// populate category array from database
// only called on first rendering of the tab, after that the array is filled
if (categoryArray.length == 0) {
    var db = Titanium.Database.open('contentDB');
    var dbrows = db.execute('select category_id, category_name from categories order by category_name asc');
    while (dbrows.isValidRow()) {
        categoryArray.push({
            catid:dbrows.fieldByName('category_id'),
            title:dbrows.fieldByName('category_name')
        });
        Ti.API.info("Found category: "+dbrows.fieldByName('category_name')+" ["+dbrows.fieldByName('category_id')+"]");
        dbrows.next();
    }
    dbrows.close();
    db.close();
}