walk_nav_menu_tree()

💡 云策文档标注

概述

walk_nav_menu_tree() 函数用于生成导航菜单项的 HTML 列表内容，通过调用 Walker 类（默认为 Walker_Nav_Menu）的 walk() 方法实现。它接受菜单项数组、深度和参数对象作为输入，返回格式化后的 HTML 字符串。

关键要点

核心功能：处理菜单项数组，生成层次化的 HTML 列表输出，常用于 wp_nav_menu() 内部。
参数说明：接受 $items（菜单项数组）、$depth（深度整数）和 $args（包含 wp_nav_menu() 参数的对象），其中 $args 可包含 menu_class、container、walker 等配置项。
返回值：返回菜单项的 HTML 列表内容字符串，可直接输出或进一步处理。
依赖关系：默认使用 Walker_Nav_Menu 类，但可通过 $args->walker 指定自定义 Walker 实例。
相关函数：与 wp_nav_menu()、Walker::walk() 等紧密关联，用于前端菜单渲染和后端管理界面。

代码示例

// 示例：自定义 metabox 添加登录/注销菜单项（来自用户贡献笔记）
add_action( 'admin_head-nav-menus.php', function() {
    add_meta_box( 'plugin-slug-menu-metabox', "Wordpress Login/Logout", 'wpdocs_plugin_slug_render_menu_metabox', 'nav-menus', 'side', 'default', array( /*custom params*/ ) );
} );

function wpdocs_plugin_slug_render_menu_metabox( $object, $args ) {
  global $nav_menu_selected_id;
  $my_items = array(
    (object) array(
        'ID' => 1,
        'object_id' => 1,
        'type_label' => 'Login',
        'title' => 'Login',
        'url' => wp_login_url(),
        'type' => 'custom',
        'object' => 'plugin-slug-slug',
        'db_id' => 0,
        'menu_item_parent' => 0,
        'post_parent' => 0,
        'target' => '',
        'attr_title' => '',
        'description' => '',
        'classes' => array(),
        'xfn' => '',
    ),
    // 类似结构定义 Logout 项...
  );
  $db_fields = false;
  $walker = new Walker_Nav_Menu_Checklist( $db_fields );
  // 输出 HTML 表单部分...
}

注意事项

函数内部自动处理 Walker 实例：如果 $args->walker 为空，则默认使用 Walker_Nav_Menu。
参数 $args 应包含 wp_nav_menu() 支持的完整选项，如 menu_class、container 等，以确保正确渲染。
在自定义开发中，可通过扩展 Walker 类或修改 $args 来调整菜单输出行为，但需遵循 WordPress 核心结构。

📄 原文内容

Retrieves the HTML list content for nav menu items.

Parameters

$itemsarrayrequired

The menu items, sorted by each menu item’s menu order.

$depthintrequired

Depth of the item in reference to parents.

$argsstdClassrequired

An object containing wp_nav_menu() arguments.

More Arguments from wp_nav_menu( … $args )

Array of nav menu arguments.

menu int|string|WP_Term
Desired menu. Accepts a menu ID, slug, name, or object.
menu_class string
CSS class to use for the ul element which forms the menu.
Default 'menu'.
menu_id string
The ID that is applied to the ul element which forms the menu.
Default is the menu slug, incremented.
container string
Whether to wrap the ul, and what to wrap it with.
Default 'div'.
container_class string
Class that is applied to the container.
Default ‘menu-{menu slug}-container’.
container_id string
The ID that is applied to the container.
container_aria_label string
The aria-label attribute that is applied to the container when it’s a nav element.
fallback_cb callable|false
If the menu doesn’t exist, a callback function will fire.
Default is 'wp_page_menu'. Set to false for no fallback.
before string
Text before the link markup.
after string
Text after the link markup.
link_before string
Text before the link text.
link_after string
Text after the link text.
echo bool
Whether to echo the menu or return it. Default true.
depth int
How many levels of the hierarchy are to be included.
0 means all. Default 0.
Default 0.
walker object
Instance of a custom walker class.
theme_location string
Theme location to be used. Must be registered with register_nav_menu() in order to be selectable by the user.
items_wrap string
How the list items should be wrapped. Uses printf() format with numbered placeholders. Default is a ul with an id and class.
item_spacing string
Whether to preserve whitespace within the menu’s HTML.
Accepts 'preserve' or 'discard'. Default 'preserve'.

