HTML/CSS dropdown menu into WordPress dynamic menu - php

Question

I'm converting the static HTML/CSS menu into the WordPress menu, it works fine for me in case there's no dropdown, no child menu but I want to make changes in code so I could work fine even for the dropdown menu, now in my case, if I put dropdown menu using WordPress menu, it breaks website header design.
Into Header.php
<?php wp_nav_menu(array(
'menu' => 'HeaderMenu',
'menu_class' => 'navbar-nav mr-auto',
'container' => '',
'li_class' => 'nav-item',
'a_class' => 'nav-link',
'active_class' =>'active' ,
)); ?>
Into Functions.php
register_nav_menus(array(
'HeaderMenu' => __( 'Header Menu', 'theme')
));
function add_class_li($classes, $item, $args){
if(isset($args-> li_class)){
$classes[] = $args->li_class;
}
if(isset($args-> active_class) && in_array('current-menu-item', $classes)){
$classes[] = $args->active_class;
}
return $classes;
}
add_filter('nav_menu_css_class', 'add_class_li',10,3);
function add_anchor_class($attr, $item, $args){
if(isset($args-> a_class)){
$attr['class'] = $args->a_class;
}return $attr;
}
add_filter('nav_menu_link_attributes', 'add_anchor_class',10,3);
HTML/CSS CODE
<ul class="navbar-nav mr-auto">
<li class="nav-item active">
<a class="nav-link" href="index.html">HOME<span class="sr-only">(current)</span></a> </li>
<li class="nav-item">
<a class="nav-link" href="about.html">ABOUT</a></li>
<li class="nav-item">
<a class="nav-link" href="service.html">SERVICES</a></li>
<li class="#" href="#">
<a class="nav-link" href="blog.html">BLOG</a></li>
<li class="nav-item" href="#">
<a class="nav-link" href="contact.html">CONTACT</a></li>
<li class="last"><img src="images/search-icon.png" alt="icon"></li>
</ul>

