestMoreListener;
    private boolean mIsRequesting;
    private AbsListView.OnScrollListener mExternalOnScrollListener;

    public RequestMoreListView(Context context) {
        super(context);
        initComponents();
    }

    public RequestMoreListView(Context context, AttributeSet attrs) {
        super(context, attrs);
        initComponents();
    }

    public RequestMoreListView(Context context, AttributeSet attrs, int defStyle) {
        super(context, attrs, defStyle);
        initComponents();
    }

    /**
     * Register a callback to be invoked when the ListView reaches the last item
     */
    public void setOnRequestMoreListener(OnRequestMoreListener onRequestMoreListener) {
        mOnRequestMoreListener = onRequestMoreListener;
    }

    @Override
    public void onScrollStateChanged(AbsListView view, int scrollState) {
        if (mExternalOnScrollListener != null) {
            mExternalOnScrollListener.onScrollStateChanged(view, scrollState);
        }
    }

    @Override
    public void onScroll(AbsListView view, int firstVisibleItem, int visibleItemCount, int totalItemCount) {
        if (mExternalOnScrollListener != null) {
            mExternalOnScrollListener.onScroll(view, firstVisibleItem, visibleItemCount, totalItemCount);
        }

        // We only proceed when the registered callback is available
        if (mOnRequestMoreListener != null && !mIsRequesting) {
            // We expect that, the ListView overflows with the items
            if (totalItemCount > visibleItemCount &&
                    // And we've reached the last item
                    (firstVisibleItem + visibleItemCount) >= totalItemCount) {
                setRequesting(true);

                // Notify that we should request more data
                mOnRequestMoreListener.onRequestMore();
            }
        }
    }

    /**
     * @return Whether requesting is underway
     */
    public boolean isRequesting() {
        return mIsRequesting;
    }

    /**
     * @param isRequesting If true, we don't expect to be notified by the OnRequestMoreListener callback.
     *                     Otherwise, the ListView should notify us when we should request more data.
     */
    public void setRequesting(boolean isRequesting) {
        mIsRequesting = isRequesting;
    }

    @Override
    public void setOnScrollListener(AbsListView.OnScrollListener onScrollListener) {
        super.setOnScrollListener(this);
        if (this != onScrollListener) {
            mExternalOnScrollListener = onScrollListener;
        }
    }

    private void initComponents() {
        if (isInEditMode()) {
            return;
        }

        // Use an internal OnScrollListener to watch scrolling on the ListView.
        setOnScrollListener(this);
    }

    /**
     * A callback to be invoked when the ListView reaches the last item
     */
    public interface OnRequestMoreListener {

        void onRequestMore();
    }
}