Question

我确实经历了这个：https://www.elegantthemes.com/blog/tips-tricks/how-to-create-custom-menu-structures-in-wordpress

我按照上面的文章创建了第3级的子菜单。然而，在前端，Woocommerce（青苹果）的第三级产品类别没有出现在下拉列表中。

我还读了一个stackoverflow的答案，它说不可能创建第三级子菜单。我确实相信这是一个解决方法。请告诉我。

谢谢。

根据@Rafin的回答，

如果在所有第二级之后放置第三级，则它会显示但这不是第二级菜单（apple）的子菜单应该是的位置。

后端的

，放在所有第二级菜单之后

在前端以这种方式显示，

但我需要这样安排：

Answer 1

您可以使用以下扩展 Wordpress导航菜单

的Walker类

<?php    
class ods_bootstrap_navwalker extends Walker_Nav_Menu {

    /**
     * @see Walker::start_lvl()
     * @since 3.0.0
     *
     * @param string $output Passed by reference. Used to append additional content.
     * @param int $depth Depth of page. Used for padding.
     */
    public function start_lvl( &$output, $depth = 0, $args = array() ) {
        $indent = str_repeat( "\t", $depth );
        $output .= "\n$indent<div class=\"drop\"><ul role=\"menu\" class=\" dropdown-menu\">\n";
    }

    /**
     * @see Walker::start_el()
     * @since 3.0.0
     *
     * @param string $output Passed by reference. Used to append additional content.
     * @param object $item Menu item data object.
     * @param int $depth Depth of menu item. Used for padding.
     * @param int $current_page Menu item ID.
     * @param object $args
     */
    public function start_el( &$output, $item, $depth = 0, $args = array(), $id = 0 ) {
        $indent = ( $depth ) ? str_repeat( "\t", $depth ) : '';

        /**
         * Dividers, Headers or Disabled
         * =============================
         * Determine whether the item is a Divider, Header, Disabled or regular
         * menu item. To prevent errors we use the strcasecmp() function to so a
         * comparison that is not case sensitive. The strcasecmp() function returns
         * a 0 if the strings are equal.
         */
        if ( strcasecmp( $item->attr_title, 'divider' ) == 0 && $depth === 1 ) {
            $output .= $indent . '<li role="presentation" class="divider">';
        } else if ( strcasecmp( $item->title, 'divider') == 0 && $depth === 1 ) {
            $output .= $indent . '<li role="presentation" class="divider">';
        } else if ( strcasecmp( $item->attr_title, 'dropdown-header') == 0 && $depth === 1 ) {
            $output .= $indent . '<li role="presentation" class="dropdown-header">' . esc_attr( $item->title );
        } else if ( strcasecmp($item->attr_title, 'disabled' ) == 0 ) {
            $output .= $indent . '<li role="presentation" class="disabled"><a href="#">' . esc_attr( $item->title ) . '</a>';
        } else {

            $class_names = $value = '';

            $classes = empty( $item->classes ) ? array() : (array) $item->classes;
            $classes[] = 'scroll menu-item-' . $item->ID;

            $class_names = join( ' ', apply_filters( 'nav_menu_css_class', array_filter( $classes ), $item, $args ) );

            if ( $args->has_children )
                $class_names .= ' dropdown';

            if ( in_array( 'current-menu-item', $classes ) )
                $class_names .= ' active';

            $class_names = $class_names ? ' class="' . esc_attr( $class_names ) . '"' : '';

            $id = apply_filters( 'nav_menu_item_id', 'menu-item-'. $item->ID, $item, $args );
            $id = $id ? ' id="' . esc_attr( $id ) . '"' : '';

            $output .= $indent . '<li' . $id . $value . $class_names .'>';

            $atts = array();
            $atts['title']  = ! empty( $item->title )   ? $item->title  : '';
            $atts['target'] = ! empty( $item->target )  ? $item->target : '';
            $atts['rel']    = ! empty( $item->xfn )     ? $item->xfn    : '';
            $atts['class']    = "back-top";

            // If item has_children add atts to a.
            if ( $args->has_children && $depth === 0 ) {
                $atts['href']           = '#';
                $atts['data-toggle']    = 'dropdown';
                $atts['class']          = 'dropdown-toggle';
                $atts['aria-haspopup']  = 'true';
            } else {
                $atts['href'] = ! empty( $item->url ) ? $item->url : '';
            }

            $atts = apply_filters( 'nav_menu_link_attributes', $atts, $item, $args );

            $attributes = '';
            foreach ( $atts as $attr => $value ) {
                if ( ! empty( $value ) ) {
                    $value = ( 'href' === $attr ) ? esc_url( $value ) : esc_attr( $value );
                    $attributes .= ' ' . $attr . '="' . $value . '"';
                }
            }

            $item_output = $args->before;

            /*
             * Glyphicons
             * ===========
             * Since the the menu item is NOT a Divider or Header we check the see
             * if there is a value in the attr_title property. If the attr_title
             * property is NOT null we apply it as the class name for the glyphicon.
             */
            if ( ! empty( $item->attr_title ) )
                $item_output .= '<a'. $attributes .'><span class="glyphicon ' . esc_attr( $item->attr_title ) . '"></span>&nbsp;';
            else
                $item_output .= '<a'. $attributes .'>';

            $item_output .= $args->link_before . apply_filters( 'the_title', $item->title, $item->ID ) . $args->link_after;
            $item_output .= ( $args->has_children && 0 === $depth ) ? ' <span class="icon-play"></span></a>' : '</a>';
            $item_output .= $args->after;

            $output .= apply_filters( 'walker_nav_menu_start_el', $item_output, $item, $depth, $args );
        }
    }

