I’m trying to create a mega menu walker. Unfortunately, walkers completely escape my coding knowledge. I could really use some help getting it working. Here’s the features I need:
- Wrap the second-level
<ul>in<section>. [COMPLETE] - When a user sets the class “break” on an
<li>in the second level<ul>, make that<li>the start a new<ul>. If it’s the first<li>in the list, don’t do anything, to prevent the formation of empty unordered lists. [COMPLETE] - When a user sets the class “widget” on an
<li>in the first level that has a sub<ul>, append a widget to the end of that<ul>. [COMPLETE] - Add class
mega-menu-columns-#to first level<li>elements that contain drop downs with multiple columns and/or a widget. The # represents the number of<ul>elements, +1 for the widget if it exists. [COMPLETE]
I have a bit of code to do some of this, but not all of it. There are cut-out sections below:
Wrap second level <ul> in <section>:
function start_lvl(&$output, $depth = 0, $args = array()) {
if ($depth == 0) {
$output .= "<section>";
}
$output .= "<ul class=\"sub-menu\">";
}
function end_lvl(&$output, $depth = 0, $args = array()) {
$output .= "</ul>";
if ($depth == 0) {
$output .= "</section>\n";
}
}
Generate the widget HTML:
ob_start();
dynamic_sidebar("Navigation Callout");
$widget = ob_get_contents();
ob_end_clean();
The output HTML would be:
<ul>
<li id="menu-item-1" class="menu-item menu-item-type-post_type menu-item-object-page menu-item-has-children menu-item-1 mega-menu-columns-2">
<a href="http://www.example.com/about/">
About Us
</a>
<section>
<ul class="sub-menu">
<li id="menu-item-2" class="menu-item menu-item-type-post_type menu-item-object-page menu-item-2">
<a href="http://www.example.com/about/company-profile/">
Company Profile
</a>
</li>
<li id="menu-item-3" class="menu-item menu-item-type-post_type menu-item-object-page menu-item-3">
<a href="http://www.example.com/about/leadership-team/">
Leadership Team
</a>
</li>
<li id="menu-item-4" class="menu-item menu-item-type-post_type menu-item-object-page menu-item-4">
<a href="http://www.example.com/about/professional-affiliations/">
Professional Affiliations
</a>
</li>
</ul>
<ul class="sub-menu">
<li id="menu-item-5" class="break menu-item menu-item-type-post_type menu-item-object-page menu-item-5">
<a href="http://www.example.com/about/clients/">
Clients
</a>
</li>
<li id="menu-item-6" class="menu-item menu-item-type-post_type menu-item-object-page menu-item-6">
<a href="http://www.example.com/about/partnerships/">
Partnerships
</a>
</li>
</ul>
</section>
</li>
<li id="menu-item-7" class="widget menu-item menu-item-type-post_type menu-item-object-page menu-item-has-children menu-item-7 mega-menu-columns-3">
<a href="http://www.example.com/services/">
Services
</a>
<section>
<ul class="sub-menu">
<li id="menu-item-8" class="menu-item menu-item-type-post_type menu-item-object-page menu-item-8">
<a href="http://www.example.com/services/civil-engineering/">
Civil Engineering
</a>
</li>
<li id="menu-item-9" class="menu-item menu-item-type-post_type menu-item-object-page menu-item-9">
<a href="http://www.example.com/services/land-planning/">
Land Planning
</a>
</li>
<li id="menu-item-10" class="menu-item menu-item-type-post_type menu-item-object-page menu-item-10">
<a href="http://www.example.com/services/surveying/">
Surveying
</a>
</li>
</ul>
<ul class="sub-menu">
<li id="menu-item-11" class="break menu-item menu-item-type-post_type menu-item-object-page menu-item-11">
<a href="http://www.example.com/services/information-technology/">
Information Technology
</a>
</li>
<li id="menu-item-12" class="menu-item menu-item-type-post_type menu-item-object-page menu-item-12">
<a href="http://www.example.com/services/subsurface-utility-engineering/">
Subsurface Utility Engineering
</a>
</li>
</ul>
<aside>
<h6>Widget Title</h6>
<p>Maecenas quis semper arcu. Quisque consequat risus nisi. Sed venenatis urna porta eros malesuada euismod. Nulla sollicitudin fringilla posuere. Nulla et tellus eu nisi sodales convallis non vel tellus.</p>
</aside>
</section>
</li>
<li id="menu-item-13" class="menu-item menu-item-type-post_type menu-item-object-page menu-item-15">
<a href="http://www.example.com/contact/">
Contact Us
</a>
</li>
</ul>
UPDATE: My counters are giving me grief. They’re only counting after the sub menu’s been generated, which doesn’t help me. See this screenshot to understand what I mean:
The top numbers are being pulled in start_el. The bottom numbers are being pulled in end_el. As you can see, the top numbers aren’t counting my .breaks as they should. They count the widget class because those are being counted in $depth = 0. Someone please save me from this horribleness!
