comment_type_dropdown example

static $has_items;

        if ( ! isset( $has_items ) ) {
            $has_items = $this->has_items();
        }

        echo '<div class="alignleft actions">';

        if ( 'top' === $which ) {
            ob_start();

            $this->comment_type_dropdown( $comment_type );

            /** * Fires just before the Filter submit button for comment types. * * @since 3.5.0 */
            do_action( 'restrict_manage_comments' );

            $output = ob_get_clean();

            if ( ! empty( $output ) && $this->has_items() ) {