BaseAdapter that allows for delayed content

DelayedBaseAdapter

package com.lacronicus.delayedloadingadapterdriver.app;


import android.view.View;
import android.view.ViewGroup;
import android.widget.AbsListView;
import android.widget.BaseAdapter;
import android.widget.ListView;

import java.util.HashSet;
import java.util.Set;

/**
 * this is an extension of baseadapter
 * set this as your adapter AND set it as the scroll listener on your listview
 * loadDelayableContent is called immediately following getInitialView while the listview is not being flung
 * if the listview is in a "flinging" state, loadDelayableContent calls are delayed until the listview has come to a rest
 */
public abstract class DelayableBaseAdapter extends BaseAdapter implements ListView.OnScrollListener {
    public static final int SCROLL_STATE_UNSET = -100;
    int currentScrollState = SCROLL_STATE_UNSET;
    Set<View> needContentLoadedSet;

    protected DelayableBaseAdapter() {
        needContentLoadedSet = new HashSet<View>();
    }

    @Override
    public final View getView(int position, View convertView, ViewGroup parent) {
        needContentLoadedSet.remove(convertView);
        View v = getInitialView(position, convertView, parent);
        //decide if loadDelayableContent should be called now or delayed
        if (currentScrollState == SCROLL_STATE_TOUCH_SCROLL || currentScrollState == SCROLL_STATE_UNSET) {
            loadDelayableContent(position, v);
            if (needContentLoadedSet.contains(v)) {
                needContentLoadedSet.remove(v);
            }
        } else {
            needContentLoadedSet.add(v);
        }
        return v;
    }

    /*
    * This is the equivalent of a standard getView
    *
    * */
    public abstract View getInitialView(int position, View convertView, ViewGroup parent);


    /*
    * use this to make changes to your views once your listview is no longer scrolling
    * */
    public abstract void loadDelayableContent(int position, View view);


    @Override
    public void onScrollStateChanged(AbsListView view, int scrollState) {
        //use new scrollState and old scrollState to do our "state machine"
        switch (scrollState) {
            case SCROLL_STATE_FLING:
                break;
            case SCROLL_STATE_TOUCH_SCROLL:
            case SCROLL_STATE_IDLE:
                if (currentScrollState == SCROLL_STATE_FLING) { //don't call load content if no calls to loadUnloadedContent have been delayed
                    loadUnloadedContent(view);
                }
                break;
        }
        //update current state
        currentScrollState = scrollState;
    }

    private void loadUnloadedContent(AbsListView lv) {
        for (View v : needContentLoadedSet) {
            loadDelayableContent(lv.getPositionForView(v), v);
        }
        needContentLoadedSet.clear();
    }

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

    }
}