Return

string The HTML list content for the menu items.

Source

function walk_nav_menu_tree( $items, $depth, $args ) {
	$walker = ( empty( $args->walker ) ) ? new Walker_Nav_Menu() : $args->walker;

	return $walker->walk( $items, $depth, $args );
}

View all references View on Trac View on GitHub

Uses	Description
Walker_Nav_Menu::__construct()`wp-includes/class-walker-nav-menu.php`	Constructor.
Walker::walk()`wp-includes/class-wp-walker.php`	Displays array of elements hierarchically.

Used by	Description
wp_ajax_add_menu_item()`wp-admin/includes/ajax-actions.php`	Handles adding a menu item via AJAX.
_wp_ajax_menu_quick_search()`wp-admin/includes/nav-menu.php`	Prints the appropriate response to a menu quick search.
wp_nav_menu_item_post_type_meta_box()`wp-admin/includes/nav-menu.php`	Displays a meta box for a post type menu item.
wp_nav_menu_item_taxonomy_meta_box()`wp-admin/includes/nav-menu.php`	Displays a meta box for a taxonomy menu item.
wp_get_nav_menu_to_edit()`wp-admin/includes/nav-menu.php`	Returns the menu formatted to edit.
wp_nav_menu()`wp-includes/nav-menu-template.php`	Displays a navigation menu.

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Changelog

Version	Description
3.0.0	Introduced.

User Contributed Notes

Skip to note 2 content

BlackSwanDev

6 years ago

Add a metabox to WordPress nav-menu and add two predefined links (login, logout).

add_action( 'admin_head-nav-menus.php', function() {
    add_meta_box( 'plugin-slug-menu-metabox', "Wordpress Login/Logout", 'wpdocs_plugin_slug_render_menu_metabox', 'nav-menus', 'side', 'default', array( /*custom params*/ ) );
} );

function wpdocs_plugin_slug_render_menu_metabox( $object, $args )
{
  global $nav_menu_selected_id;
  // Create an array of objects that imitate Post objects
  $my_items = array(
    (object) array(
        'ID' => 1,
        'object_id' => 1,
        'type_label' => 'Login',
        'title' => 'Login',
        'url' => wp_login_url(),
        'type' => 'custom',
        'object' => 'plugin-slug-slug',
        'db_id' => 0,
        'menu_item_parent' => 0,
        'post_parent' => 0,
        'target' => '',
        'attr_title' => '',
        'description' => '',
        'classes' => array(),
        'xfn' => '',
    ),
    (object) array(
        'ID' => 1,
        'object_id' => 1,
        'type_label' => 'Logout',
        'title' => 'Logout',
        'url' => wp_logout_url(),
        'type' => 'custom',
        'object' => 'plugin-slug-slug',
        'db_id' => 0,
        'menu_item_parent' => 0,
        'post_parent' => 0,
        'target' => '',
        'attr_title' => '',
        'description' => '',
        'classes' => array(),
        'xfn' => '',
    ),
  );

  $db_fields = false;
  // If your links will be hierarchical, adjust the $db_fields array below
  if ( false ) { 
    $db_fields = array( 'parent' => 'parent', 'id' => 'post_parent' ); 
  }

  $walker = new Walker_Nav_Menu_Checklist( $db_fields );
  $removed_args = array( 'action', 'customlink-tab', 'edit-menu-item', 'menu-item', 'page-tab', '_wpnonce', );
  ?>
  
    
    
       $walker ) ); ?>
    
    
      
        <input type="submit" class="button-secondary submit-add-to-menu right" value="" name="add-plugin-slug-menu-item" id="submit-plugin-slug-div" />







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函数文档

walk_nav_menu_tree()

概述

关键要点

代码示例

注意事项

Parameters

Return

Source

Changelog

User Contributed Notes

函数文档

概述

关键要点

代码示例

注意事项

Parameters

Return

Source

Related

Changelog

User Contributed Notes