I created custom shipping methods using following link
http://www.smashingmagazine.com/2014/01/15/create-custom-shipping-methods-magento/
Now I want enable /disable option(multiselect) at system->configuration->shipping methods->custom carrier
(For example ups carrier->allowed methods multiselect field in system configuration->shipping methods).
In order to get I'm using following code in system.xml
<allowed_methods translate="label">
<label>Allowed Methods</label>
<frontend_type>multiselect</frontend_type>
<source_model>smashingmagazine_mycarrier/source_methods</source_model>
<sort_order>20</sort_order>
<show_in_default>1</show_in_default>
<show_in_website>1</show_in_website>
<show_in_store>0</show_in_store>
<can_be_empty>1</can_be_empty>
</allowed_methods>
and I created Methods.php in proper place.
class SmashingMagazine_MyCarrier_Model_Source_Methods
{
public function toOptionArray()
{
$arr = array();
//how to get created custom shipping methods here?
return $arr;
}
}