adding dropdown to joomla registration - joomla2.5

Question

I am want to add a dropdown to joomla 2.5 registration.I believe I can use sql form field type but I want that sql to return all schools of a particular city ( which is in registration form) .So question is how a sql query will accept a parameter?

Answer 1

You have to create one field type in the models==>fields.
for ex: create a php file as schools.php, and then include the following code.
==> schools.php(filename)
defined('JPATH_BASE') or die;
class JFormFieldSchools extends JFormField
{
protected $type = 'Schools';
protected function getInput()
{
// Initialize variables.
$html = array();
$attr = '';
// Initialize some field attributes.
$attr .= $this->element['class'] ? ' class="'.(string) $this->element['class'].'"' : '';
$attr .= ((string) $this->element['disabled'] == 'true') ? ' disabled="disabled"' : '';
$attr .= $this->element['size'] ? ' size="'.(int) $this->element['size'].'"' : '';
// Initialize JavaScript field attributes.
$attr .= $this->element['onchange'] ? ' onchange="'.(string) $this->element['onchange'].'"' : '';
// Get some field values from the form.
$contactId = (int) $this->form->getValue('id');
$categoryId = (int) $this->form->getValue('catid');
// Build the query for the ordering list.
$query = 'SELECT ordering AS value, name AS text' .
' FROM #__contact_details' .
' WHERE catid = ' . (int) $categoryId .
' ORDER BY ordering';
// Create a read-only list (no name) with a hidden input to store the value.
if ((string) $this->element['readonly'] == 'true') {
$html[] = JHtml::_('list.ordering', '', $query, trim($attr), $this->value, $contactId ? 0 : 1);
$html[] = '<input type="hidden" name="'.$this->name.'" value="'.$this->value.'"/>';
}
// Create a regular list.
else {
$html[] = JHtml::_('list.ordering', $this->name, $query, trim($attr), $this->value, $contactId ? 0 : 1);
}
return implode($html);
}
}
Then you have to change the mysql query as your needs.
If have to change on the default joomla registration page then have following path(.../com_users/models/forms/registration.xml ).
<field name="xxxxx" type="Schools"
description="COM_USERS_REGISTER_NAME_DESC"
filter="string"
label="COM_USERS_REGISTER_NAME_LABEL"
message="COM_USERS_REGISTER_NAME_MESSAGE"
required="true"
size="30" />