// mega menu walker
/*
ONE REMAINING BUG:
- Need to add class to LI containing mega-menu-columns-#
*/
class megaMenuWalker extends Walker_Nav_Menu {
private $column_limit = 3; /* needs to be set for each site */
private $show_widget = false;
private $column_count = 0;
static $li_count = 0;
function start_el(&$output, $item, $depth = 0, $args = array(), $id = 0) {
$classes = empty($item->classes) ? array() : (array) $item->classes;
$item_id = $item->ID;
if ($depth == 0) self::$li_count = 0;
if ($depth == 0 && in_array("widget", $classes)) {
$this->show_widget = true;
$this->column_count++;
}
if ($depth == 1 && self::$li_count == 1) {
$this->column_count++;
}
if ($depth == 1 && in_array("break", $classes) && self::$li_count != 1 && $this->column_count < $this->column_limit) {
$output .= "</ul><ul class=\"sub-menu\">";
$this->column_count++;
}
if ($depth == 0 && $this->column_count > 0) {
$mega_menu_class = " mega-menu-columns-" . $this->column_count;
}
$class_names = join(" ", apply_filters("nav_menu_css_class", array_filter($classes), $item));
$class_names = " class=\"" . esc_attr($class_names . $mega_menu_class) . "\"";
$output .= sprintf(
"<li id=\"menu-item-%s\"%s><a href=\"%s\">%s</a>",
$item_id,
$class_names,
$item->url,
$item->title
);
self::$li_count++;
}
function start_lvl(&$output, $depth = 0, $args = array()) {
if ($depth == 0) {
$output .= "<section>";
}
$output .= "<ul class=\"sub-menu\">";
}
function end_lvl(&$output, $depth = 0, $args = array()) {
$output .= "</ul>";
if ($depth == 0) {
if ($this->show_widget) {
ob_start();
dynamic_sidebar("Navigation Callout");
$widget = ob_get_contents();
ob_end_clean();
$output .= $widget;
$this->show_widget = false;
}
$output .= "</section>";
}
}
function end_el(&$output, $item, $depth = 0, $args = array(), $id = 0) {
if ($depth == 0 && $this->column_count > 0) {
/* needs to be added to opening level 0 li */
$column_count_class = " mega-menu-columns-" . $this->column_count;
$output .= $column_count_class;
/* end */
$this->column_count = 0;
}
$output .= "</li>";
}
}
UPDATE 2: Here’s an example of output with comments describing how the mega-menu-columns- class should count things:
<ul>
<!-- +1 because this has a class of "widget" -->
<li id="menu-item-1" class="widget menu-item menu-item-type-post_type menu-item-object-page menu-item-has-children menu-item-1 mega-menu-columns-3">
<a href="http://www.example.com/about/">
About Us
</a>
<!-- +1 because a drop down exists -->
<!-- gets added by my walker -->
<section>
<!-- end gets added by my walker -->
<ul class="sub-menu">
<!-- +0 because this "break" is the first child -->
<li id="menu-item-2" class="break menu-item menu-item-type-post_type menu-item-object-page menu-item-2">
<a href="http://www.example.com/about/company-profile/">
Company Profile
</a>
<ul>
<!-- +0 because this "break" is in level 2 -->
<li id="menu-item-3" class="break menu-item menu-item-type-post_type menu-item-object-page menu-item-3">
<a href="http://www.example.com/about/our-team/">
Our Team
</a>
</li>
</ul>
</li>
<li id="menu-item-4" class="menu-item menu-item-type-post_type menu-item-object-page menu-item-4">
<a href="http://www.example.com/about/leadership-team/">
Leadership Team
</a>
</li>
<li id="menu-item-5" class="menu-item menu-item-type-post_type menu-item-object-page menu-item-5">
<a href="http://www.example.com/about/professional-affiliations/">
Professional Affiliations
</a>
</li>
<!-- gets added by my walker -->
</ul>
<ul class="sub-menu">
<!-- end gets added by my walker -->
<!-- +1 because this "break" is in level 1 and not the first child -->
<li id="menu-item-6" class="break menu-item menu-item-type-post_type menu-item-object-page menu-item-6">
<a href="http://www.example.com/about/clients/">
Clients
</a>
</li>
<li id="menu-item-7" class="menu-item menu-item-type-post_type menu-item-object-page menu-item-7">
<a href="http://www.example.com/about/partnerships/">
Partnerships
</a>
</li>
</ul>
<!-- gets added by my walker for .widget -->
<section>
<header>
<h1>Widget Title</h1>
</header>
<p>This is a widget. It was hard to make appear!</p>
</section>
<!-- end gets added by my walker for .widget -->
<!-- gets added by my walker -->
</section>
<!-- end gets added by my walker -->
</li>
</ul>
UPDATE: Here’s my final Walker and Functions. This does exactly what I wanted it to. Thanks for the help!
