Most of the AclBehavior works transparently on your Model's afterSave(). However, using it requires that your Model has a parentNode() method defined. This is used by the AclBehavior to determine parent->child relationships. A model's parentNode() method must return null or return a parent Model reference.

function parentNode() { 	return null; } 

1. function parentNode() {
2. return null;
3. }

If you want to set an ACO or ARO node as the parent for your Model, parentNode() must return the alias of the ACO or ARO node.

 function parentNode() {         return 'root_node'; } 

1. function parentNode() {
2. return 'root_node';
3. }

A more complete example. Using an example User Model, where User belongsTo Group.

function parentNode() { 	if (!$this->id && empty($this->data)) { 		return null; 	} 	$data = $this->data; 	if (empty($this->data)) { 		$data = $this->read(); 	}  	if (!$data['User']['group_id']) { 		return null; 	} else { 		$this->Group->id = $data['User']['group_id']; 		$groupNode = $this->Group->node(); 		return array('Group' => array('id' => $groupNode[0]['Aro']['foreign_key'])); 	} }  

1. function parentNode() {
2. if (!$this->id && empty($this->data)) {
3. return null;
4. }
5. $data = $this->data;
6. if (empty($this->data)) {
7. $data = $this->read();
8. }
9. if (!$data['User']['group_id']) {
10. return null;
11. } else {
12. $this->Group->id = $data['User']['group_id'];
13. $groupNode = $this->Group->node();
14. return array('Group' => array('id' => $groupNode[0]['Aro']['foreign_key']));
15. }
16. }

In the above example the return is an array that looks similar to the results of a model find. It is important to have the id value set or the parentNode relation will fail. The AclBehavior uses this data to construct its tree structure.