WordPress：无需hack方法将自定义分类法添加到自定义后台菜单

Great question! I’ve run into this exact issue before, so I know how frustrating it can be when WordPress’s default taxonomy settings feel restrictive. The good news is there are totally legitimate, core-compliant ways to get your custom taxonomy under a custom admin menu—no sketchy hacks or core code changes required. Let’s break down the two most reliable methods:

Method 1: Use the show_in_menu Parameter with Your Custom Menu Slug (Simplest Approach) #

First, let’s clear up a common misconception: the show_in_menu argument for register_taxonomy() doesn’t only accept boolean values. In WordPress 4.4 and later, you can pass a string that matches the slug of your custom parent menu, and the taxonomy will automatically appear as a submenu item.

Here’s a step-by-step example:

1. Register your custom admin menu with add_menu_page(), and make note of the menu slug (the fourth parameter):

   add_action('admin_menu', 'register_my_custom_parent_menu');
   function register_my_custom_parent_menu() {
       add_menu_page(
           'My Custom Dashboard', // Page title (shows in browser tab)
           'Custom Menu',         // Menu title (shows in admin sidebar)
           'manage_options',      // User capability required to access
           'my-custom-menu-slug', // Unique menu slug (this is critical)
           'my_custom_menu_callback', // Callback for the menu page content
           'dashicons-admin-tools', // Menu icon (use a Dashicon)
           20 // Position in the admin sidebar
       );
   }
   

2. When registering your custom taxonomy, set show_in_menu to the slug of your custom parent menu:

   add_action('init', 'register_my_custom_taxonomy');
   function register_my_custom_taxonomy() {
       $taxonomy_args = array(
           'label' => 'Product Categories',
           'public' => true,
           'hierarchical' => true,
           'show_in_menu' => 'my-custom-menu-slug', // Match your custom menu slug here
           // Add other taxonomy settings as needed
       );
       register_taxonomy('product_category', 'custom_product', $taxonomy_args);
   }
   

That’s it! Your taxonomy’s management page will now nest directly under your custom admin menu, no extra work required.

Method 2: Manually Add the Taxonomy as a Submenu Item (Full Control) #

If you need more control over the submenu order, or if you’re working with an older WordPress version where Method 1 isn’t supported, you can manually link the taxonomy’s admin page to your custom menu using add_submenu_page().

Here’s how to do it:

1. First, set show_in_menu to false when registering your taxonomy to hide it from the default admin menu:

   add_action('init', 'register_my_custom_taxonomy');
   function register_my_custom_taxonomy() {
       $taxonomy_args = array(
           'label' => 'Product Tags',
           'public' => true,
           'show_in_menu' => false, // Hide from default menu location
           // Other taxonomy settings...
       );
       register_taxonomy('product_tag', 'custom_product', $taxonomy_args);
   }
   

2. Use add_submenu_page() to add the taxonomy’s existing admin page as a submenu item under your custom menu:

   add_action('admin_menu', 'add_taxonomy_to_custom_menu');
   function add_taxonomy_to_custom_menu() {
       // Construct the URL to the taxonomy's management page
       $taxonomy_admin_url = admin_url('edit-tags.php?taxonomy=product_tag&post_type=custom_product');
       
       // Add it as a submenu to your custom parent menu
       add_submenu_page(
           'my-custom-menu-slug', // Parent menu slug
           'Manage Product Tags', // Page title
           'Product Tags',        // Submenu title
           'manage_options',      // Required capability
           $taxonomy_admin_url    // Use the taxonomy URL as the menu slug (links directly to the page)
       );
   }
   

This method lets you place the taxonomy submenu exactly where you want it, and it’s fully compliant with WordPress best practices—no "hack" required.

Why Your Initial "Hack" Might Be Unnecessary #

The approach of creating a custom submenu page that redirects to the taxonomy page is often labeled a hack, but the two methods above are official, supported ways to achieve the same result cleanly. The key was realizing that show_in_menu accepts a menu slug string (not just true/false) in modern WordPress versions.

内容的提问来源于stack exchange，提问作者Orlando P.