How to check menu item class in Walker_Nav_Menu - php

Question

I have a custom two level menu in WordPress. There is an upper level and when you hover over the items, a submenu appears. Two menu items in the submenu have a button that is not in the other submenus. These two paragraphs have a "browse all" class. I need to check this class in Walker_Nav_Menu and add a custom button to the submenu. How can I check for class "browse all"?
In my code I'm creating a wrapper for ul.sub-menu. I need to check if there is a "browse all" class in the element in order to add a button to this wrapper. Such a button will only be in items with the "browse all" class.
class My_Walker extends Walker_Nav_Menu {
function start_lvl( & $output, $depth = 0, $args = array()) {
$indent = str_repeat("\t", $depth);
if ($depth == 0) {
$output. = "\n$indent<div class='sub-menu__depth-1'><ul class='sub-menu sub-menu__main'>\n";
} else {
$output. = "\n$indent<ul class='sub-menu'>\n";
}
}
function end_lvl( & $output, $depth = 0, $args = array()) {
$indent = str_repeat("\t", $depth);
if ($depth == 0) {
$output. = "$indent</ul> <
/div>\n";
} else {
$output. = "$indent</ul>\n";
}
}
}
Below is an example of how it should be:
class My_Walker extends Walker_Nav_Menu
{
function start_lvl(&$output, $depth = 0, $args = array())
{
$indent = str_repeat("\t", $depth);
if ($depth == 0) {
$output .= "\n$indent<div class='sub-menu__depth-1'><ul class='sub-menu sub-menu__main'>\n";
} else {
$output .= "\n$indent<ul class='sub-menu'>\n";
}
}
function end_lvl(&$output, $depth = 0, $args = array())
{
$indent = str_repeat("\t", $depth);
if ($depth == 0) {
//here, a button appears outside the sub-menu if the navigation element has the class "browse all"
$output .= "$indent</ul>
<a>Browse All</a>
</div>\n";
} else {
$output .= "$indent</ul>\n";
}
}
}

Answer 1

I don't think you can do that directly in start_lvl or end_level - because those only create the wrapping UL. But that one doesn't have the classes you are looking for, those are on the actual navigation items, and those are processed/rendered in start_el and end_el.
But I suppose you could add a property to the class, an array - and in that one you keep the info, whether the current (sub-)menu of the specific depth requires these additional elements to be added, or not.
class My_Walker extends Walker_Nav_Menu {
private $needsCustomButtons = [];
function start_lvl( & $output, $depth = 0, $args = array()) {
$this->needsCustomButtons[$depth] = false;
// rest of the stuff that needs doing here
}
public function start_el( &$output, $data_object, $depth = 0, $args = null, $current_object_id = 0 ) {
// stuff
$classes = empty( $menu_item->classes ) ? array() : (array) $menu_item->classes;
$classes[] = 'menu-item-' . $menu_item->ID;
if(in_array('browse-all', $classes)) {
$this->needsCustomButtons[$depth] = true;
}
// more stuff here
}
function end_lvl( & $output, $depth = 0, $args = array()) {
// if $this->needsCustomButtons[$depth] is true here, then you know
// your two extra nav items need adding, so concatenate them to
// $output here, before the closing `</li>` tag gets added.
}
}