Answer 1

Add this custom nav Walker class in you theme's functions.php
class Custom_Nav_Walker extends Walker_Nav_Menu
{
/**
* #var array $menu_items
*/
private $menu_items;
/**
* #var int $last_menu_id
*/
private $last_menu_id;
/**
* #var int $first_menu_id
*/
private $first_menu_id;
/**
* #inheritdoc
*/
public function start_el( &$output, $item, $depth = 0, $args = null, $id = 0 ) {
if( is_null( $this->menu_items ) ) {
$this->menu_items = wp_get_nav_menu_items( $args->theme_location );
if( $this->menu_items != false ) {
$first_menu_index = array_key_first( $this->menu_items );
$last_menu_index = array_key_last( $this->menu_items );
$this->first_menu_id = $this->menu_items[ $first_menu_index ]->ID;
$this->last_menu_id = $this->menu_items[ $last_menu_index ]->ID;
}
}
if ( isset( $args->item_spacing ) && 'discard' === $args->item_spacing ) {
$t = '';
$n = '';
} else {
$t = "\t";
$n = "\n";
}
$indent = ( $depth ) ? str_repeat( $t, $depth ) : '';
$classes = empty( $item->classes ) ? array() : (array) $item->classes;
$classes[] = 'menu-item-' . $item->ID;
/**
* Filters the arguments for a single nav menu item.
*
* #since 4.4.0
*
* #param stdClass $args An object of wp_nav_menu() arguments.
* #param WP_Post $item Menu item data object.
* #param int $depth Depth of menu item. Used for padding.
*/
$args = apply_filters( 'nav_menu_item_args', $args, $item, $depth );
/**
* Filters the CSS classes applied to a menu item's list item element.
*
* #since 3.0.0
* #since 4.1.0 The `$depth` parameter was added.
*
* #param string[] $classes Array of the CSS classes that are applied to the menu item's `<li>` element.
* #param WP_Post $item The current menu item.
* #param stdClass $args An object of wp_nav_menu() arguments.
* #param int $depth Depth of menu item. Used for padding.
*/
$class_names = apply_filters( 'nav_menu_css_class', array_filter( $classes ), $item, $args, $depth );
$custom_menu_class = [ 'nav-item' ];
if( in_array( 'current-menu-item', $class_names ) ) {
$custom_menu_class[] = 'active';
}
$class_names = implode( ' ', $custom_menu_class);
if( $item->ID == $this->last_menu_id ) {
$class_names = ' class="last"';
} else {
$class_names = $class_names ? ' class="' . esc_attr( $class_names ) . '"' : '';
}
$output .= $indent . '<li' . $class_names . '>';
$atts = array();
$atts['title'] = ! empty( $item->attr_title ) ? $item->attr_title : '';
$atts['target'] = ! empty( $item->target ) ? $item->target : '';
if ( '_blank' === $item->target && empty( $item->xfn ) ) {
$atts['rel'] = 'noopener';
} else {
$atts['rel'] = $item->xfn;
}
$atts['href'] = ! empty( $item->url ) ? $item->url : '';
$atts['aria-current'] = $item->current ? 'page' : '';
/**
* Filters the HTML attributes applied to a menu item's anchor element.
*
* #since 3.6.0
* #since 4.1.0 The `$depth` parameter was added.
*
* #param array $atts {
* The HTML attributes applied to the menu item's `<a>` element, empty strings are ignored.
*
* #type string $title Title attribute.
* #type string $target Target attribute.
* #type string $rel The rel attribute.
* #type string $href The href attribute.
* #type string $aria_current The aria-current attribute.
* }
* #param WP_Post $item The current menu item.
* #param stdClass $args An object of wp_nav_menu() arguments.
* #param int $depth Depth of menu item. Used for padding.
*/
$atts = apply_filters( 'nav_menu_link_attributes', $atts, $item, $args, $depth );
$attributes = '';
foreach ( $atts as $attr => $value ) {
if ( is_scalar( $value ) && '' !== $value && false !== $value ) {
$value = ( 'href' === $attr ) ? esc_url( $value ) : esc_attr( $value );
$attributes .= ' ' . $attr . '="' . $value . '"';
}
}
/** This filter is documented in wp-includes/post-template.php */
$title = apply_filters( 'the_title', $item->title, $item->ID );
/**
* Filters a menu item's title.
*
* #since 4.4.0
*
* #param string $title The menu item's title.
* #param WP_Post $item The current menu item.
* #param stdClass $args An object of wp_nav_menu() arguments.
* #param int $depth Depth of menu item. Used for padding.
*/
$title = apply_filters( 'nav_menu_item_title', $title, $item, $args, $depth );
if( $item->ID == $this->last_menu_id ) {
$item_output = '<img src="images/search-icon.png" alt="icon">';
} else if ( $item->ID == $this->first_menu_id ) {
$item_output = $args->before;
$item_output .= '<a' . $attributes . '>';
$item_output .= $args->link_before . $title . '<span class="sr-only">(current)</span>';
$item_output .= '</a>';
$item_output .= $args->after;
} else {
$item_output = $args->before;
$item_output .= '<a' . $attributes . '>';
$item_output .= $args->link_before . $title . $args->link_after;
$item_output .= '</a>';
$item_output .= $args->after;
}
/**
* Filters a menu item's starting output.
*
* The menu item's starting output only includes `$args->before`, the opening `<a>`,
* the menu item's title, the closing `</a>`, and `$args->after`. Currently, there is
* no filter for modifying the opening and closing `<li>` for a menu item.
*
* #since 3.0.0
*
* #param string $item_output The menu item's starting HTML output.
* #param WP_Post $item Menu item data object.
* #param int $depth Depth of menu item. Used for padding.
* #param stdClass $args An object of wp_nav_menu() arguments.
*/
$output .= apply_filters( 'walker_nav_menu_start_el', $item_output, $item, $depth, $args );
}
}
and then add this class into wp_nav_menu via walker argument.
wp_nav_menu(
array(
'theme_location' => 'your theme location',
'echo' => true,
'walker' => new Custom_Nav_Walker(),
'menu_class' => 'navbar-nav mr-auto'
)
);
also no need to add any extra filter for menu classes.