Wordpress menu walker - removing class from submenu items - php

Question

I am using a custom walker for my menu which adds correct classes to parent ul/li/a elements. But, on every submenu LI and A tag i would like to remove all the styling but i cant figure out how to do it...
Any help would be greatly appreciated.
This is the code:
class CSS_Menu_Walker extends Walker {
var $db_fields = array('parent' => 'menu_item_parent', 'id' => 'db_id');
function start_lvl(&$output, $depth = 0, $args = array()) {
$indent = str_repeat("\t", $depth);
$output .= "\n$indent<ul class='sub-menu'>\n";
}
function end_lvl(&$output, $depth = 0, $args = array()) {
$indent = str_repeat("\t", $depth);
$output .= "$indent</ul>\n";
}
function start_el(&$output, $item, $depth = 0, $args = array(), $id = 0) {
global $wp_query;
$indent = ($depth) ? str_repeat("\t", $depth) : '';
$class_names = $value = '';
$classes = empty($item->classes) ? array() : (array) $item->classes;
/* Add active class */
if (in_array('current-menu-item', $classes)) {
$classes[] = 'active';
unset($classes['current-menu-item']);
}
/* Check for children */
$children = get_posts(array('post_type' => 'nav_menu_item', 'nopaging' => true, 'numberposts' => 1, 'meta_key' => '_menu_item_menu_item_parent', 'meta_value' => $item->ID));
if (!empty($children)) {
$classes[] = 'nav-item-parent';
}
$class_names = join(' ', apply_filters('nav_menu_css_class', array_filter($classes), $item, $args));
$class_names = $class_names ? ' class="nav-item ' . esc_attr($class_names) . '"' : '';
$id = apply_filters('nav_menu_item_id', 'menu-item-'. $item->ID, $item, $args);
$id = $id ? ' id="' . esc_attr($id) . '"' : '';
$output .= $indent . '<li' . $id . $value . $class_names .'>';
$attributes = ! empty($item->attr_title) ? ' title="' . esc_attr($item->attr_title) .'"' : '';
$attributes .= ! empty($item->target) ? ' target="' . esc_attr($item->target ) .'"' : '';
$attributes .= ! empty($item->xfn) ? ' rel="' . esc_attr($item->xfn ) .'"' : '';
$attributes .= ! empty($item->url) ? ' href="' . esc_attr($item->url ) .'"' : '';
$item_output = $args->before;
$item_output .= '<a'. $attributes .' class="nav-link">';
$item_output .= $args->link_before . apply_filters('the_title', $item->title, $item->ID) . $args->link_after;
$item_output .= '</a>';
$item_output .= $args->after;
$output .= apply_filters('walker_nav_menu_start_el', $item_output, $item, $depth, $args);
}
function end_el(&$output, $item, $depth = 0, $args = array()) {
$output .= "</li>\n";
}
}
This is how the code should be outputed:
<li class="nav-item"> <!-- This is done properly -->
<a href="#" class="nav-link "> <!-- This is done properly -->
Top Level Link
</a>
</li>
<li class="nav-item nav-item-parent"><!-- This is done properly -->
<a href="#" class="nav-link "> <!-- This is done properly -->
Top Level Link
</a>
<ul class="sub-menu">
<!-- LI and A get css classes from their parents (aka, nav-item and nav-link) and i dont need any classes on them -->
<li>Child Link</li>
<li>Child Link</li>
<li>Child Link</li>
</ul>
</li>

Answer 1

Using only CSS, you can target the element using its parent's class:
Example:
.nav-item ul li{
//Your css declarations
}
.nav-item ul li a{
//Your css declarations
}
Inspect the element and see what properties it gets from its parents.
For example if it gets padding of 15px from the parent, you can force to change the value:
.nav-item ul li a{
padding: 0 !important;
}
Hope it helps