class Opml

class Opml extends StylePluginBase {
  
  /**
   * {@inheritdoc}
   */
  protected $usesRowPlugin = TRUE;
  
  /**
   * {@inheritdoc}
   */
  public function attachTo(array &$build, $display_id, Url $feed_url, $title) {
    $display = $this->view->displayHandlers
      ->get($display_id);
    $url_options = [];
    $input = $this->view
      ->getExposedInput();
    if ($input) {
      $url_options['query'] = $input;
    }
    $url_options['absolute'] = TRUE;
    $url = $feed_url->setOptions($url_options)
      ->toString();
    if ($display->hasPath()) {
      if (empty($this->preview)) {
        $build['#attached']['feed'][] = [
          $url,
          $title,
        ];
      }
    }
    else {
      $this->view->feedIcons[] = [
        '#theme' => 'feed_icon',
        '#url' => $url,
        '#title' => $title,
      ];
    }
  }
  
  /**
   * {@inheritdoc}
   */
  public function render() {
    $rows = [];
    foreach ($this->view->result as $row_index => $row) {
      $this->view->row_index = $row_index;
      $rows[] = $this->view->rowPlugin
        ->render($row);
    }
    $build = [
      '#theme' => $this->themeFunctions(),
      '#view' => $this->view,
      '#options' => $this->options,
      '#rows' => $rows,
    ];
    unset($this->view->row_index);
    return $build;
  }

}