// mega menu walker
class megaMenuWalker extends Walker_Nav_Menu {
private $column_limit = 3;
private $show_widget = false;
private $column_count = 0;
static $li_count = 0;
function start_el(&$output, $item, $depth = 0, $args = array(), $id = 0) {
$classes = empty($item->classes) ? array() : (array) $item->classes;
$item_id = $item->ID;
if ($depth == 0) {
self::$li_count = 0;
}
if ($depth == 0 && in_array("widget", $classes)) {
$this->show_widget = true;
$this->column_count++;
}
if ($depth == 1 && self::$li_count == 1) {
$this->column_count++;
}
if ($depth == 1 && in_array("break", $classes) && self::$li_count != 1 && $this->column_count < $this->column_limit) {
$output .= "</ul><ul class=\"sub-menu\">";
$this->column_count++;
}
$class_names = join(" ", apply_filters("nav_menu_css_class", array_filter($classes), $item)); // set up the classes array to be added as classes to each li
$class_names = " class=\"" . esc_attr($class_names) . "\"";
$output .= sprintf(
"<li id=\"menu-item-%s\"%s><a href=\"%s\">%s</a>",
$item_id,
$class_names,
$item->url,
$item->title
);
self::$li_count++;
}
function start_lvl(&$output, $depth = 0, $args = array()) {
if ($depth == 0) {
$output .= "<section>";
}
$output .= "<ul class=\"sub-menu\">";
}
function end_lvl(&$output, $depth = 0, $args = array()) {
$output .= "</ul>";
if ($depth == 0) {
if ($this->show_widget) {
ob_start();
dynamic_sidebar("Navigation Callout");
$widget = ob_get_contents();
ob_end_clean();
$output .= $widget;
$this->show_widget = false;
}
$output .= "</section>";
}
}
function end_el(&$output, $item, $depth = 0, $args = array(), $id = 0) {
if ($depth == 0 && $this->column_count > 0) {
$this->column_count = 0;
}
$output .= "</li>";
}
}
// add mega-menu-columns-# classes
function add_column_number($items, $args) {
static $column_limit = 3;
static $post_id = 0;
static $x_key = 0;
static $column_count = 0;
static $li_count = 0;
$tmp = array();
foreach($items as $key => $item) {
if (0 == $item->menu_item_parent) {
$x_key = $key;
$post_id = $item->ID;
$column_count = 0;
$li_count = 0;
if (in_array("widget", $item->classes, 1)) {
$column_count++;
}
}
if ($post_id == $item->menu_item_parent) {
$li_count++;
if ($column_count < $column_limit && $li_count == 1) {
$column_count++;
}
if (in_array("break", $item->classes, 1) && $li_count > 1 && $column_count < $column_limit) {
$column_count++;
}
$tmp[$x_key] = $column_count;
}
}
foreach($tmp as $key => $value) {
$items[$key]->classes[] = sprintf("mega-menu-columns-%d", $value);
}
unset($tmp);
return $items;
};
// add the column classes
add_filter("wp_nav_menu_args", function($args) {
if ($args["walker"] instanceof megaMenuWalker) {
add_filter("wp_nav_menu_objects", "add_column_number");
}
return $args;
});
// stop the column classes function
add_filter("wp_nav_menu", function( $nav_menu ) {
remove_filter("wp_nav_menu_objects", "add_column_number");
return $nav_menu;
});
1
If I understand the problem setup correctly, you could try to do the break and widget class counting within the wp_nav_menu_objects filter.
