Ormlite setup without using base activities

I'm using ORMLite in an android project, and I'm not wanting to use the extended activities because I'm inserting values into the database on an AsyncTask.

In the docs it says:

"If you do not want to extend the OrmLiteBaseActivity and other base classes then you will need to duplicate their functionality. You will need to call OpenHelperManager.getHelper(Context context, Class openHelperClass) at the start of your code, save the helper and use it as much as you want, and then call OpenHelperManager.release() when you are done with it."

It also says to add the database helper class in the strings.xml, which I have. So I'm not sure what I'm doing wrong.

I'm using a class called DataAccess for my data tier that looks like this:

public class DataAccess {
    private Context context;
    private DBHelper dbHelper;

    public DataAccess(Context _context) {
        this.context = _context;
        dbHelper = getDBHelper(_context);
    }

    private DBHelper getDBHelper(Context context) {
        if (dbHelper == null) {
            dbHelper = (DBHelper) OpenHelperManager.getHelper(context, DBHelper.class);
        }
        return dbHelper;
    }
}

And I'm using the extended helper class:

public class DBHelper extends OrmLiteSqliteOpenHelper {
    private static final String DATABASE_NAME = "database.db";
    private static final int DATABASE_VERSION = 1;

    private Dao<SomeObject, Integer> someObjectTable = null;
    private ConnectionSource connectionSource = null;

    public DBHelper(Context context) {
        super(context, DATABASE_NAME, null, DATABASE_VERSION);
    }

    @Override
    public void onCreate(SQLiteDatabase db, ConnectionSource connectionSource) {
        this.connectionSource = connectionSource;
        try {
            TableUtils.createTable(connectionSource,