CodeIgniter Ion Auth - set_hooks example

gistfile1.aw

//this would probably be in a library or model
class activity
{
    function add($type)
    {
        $this->db->insert('activity', array(
            'type'     => $type,
            'datetime' => 'now()',
        ));
    }
}

//set the hook
$this->ion_auth->set_hook('post_register', 'add_meta', 'activity', 'add', array('user_added'));

//other stuff...

//after this is called the hook will be executed automatically
$this->ion_auth->register(...

I keep getting the " Using $this when not in object context" error when trying to call the set_hook from my controller.
say i have something like this:

In Controller

$id = 1;
$update = array('email'=>'someone@nowhere.com','api_key'=>'1234test');
// set hook for update meta data
$this->ion_auth->set_hook('post_update_user', 'update_user_meta', 'users_model', 'update_meta', array($id,$update));                    
$this->ion_auth->update($id,$update);

Model

class Users_model extends CI_Model {

protected $meta_cols = array();
protected $tables = array();

function __construct() {
    parent::__construct();
    $this->meta_cols = $this->db->list_fields('meta');
    $this->tables = $this->db->list_tables();
    }

      function update_meta($user_id, array $data)
      {
          $update = array();
          if(is_array($data))
          {
             foreach($this->meta_cols as $cols)
             {
                 if(array_key_exists($cols, $data))
                 {
                     $update[$cols] = $data[$cols];
                 }
             }
          }

          return count($update) > 0 ? $this->db->where($this->tables['meta'].'.user_id',$user_id)->update($this->tables['meta'],$update) : FALSE;

      }

}

The script chokes on the "foreach($this->meta_cols as $cols)" line when called with the set_hook function.

Change your controller to something like this, note the way the class is passed:

$id = 1;
$update = array('email'=>'someone@nowhere.com','api_key'=>'1234test');
// set hook for update meta data
$this->ion_auth->set_hook('post_update_user', 'update_user_meta', $this->users_model, 'update_meta', array($id,$update));                    
$this->ion_auth->update($id,$update);

thanks!

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thanks

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