Hi Enclave,
it really depends how your data objets are related to the holder page. If they are attached to a holder page (i.e. managed via a DataObjectManager) then you can use that relation for example:
static $has_one = array(
'ComplaintsHolder' => 'ComplaintsHolder'
);
function Link(){
$Holder = $this->ComplaintsHolder();
$Link = $Holder->Link() . 'retrieve_case/' . $this->ID;
return $Link;
}
I think that should work, perhaps it didn't like constructing the link on return, I vaguely remember having that issue before.
If your DO are not attached to holders directly then you need to fetch the Holder using a DataObject::get() or another method.
Thanks for the advice getting mine working, I will give it a try in the office tomorrow.
Aram