Android : Populating ParseObject in a ListFragment using custom adapter

I am trying to populate a ListFragment, using a custom ArrayAdapter and a custom Data Object. The persistent remote store is a Parse data set which maps to the custom Data object I've created. The problem is that I cannot populate the queried response from Parse in the array list that is fed to the arrayadapter. When I do this with dummy data, it works fine. When I do with the List, it doesn't.

Would appreciate any help on this.

Snippets:

private List<DataItem> itemsList; //Initialize a list of Data Items type

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);

    itemsList = new ArrayList<DataItem>();

    //Parse Initialised here

    ParseQuery<ParseObject> query = ParseQuery.getQuery("object");
    query.findInBackground(new FindCallback<ParseObject>() {
        @Override
        public void done(List<ParseObject> objectList, ParseException e) {
            if(e == null){
                addItem(objectList);
            } else {
                Log.d("List Activity",e.getMessage());
            }
        }
    });

    //Static Data Population - This works fine
    DataItem item1 = new DataItem();
    item.setName("SampleName");
    item.setPhone("12345678");
    item.setAddress("Mumbai");

    //Set Adapter
    ListAdapter adapter = new ListAdapter(getActivity(), itemsList);
    setListAdapter(adapter);
    adapter.notifyDataSetChanged();
}

public void addItem(List<ParseObject> objectList){
    for(int i =0; i< objectList.size(); i++){
        DataItem item = new DataItem();
        item.setName(objectList.get(i).getString("name").toString());
        item.setPhone(objectList.get(i).getString("phone").toString());
        item.setAddress(objectList.get(i).getString("address").toString());
        itemsList.add(item); //This is not working
    }

}