Here’s an updated example, it’s rather expanded because of the extra debug part:
add_filter( 'wp_nav_menu_objects',
function( $items, $args ) {
// Only apply this for the 'primary' menu:
if( 'primary' !== $args->theme_location )
return $items;
// Here "x_" means the latest root li (depth 0)
static $x_pid = 0; // post ID of the latest root li (depth 0)
static $x_key = 0; // array key of the latest root li (depth 0)
static $x_cols = 0; // n breaks or widgets gives n+1 columns
static $x_has_dropdown = false; // if the latest root li (depth 0) has dropdown
// Internals:
$tmp = array();
$debug_string = '';
$show_debug = true; // Edit this to your needs:
foreach( $items as $key => $item )
{
// Debug:
$debug = array();
$debug['ID'] = $item->ID;
$debug['title'] = $item->title;
$debug['key'] = $key;
$debug['x_key'] = $x_key;
$debug['depth'] = '';
$debug['menu_item_parent'] = $item->menu_item_parent;
$debug['has_widget_class'] = 0;
$debug['is_depth_1_first_child'] = 0;
$debug['x_has_dropdown'] = 0;
$debug['has_break_class'] = 0;
$debug['x_cols_increase'] = 0;
// Collect columns increaments:
$inc = 0;
// Depth 0:
if( 0 == $item->menu_item_parent )
{
$debug['depth'] = 0;
// Resets:
$x_key = $key;
$x_pid = $item->ID;
$x_cols = 0;
$x_has_dropdown = false;
// If widget class exists:
if( in_array( 'widget', $item->classes, 1 ) )
{
$debug['has_widget_class'] = '1';
$inc++;
}
}
// Depth 1:
if( $x_pid == $item->menu_item_parent )
{
$debug['depth'] = 1;
// Increase the columns count for an existing dropdown:
if( ! $x_has_dropdown )
{
$inc++;
$x_has_dropdown = true;
}
// Check for the 'break' class:
if( in_array( 'break', $item->classes, 1 ) )
{
$debug['x_has_break_class'] = 1;
// First li child:
if( $x_key+1 == $key+0 )
{
$debug['is_depth_1_first_child'] = 1;
}
else
{
$debug['is_depth_1_first_child'] = 0;
$inc++;
}
}
$t[$x_key] = $x_cols;
}
$debug['x_has_dropdown'] = (int) $x_has_dropdown;
// Increase the columns count:
$debug['x_cols_increase'] = $inc;
$x_cols += $inc;
$debug['x_cols'] = $x_cols;
// Collect the debug:
$debug_string .= print_r( $debug, 1 );
} // end foreach
// Show debug info:
if( $show_debug )
printf( "<!-- debug: %s -->", $debug_string );
// Insert the new 'mega menu' class to the corresponding menu object:
foreach( $t as $key => $value )
{
$items[$key]->classes[] = sprintf( 'mega-menu-columns-%d', $value );
}
return $items;
}
, PHP_INT_MAX, 2 );
With your current menu tree, I get this debug information:
<!-- debug: Array
(
[ID] => 3316
Mega Menu Walker => About Us
[key] => 1
[x_key] => 0
[depth] => 0
[menu_item_parent] => 0
[has_widget_class] => 1
[is_depth_1_first_child] => 0
[x_has_dropdown] => 0
[has_break_class] => 0
[x_cols_increase] => 1
[x_cols] => 1
)
Array
(
[ID] => 3317
Mega Menu Walker => Company Profile
[key] => 2
[x_key] => 1
[depth] => 1
[menu_item_parent] => 3316
[has_widget_class] => 0
[is_depth_1_first_child] => 1
[x_has_dropdown] => 1
[has_break_class] => 0
[x_cols_increase] => 1
[x_has_break_class] => 1
[x_cols] => 2
)
Array
(
[ID] => 3318
Mega Menu Walker => Our Team
[key] => 3
[x_key] => 1
[depth] =>
[menu_item_parent] => 3317
[has_widget_class] => 0
[is_depth_1_first_child] => 0
[x_has_dropdown] => 1
[has_break_class] => 0
[x_cols_increase] => 0
[x_cols] => 2
)
Array
(
[ID] => 3319
Mega Menu Walker => Leadership Team
[key] => 4
[x_key] => 1
[depth] => 1
[menu_item_parent] => 3316
[has_widget_class] => 0
[is_depth_1_first_child] => 0
[x_has_dropdown] => 1
[has_break_class] => 0
[x_cols_increase] => 0
[x_cols] => 2
)
Array
(
[ID] => 3320
Mega Menu Walker => Professional Affiliations
[key] => 5
[x_key] => 1
[depth] => 1
[menu_item_parent] => 3316
[has_widget_class] => 0
[is_depth_1_first_child] => 0
[x_has_dropdown] => 1
[has_break_class] => 0
[x_cols_increase] => 0
[x_cols] => 2
)
Array
(
[ID] => 3321
Mega Menu Walker => Clients
[key] => 6
[x_key] => 1
[depth] => 1
[menu_item_parent] => 3316
[has_widget_class] => 0
[is_depth_1_first_child] => 0
[x_has_dropdown] => 1
[has_break_class] => 0
[x_cols_increase] => 1
[x_has_break_class] => 1
[x_cols] => 3
)
Array
(
[ID] => 3322
Mega Menu Walker => Partnerships
[key] => 7
[x_key] => 1
[depth] => 1
[menu_item_parent] => 3316
[has_widget_class] => 0
[is_depth_1_first_child] => 0
[x_has_dropdown] => 1
[has_break_class] => 0
[x_cols_increase] => 0
[x_cols] => 3
)
-->
If you want to check if the walker object is of the megaMenuWalker class, you can use:
if( ! is_object( $args->walker ) || ! is_a( $args->walker, 'megaMenuWalker' ) )
return $items;
instead of
if( 'primary' !== $args->theme_location )
return $items;
I hope this helps.