private void PopulateGoalsListBox()
        {
            // get categories from DB
            var rdr = DB_API.SelectAccountGoals(account_id);

            // extract goal names for listBox
            this.user_goals = new List <string>();
            var res = new List <string>();

            while (rdr.Read())
            {
                string goal_name = rdr[DB_API.CategoryEnt.name.ToString()].ToString();
                user_goals.Add(goal_name);
                res.Add(goal_name);
            }
            Goals_listBox.DataSource = new List <string>(res);
        }