In reference to the WordPress Codex, the Walker class was implemented in WordPress 2.1 to provide developers with a means to traverse tree-like data structures for the purpose of rendering HTML. The detail information about the walker class can be found in the WordPress Codex. Here is a simple example.
$defaults = array(
'theme_location' => 'primary',
'container' => 'ul',
'menu_class' => 'nav navbar-nav main-nav',
'walker' => new Primary_Walker_Nav_Menu()
wp_nav_menu( $defaults );
In the above block of code, the wp_nav_menu() function takes $defaults as […]