How can I retrieve the current menu location (as registered with register_nav_menus) from inside a nav-walker class?

eg:

<?php

class Special_Nav_Walker extends Walker_Nav_Menu {

    // How can I get `special_menu` here, when the walker is applied to the menu (see below)

}

wp_nav_menu(
    [
        'theme_location'    => 'special_menu',
        'walker'            => new Special_Nav_Walker(),
    ]
);

How can I retrieve the current menu location (as registered with register_nav_menus) from inside a nav-walker class?

eg:

<?php

class Special_Nav_Walker extends Walker_Nav_Menu {

    // How can I get `special_menu` here, when the walker is applied to the menu (see below)

}

wp_nav_menu(
    [
        'theme_location'    => 'special_menu',
        'walker'            => new Special_Nav_Walker(),
    ]
);

• plugin-development
• theme-development
• menus
• walker
• development-strategy

• What are you trying to accomplish? That information is passed into the functions of the Walker_Nav_Menu – czerspalace Commented Sep 19, 2019 at 20:47
• I was considering using menu-locations specific conditionals in a feature I was building. Just wasn't sure where to find the info & figured it'd make a good question because I wasn't able to find a quick answer anywhere. – admcfajn Commented Sep 20, 2019 at 16:25

1 Answer 1

There's no constructor, so it's not available as a property of the class, but each method in the class receives the arguments passed to wp_nav_menu() as an object. For example, start_lvl():

/**
 * Starts the list before the elements are added.
 *
 * @since 3.0.0
 *
 * @see Walker::start_lvl()
 *
 * @param string   $output Used to append additional content (passed by reference).
 * @param int      $depth  Depth of menu item. Used for padding.
 * @param stdClass $args   An object of wp_nav_menu() arguments.
 */
public function start_lvl( &$output, $depth = 0, $args = array() ) {
    if ( 'special_menu' === $args->theme_location ) {
        // Do something.
    }
}

Yes, the default value for $args is an array, but nav walkers receives it as an object, for some reason.

The other methods also make the arguments available, but not necessarily as the 3rd argument. You'll need to see which parameters are passed to each method, but you need to do that when extending a class anyway.