Wordpress - Add a Separator to the Admin Menu?

Here's a quick and dirty way to get what you want.

Background

WordPress stores admin menu sections in a global array called $menu. To add a separator you add an element to the $menu array using an index that is between the indexes of the options that you want to separate.

Using the add_admin_menu_separator() function

So I've written a function to encapsulate the logic for this I called add_admin_menu_separator(). You'll need to pick an array index number that is higher than the option after which you want to add a separator, and then call the function add_admin_menu_separator() passing said index as your parameter.

For example:

add_admin_menu_separator(37);

The add_admin_menu_separator() function itself

Here's the definition of the function add_admin_menu_separator() which you can copy into your theme's functions.php file. Yes it is arcane but then so is the code that creates and uses the global $menu array. (Plans are to eventually deprecate it, thankfully, but that'll probably be a few years.)

function add_admin_menu_separator($position) {
  global $menu;
  $index = 0;
  foreach($menu as $offset => $section) {
    if (substr($section[2],0,9)=='separator')
      $index++;
    if ($offset>=$position) {
      $menu[$position] = array('','read',"separator{$index}",'','wp-menu-separator');
      break;
    }
  }
  ksort( $menu );
}

Finding the index into $menu that you need

To figure out what index number you need you can do a var_dump() of $GLOBALS['menu'] from within an admin_init hook. Here's a bit of code you can drop into your theme's functions.php file temporarily to see what the values are. This will only work when requesting a URL starting with /wp-admin/ (but be sure to do with with FTP and not the built in theme editor or you'll loose access to your site, at least until you get FTP access to your theme's functions.php file!):

add_action('admin_init','dump_admin_menu');
function dump_admin_menu() {
  if (is_admin()) {
    header('Content-Type:text/plain');
    var_dump($GLOBALS['menu']);
    exit;
  }
}

See Also:

BTW, you might find these links useful in general for working with admin menus:

• Changing the Order of Admin Menu Sections
• Latest: wp-admin-menu-classes.php

Although my admin menu classes don't currently offer an easy way to add separators I think I'll now add that when I have time.

It's easy as:

add_action( 'admin_init', 'add_sep' );
function add_sep() {

    if ( ! is_admin() )
        return false;

    global $menu;
    $sep = $menu[4]; // that's the default separator
    $pos = 6; // change it for the desired position
    $menu = array_merge(
        array_slice( $menu, 0, $pos ),
        array( $sep ),
        array_slice( $menu, $pos + 1, -1)
    );
    $menu[ $pos - 1 ][4] .= ' menu-top-last';
    $menu[ $pos + 1 ][4] .= ' menu-top-first';

}

Note: The default separator position ($menu[4]) can be different depending of which configuration you (or your plugins) have done before this hook.

Of course, you can also tweak the menu-top-first and menu-top-last classes introspection.

Had some issues with separators not being added, it was due to the way wordpress removes duplicate separators. Adding ksort($menu); to the bottom of the function corrected the issue.