Extend name of group in select box when creating a new customer i admin

Question

When creating a new customer in admin, you are presented with a select box to select a customer group. E.g.

• A custom group
• Another custom group

I have extended the table customer_group to include a column for external_id which is imported from another source. I would like to include the value for external_id in this select box. E.g.

• A custom group (82726)
• Another custom group (23234)
• etc.

Does anyone know how this can be accomplished?

Many thanks!

Answer 1

Checking the eav_attribute table for the attribute group_id you can see the source model (The class that returns the options for the dropdown) is customer/customer_attribute_source_group.

The getAllOptions method uses the class Mage_Customer_Model_Resource_Group_Collection to actually get the array, so we'll rewrite that class.

In it's config.xml you'll need the following

[...]
<global>
    [...]
    <models>
        <customer_resource>
            <rewrite>
                <group_collection>[Namespace]_[Module]_Model_Customer_Resource_Group_Collection</group_collection>
            </rewrite>
        </customer_resource>
    </models>
    [...]
<global>
[...]

Now in the Model directory create a file with path Customer/Resource/Group/Collection.php with the following

class [Namespace]_[Module]_Model_Customer_Resource_Group_Collection extends Mage_Customer_Model_Resource_Group_Collection
{
    /**
     * Convert items array to array for select options
     *
     * rewritten from Varien_Data_Collection
     *
     * @param   string $valueField
     * @param   string $labelField
     * @return  array
     */
    public function toOptionArray($valueField='id', $labelField='name', $additional=array())
    {
        $res = array();

        foreach ($this as $item) {
            $res[] = array(
                'value' => $item->getData($valueField),
                'label' => "{$item->getData($labelField)} ({$item->getData('external_id')})",
            );
        }

        return $res;
    }
}

Which should return you a dropdown with the correct labels