I am trying to make a form with the following dropdown fields:

Country
State / Province
City

I have a row in my database with a list of all cities in the world, I would like to populate the City dropdown field with ONLY cities that are in the country and or state/province that the user selects. For example, If the user selects Ontario, Canada they should only see cities that are in Ontario, Canada. The dropdown currently works but its being populated with all cities in the database. I have tried adding a custom PHP query in the item section of the dropdown field (see below), but this did not work. Please help. Thanks in advance.

My database looks similar to this:

fieldid | value

|

33 | ON|Toronto

| ON|Mississauga

| ON|Brampton

//<code>
$items = array();

$db = JFactory::getDbo();

$items[] = "|Please Select[c]";

// Used a wildcard to target only cities that begin with ON
$db->setQuery("SELECT value FROM #__acymailing_fields WHERE fieldid = 33 AND value LIKE "ON%");
$results = $db->loadObjectList();

foreach ($results as $result) {
$value = $result->value;
$items[] = $value;
}

$items = implode("\n", $items);

return $items;
//</code>