Modifying wp_bootstrap_navwalker to work as a mega menu WordPress

dimadin answers:

1) Is this class after you have modified it to meet your needs or before?

2) I am not sure that I understand how your menu should look like, lets try:

- row 1: items Home, Services
- row 2: items Service 1, Service 2
- row 3: items Children, Children

In other words, no any form of dropdown, everything is shown immediately.

---

---

Rempty answers:

I made the modifications, this is for 2 columns, max 3 with some additions,
Need this css

<style>
.dropdown-menu {
min-width: 200px;
}
.dropdown-menu.columns-2 {
min-width: 400px;
}
.dropdown-menu.columns-3 {
min-width: 600px;
}
.dropdown-menu li a {
padding: 5px 15px;
font-weight: 300;
}
.multi-column-dropdown {
list-style: none;
}
.multi-column-dropdown li a {
display: block;
clear: both;
line-height: 1.428571429;
color: #333;
white-space: normal;
}
.multi-column-dropdown li a:hover {
text-decoration: none;
color: #262626;
background-color: #f5f5f5;
}

@media (max-width: 767px) {
.dropdown-menu.multi-column {
min-width: 240px !important;
overflow-x: hidden;
}
}
</style>

And this modified class

class wp_bootstrap_navwalker extends Walker_Nav_Menu {

/**
* @see Walker::start_lvl()
* @since 3.0.0
*
* @param string $output Passed by reference. Used to append additional content.
* @param int $depth Depth of page. Used for padding.
*/
public function start_lvl( &$output, $depth = 0, $args = array() ) {
if($depth==0){
$output .= "<ul role=\"menu\" class=\"dropdown-menu multi-column columns-2\">\n";
}
else{
$output .= "<ul role=\"menu\" class=\"multi-column-dropdown\">\n";
}
}


/**
* @see Walker::start_el()
* @since 3.0.0
*
* @param string $output Passed by reference. Used to append additional content.
* @param object $item Menu item data object.
* @param int $depth Depth of menu item. Used for padding.
* @param int $current_page Menu item ID.
* @param object $args
*/
public function start_el( &$output, $item, $depth = 0, $args = array(), $id = 0 ) {
$indent = ( $depth ) ? str_repeat( "\t", $depth ) : '';

/**
* Dividers, Headers or Disabled
* =============================
* Determine whether the item is a Divider, Header, Disabled or regular
* menu item. To prevent errors we use the strcasecmp() function to so a
* comparison that is not case sensitive. The strcasecmp() function returns
* a 0 if the strings are equal.
*/
if ( strcasecmp( $item->attr_title, 'divider' ) == 0 && $depth === 1 ) {
$output .= $indent . '<li role="presentation" class="divider">';
} else if ( strcasecmp( $item->title, 'divider') == 0 && $depth === 1 ) {
$output .= $indent . '<li role="presentation" class="divider">';
} else if ( strcasecmp( $item->attr_title, 'dropdown-header') == 0 && $depth === 1 ) {
$output .= $indent . '<li role="presentation" class="dropdown-header">' . esc_attr( $item->title );
} else if ( strcasecmp($item->attr_title, 'disabled' ) == 0 ) {
$output .= $indent . '<li role="presentation" class="disabled"><a href="#">' . esc_attr( $item->title ) . '</a>';
} else {

$class_names = $value = '';

$classes = empty( $item->classes ) ? array() : (array) $item->classes;
$classes[] = 'menu-item-' . $item->ID;

$class_names = join( ' ', apply_filters( 'nav_menu_css_class', array_filter( $classes ), $item, $args ) );

if ( $args->has_children )
$class_names .= ' dropdown';
if ( $args->has_children && $depth==1)
$class_names .= ' dropdown col-md-6';
if ( in_array( 'current-menu-item', $classes ) )
$class_names .= ' active';

$class_names = $class_names ? ' class="' . 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 .'>';

$atts = array();
$atts['title'] = ! empty( $item->title ) ? $item->title : '';
$atts['target'] = ! empty( $item->target ) ? $item->target : '';
$atts['rel'] = ! empty( $item->xfn ) ? $item->xfn : '';

