/**
  * @param SUBSCRIBER $subscriber
  * @param NAMED_OBJECT $obj
  * @param string $page_name
  * @param bool $subscribed
  * @param bool $include_return_url
  * @param string $caption
  */
 protected function show_subscription($subscriber, $obj, $page_name, $subscribed, $include_return_url, $caption)
 {
     if (!$caption) {
         $type_info = $obj->type_info();
         $caption = strtolower($type_info->singular_title);
     }
     $url = new URL($obj->home_page());
     $url->replace_name_and_extension($page_name);
     $url->add_argument('subscribed', !$subscribed);
     $url->add_argument('email', $subscriber->email);
     if ($include_return_url) {
         $url->add_argument('return_url', urlencode($this->env->url(Url_part_no_host)));
     }
     echo '<tr>';
     echo '<th>' . $caption . '</th>';
     echo '<td>' . $obj->title_as_link() . '</td>';
     echo '<td>' . ($subscribed ? 'subscribed' : '<strong>not</strong> subscribed') . '</td>';
     echo '<td><a class="button" href="' . $url->as_html() . '">' . ($subscribed ? 'Unsubscribe' : 'Subscribe') . '</a></td>';
     echo '</tr>';
 }