ActivityModel::delete PHP Method

    public function delete($where = [], $options = [])
    {
        if (is_numeric($where)) {
            deprecated('ActivityModel->delete(int)', 'ActivityModel->deleteID(int)');
            $result = $this->deleteID($where, $options);
            return $result;
        } elseif (count($where) === 1 && isset($where['ActivityID'])) {
            return parent::delete($where, $options);
        }
        throw new \BadMethodCallException("ActivityModel->delete() is not supported.", 400);
    }

 /**
  * Delete an activity item.
  *
  * @since 2.0.0
  * @access public
  *
  * @param int $ActivityID Unique ID of item to delete.
  * @param string $TransientKey Verify intent.
  */
 public function delete($ActivityID = '', $TransientKey = '')
 {
     $session = Gdn::session();
     if (!$session->validateTransientKey($TransientKey)) {
         throw permissionException();
     }
     if (!is_numeric($ActivityID)) {
         throw Gdn_UserException('Invalid ID');
     }
     if (!$this->ActivityModel->canDelete($this->ActivityModel->getID($ActivityID))) {
         throw permissionException();
     }
     $this->ActivityModel->delete($ActivityID);
     if ($this->_DeliveryType === DELIVERY_TYPE_ALL) {
         $target = Gdn::request()->get('Target');
         if ($target) {
             // Bail with a redirect if we got one.
             redirect($target);
         } else {
             // We got this as a full page somehow, so send them back to /activity.
             $this->RedirectUrl = url('activity');
         }
     }
     $this->render();
 }