// If item has_children add atts to a.
if ( $args->has_children && $depth === 0 ) {
$atts['href'] = '#';
$atts['data-toggle'] = 'dropdown';
$atts['class'] = 'dropdown-toggle';
$atts['aria-haspopup'] = 'true';
} else {
$atts['href'] = ! empty( $item->url ) ? $item->url : '';
}

$atts = apply_filters( 'nav_menu_link_attributes', $atts, $item, $args );

$attributes = '';
foreach ( $atts as $attr => $value ) {
if ( ! empty( $value ) ) {
$value = ( 'href' === $attr ) ? esc_url( $value ) : esc_attr( $value );
$attributes .= ' ' . $attr . '="' . $value . '"';
}
}

$item_output = $args->before;

/*
* Glyphicons
* ===========
* Since the the menu item is NOT a Divider or Header we check the see
* if there is a value in the attr_title property. If the attr_title
* property is NOT null we apply it as the class name for the glyphicon.
*/
if ( ! empty( $item->attr_title ) )
$item_output .= '<a'. $attributes .'><span class="glyphicon ' . esc_attr( $item->attr_title ) . '"></span>&nbsp;';
else
$item_output .= '<a'. $attributes .'>';

$item_output .= $args->link_before . apply_filters( 'the_title', $item->title, $item->ID ) . $args->link_after;
$item_output .= ( $args->has_children && 0 === $depth ) ? ' <span class="caret"></span></a>' : '</a>';
$item_output .= $args->after;

$output .= apply_filters( 'walker_nav_menu_start_el', $item_output, $item, $depth, $args );
}
}

/**
* Traverse elements to create list from elements.
*
* Display one element if the element doesn't have any children otherwise,
* display the element and its children. Will only traverse up to the max
* depth and no ignore elements under that depth.
*
* This method shouldn't be called directly, use the walk() method instead.
*
* @see Walker::start_el()
* @since 2.5.0
*
* @param object $element Data object
* @param array $children_elements List of elements to continue traversing.
* @param int $max_depth Max depth to traverse.
* @param int $depth Depth of current element.
* @param array $args
* @param string $output Passed by reference. Used to append additional content.
* @return null Null on failure with no changes to parameters.
*/
public function display_element( $element, &$children_elements, $max_depth, $depth, $args, &$output ) {
if ( ! $element )
return;

$id_field = $this->db_fields['id'];

// Display this element.
if ( is_object( $args[0] ) )
$args[0]->has_children = ! empty( $children_elements[ $element->$id_field ] );

parent::display_element( $element, $children_elements, $max_depth, $depth, $args, $output );
}

/**
* Menu Fallback
* =============
* If this function is assigned to the wp_nav_menu's fallback_cb variable
* and a manu has not been assigned to the theme location in the WordPress
* menu manager the function with display nothing to a non-logged in user,
* and will add a link to the WordPress menu manager if logged in as an admin.
*
* @param array $args passed from the wp_nav_menu function.
*
*/
public static function fallback( $args ) {
if ( current_user_can( 'manage_options' ) ) {

extract( $args );

$fb_output = null;

if ( $container ) {
$fb_output = '<' . $container;

if ( $container_id )
$fb_output .= ' id="' . $container_id . '"';

if ( $container_class )
$fb_output .= ' class="' . $container_class . '"';

$fb_output .= '>';
}

$fb_output .= '<ul';

if ( $menu_id )
$fb_output .= ' id="' . $menu_id . '"';

if ( $menu_class )
$fb_output .= ' class="' . $menu_class . '"';

$fb_output .= '>';
$fb_output .= '<li><a href="' . admin_url( 'nav-menus.php' ) . '">Add a menu</a></li>';
$fb_output .= '</ul>';

if ( $container )
$fb_output .= '</' . $container . '>';

echo $fb_output;
}
}
}


For 3 columns

//Find this line
<ul role=\"menu\" class=\"dropdown-menu multi-column columns-2\">
//change to
<ul role=\"menu\" class=\"dropdown-menu multi-column columns-3\">

//And
$class_names .= ' dropdown col-md-6';
//To
$class_names .= ' dropdown col-md-4';