Add menu and submenu in admin with a URL instead of slug?

Question

I use this function and hook:

function mysite_admin_menu() 
{
  add_menu_page( 'Categories', 'Catégories', 'administrator', 'categories', 'a_function' );
  add_submenu_page( 'categories', 'Manage', 'Manage', 'administrator', 'xxx', 'a_function' );
  remove_submenu_page('categories','categories');
}
add_action( 'admin_menu', 'mysite_admin_menu' );

It displays what I need: a menu with a submenu on the left admin menu bar.

The thing is, the submenu leads to this page: admin.php?page=xxx.

How can I do to link to a URL like edit-tags.php?taxonomy=category?

If I swap the slug in the add_submenu_page with a relative URL, the link will lead to admin.php?page=edit-tags.php?taxonomy=category.

Whatever I do, I always get admin.php?page=... which is not what I want.

Answer 1

This is an old post but can't you just use wordpress $menu and/or $submenu globals like Oleg suggested in number 2.

When in doubt copy WordPress:

wordpress/wp-admin/menu.php

For example to add link this seems like it would work:

function add_external_link_admin_submenu() {
    global $submenu;
    $permalink = admin_url( 'edit-tags.php' ).'?taxonomy=category';
    $submenu['options-general.php'][] = array( 'Manage', 'manage_options', $permalink );
}
add_action('admin_menu', 'add_external_link_admin_submenu');

You can replace the $permalink = ... with anything

So this should also work :

$permalink = 'http://www.example.com';

Also, it's suggested not to use 'administrator' (even though I use it as well. Anyway, read this ticket for alternative solutions.

Answer 2

I don't recommend you do that.

Let's assume your prefix for admin.php is _trigger_me_

1. Submenu

   <?php
   
   function _clean_url_to_repalce_admin_menu($url, $original_url, $_context){
       if ($url == 'admin.php?page=_trigger_me_'){
           remove_filter('clean_url', '_clean_url_to_repalce_admin_menu', 10);
           //return admin_url('someotherpage.php);
           return 'http://google.com/';
       }
   }
   if (is_admin())
   add_filter('clean_url', '_clean_url_to_repalce_admin_menu', 10, 3);
   

2. Main Menu

   <?php
   function custom_admin_menu_action_hook(){
       global $menu;
       foreach($menu as $k=>$item){
           if ($item[2] == '_trigger_me_'){
                   $menu[$k][2] = 'http://google.com';
           }
       }
   }
   add_action('admin_menu', 'custom_admin_menu_action_hook', 100);
   

I call both examples as "hacks". They possible to do, but better to not do that.

update.

if case if satisfied with redirection =)

<?php
$hook = add_submenu_page($parent, $title, $menu_title, 'manage_option', 'callback');
add_action("load-{$hook}", create_function('','
    header("Location:", admin_url("someurl.php?blahblahblah"));
    exit;
'));

in case if you want to substitute this by taxonomy page (edit-tags.php)

<?php
add_action('admin_menu', 'admin_menu_edit_tags_page');
function admin_menu_edit_tags_page(){
    // please set $YOURPARENTSLUG as parent slug of your menu item (parent of your menu)
    // manage_tags to manage_terms of your taxonomy capability (its visible whan you var_dump($wp_taxonomies[$taxonomyyouwant]));
    add_submenu_page($YOURPARENTSLUG, 'menu', 'title', 'manage_tags',  'edit-tags.php?taxonomy=taxonomy');
}

Answer 3

If your submenu is missing the admin.php?page= prefix, you should register the parent menu first, then the submenu.

add_action( 'admin_menu', function() {

// Parent menu first
add_menu_page( 'Page title', 'Menu Title', 'capability', 'parent-slug', 'callback' );

// Then the submenus
add_submenu_page( 'parent-slug', 'Submenu Page Title', 'Submenu Title', 'capability', 'slug', 'callback' );

} );

Otherwise the link will be just the slug.

Answer 4

Thank you Oleg, your script works but breaks the admin interface (background colors and images all dissappear for any reason).

But if I have to take this road, I can do this instead:

function changeUrl()
{
    $pageURL = 'http://'.$_SERVER["SERVER_NAME"].$_SERVER["REQUEST_URI"];

    if ($pageURL == 'http://www.mysite.com/wp-admin/admin.php?page=xxxx')
    {
        header ('location:http://www.mysite.com/wp-admin/edit-tags.php?taxonomy=category');
    }
}
add_action( 'admin_menu', 'changeUrl' );

It's seems curious to me that there is no simple way to link a submenu to any url. This kind of redirection is messy...but it works.

Answer 5

Although this is an old problem, I'd like to contribute for consideration this code:

function mysite_admin_menu() 
{
  add_menu_page( 'Categories', 'Catégories', 'administrator', 'categories', 'a_function' );
  add_submenu_page( 'categories', 'Manage', 'Manage', 'administrator', 'manage_categories', 'mysite_manage_categories' );
  remove_submenu_page('categories','categories');
}
add_action( 'admin_menu', 'mysite_admin_menu' );

function mysite_manage_categories() 
{ 

?><script>window.location = "<?php echo admin_url('edit-tags.php?taxonomy=category'); ?>";</script><?php 
    }

it uses javascript redirect instead of creating another add_action to redirect via http.