    /**
     * Traverse elements to create list from elements.
     *
     * Display one element if the element doesn't have any children otherwise,
     * display the element and its children. Will only traverse up to the max
     * depth and no ignore elements under that depth.
     *
     * This method shouldn't be called directly, use the walk() method instead.
     *
     * @see Walker::start_el()
     * @since 2.5.0
     *
     * @param object $element Data object
     * @param array $children_elements List of elements to continue traversing.
     * @param int $max_depth Max depth to traverse.
     * @param int $depth Depth of current element.
     * @param array $args
     * @param string $output Passed by reference. Used to append additional content.
     * @return null Null on failure with no changes to parameters.
     */
    public function display_element( $element, &$children_elements, $max_depth, $depth, $args, &$output ) {
        if ( ! $element )
            return;

        $id_field = $this->db_fields['id'];

        // Display this element.
        if ( is_object( $args[0] ) )
           $args[0]->has_children = ! empty( $children_elements[ $element->$id_field ] );

        parent::display_element( $element, $children_elements, $max_depth, $depth, $args, $output );
    }

    /**
     * Menu Fallback
     * =============
     * If this function is assigned to the ods_nav_menu's fallback_cb variable
     * and a manu has not been assigned to the theme location in the WordPress
     * menu manager the function with display nothing to a non-logged in user,
     * and will add a link to the WordPress menu manager if logged in as an admin.
     *
     * @param array $args passed from the ods_nav_menu function.
     *
     */
    public static function fallback( $args ) {
        if ( current_user_can( 'manage_options' ) ) {

            extract( $args );

            $fb_output = null;

            if ( $container ) {
                $fb_output = '<' . $container;

                if ( $container_id )
                    $fb_output .= ' id="' . $container_id . '"';

                if ( $container_class )
                    $fb_output .= ' class="' . $container_class . '"';

                $fb_output .= '>';
            }

            $fb_output .= '<ul';

            if ( $menu_id )
                $fb_output .= ' id="' . $menu_id . '"';

            if ( $menu_class )
                $fb_output .= ' class="' . $menu_class . '"';

            $fb_output .= '>';
            $fb_output .= '<li><a href="' . admin_url( 'nav-menus.php' ) . '">Add a menu</a></li>';
            $fb_output .= '</ul>';

            if ( $container )
                $fb_output .= '</' . $container . '>';

            echo $fb_output;
        }
    }
}

您可以使用

显示菜单

<?php
                    wp_nav_menu( array(
                    'menu'              => your_menu_name,
                    'theme_location'    => your_menu_location,
                    'depth'             => 3,
                    'container'         => '',
                    'container_class'   => '',
                    'container_id'      => 'bs-example-navbar-collapse-1',
                    'menu_class'        => 'navigation',
                    'fallback_cb'       => 'ods_bootstrap_navwalker::fallback',
                    'walker'            => new ods_bootstrap_navwalker())
                    );
                ?>

参考https://developer.wordpress.org/reference/classes/walker_nav_menu/

Answer 2

简单的代码在这里，您可以随心所欲地自定义 HTML

 $parent = array();
      $menu_name = 'menu-1'; //change menu name 
      if (($locations = get_nav_menu_locations()) && isset($locations[$menu_name]))
      {
        $menu = wp_get_nav_menu_object($locations[$menu_name]);
        $menu_items = wp_get_nav_menu_items($menu->term_id);
       
        $parent_id = 0;

        foreach((array)$menu_items as $key => $menu_item)
        {
         
          if($menu_item->menu_item_parent == 0)
          {
            $parent_id = $menu_item->db_id;
            $title = $menu_item->title;
            $url = $menu_item->url;
            array_push($parent, array("title" => $title, "url" => $url, "child" => array()));
          }
          else if($menu_item->menu_item_parent == $parent_id)
          {
            $childId = $menu_item->ID;
            $title = $menu_item->title;
            $url = $menu_item->url;
            array_push($parent[count($parent) - 1]["child"], array("ID"=>$childId,"title" => $title, "url" => $url));
          }
        
        
        
        }
      }
    
    foreach($parent as $key=>$childval){
        $parent[$key]['child']['subchild'];
        if (!empty($childval['child'])) {
            for($i=0;$i<count($childval['child']);$i++){
    
       foreach($menu_items as $childitems){
           if($childitems->menu_item_parent==$childval['child'][$i]['ID']){
               $values = array("ID"=>$childitems->ID,"title" => $childitems->title, "url" => $childitems->url);
            $parent[$key]['child'][$i]['childvalue'][] = $values;
           }
       }
            }
        }
        
    }
echo "<pre>";
print_r($parent);

？

这将打印您的数组，然后根据您进行修改。稍后再谢谢我.. 演示 HTML 在这里

 <ul class="nav navbar-nav">
            <?php
            
              foreach ($parent as $key => $value)
              {
                if(empty($value["child"]))
                {
                  echo "<li><a href='" . $value["url"] . "'>" . $value["title"] . "</a></li>";
                }
                else
                {
                  echo '<li class="dropdown"><a href="' . $value["url"] . '" class="dropdown-toggle" data-toggle="dropdown">' . $value["title"] . ' <b class="caret"></b></a><ul class="dropdown-menu">';
                  foreach ($value["child"] as $key => $value)
                  {
                    echo '<li><a href="' . $value["url"] . '">' . $value["title"] . '</a></li>';
                    echo "<ul>";
                    foreach ($value['childvalue'] as $childval ){
                    echo '<li><a href="' . $childval["url"] . '">' . $childval["title"] . '</a></li>';
                }
                echo "</ul>";
                  }
                  echo '</ul></li>';
                }
              }
            ?>
</ul>

无法在wordpress中创建超过两个级别的子菜单

2 个答案: