How to include second layer sub menu to Walker Nav?

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I need to be able to access the sub-menus of the sub-menus on my nav. Currently I'm only able to access the first sub-menu layer. What do I need to add to access these?

<?php


class Walker_Nav_Primary extends Walker_Nav_Menu {

    function start_lvl( &$output, $depth = 0, $args = array() )  // ul
    {
        $indent = str_repeat("\t", $depth);
        $submenu = ($depth > 0) ? 'sub-menu' : '';
        $output .="\n$indent<ul class=\"submenu-first $submenu depth_$depth\">\n";
    }

  
    function start_el( &$output, $item, $depth = 0, $args = array(), $id = 0 ){ //li a span
        
        $indent = ( $depth ) ? str_repeat("\t",$depth) : '';
        
        $li_attributes = '';
        $class_names = $value = '';
        
        $classes = empty( $item->classes ) ? array() : (array) $item->classes;
        
        $classes[] = ($args->walker->has_children) ? 'has_sub' : '';
        $classes[] = ($item->current || $item->current_item_ancestor) ? 'active' : '';
        $classes[] = 'menu-item-' . $item->ID;
        if( $depth && $args->walker->has_children ){
            $classes[] = 'dropdown-submenu';
        }

        $class_names =  join(' ', apply_filters('nav_menu_css_class', array_filter( $classes ), $item, $args ) );
        $class_names = ' class="' . esc_attr($class_names) . '"';

        $id = apply_filters('nav_menu_item_id', 'menu-item-'.$item->ID, $item, $args);
        $id = strlen( $id ) ? ' id="' . esc_attr($id) . '"' : "";
        $output .= $indent . '<li' . $id . $value . $class_names . $li_attributes . '>';

        $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) . '"' : '';
        
        $attributes .= ( $args->walker->has_children ) ? ' class="has_sub_link" data-toggle="has_sub_link"' : '';
        
        $item_output = $args->before;
        $item_output .= '<a' . $attributes . '>';
        $item_output .= $args->link_before . apply_filters( 'the_title', $item->title, $item->ID ) . $args->link_after;
        $item_output .= ( $depth == 0 && $args->walker->has_children ) ? ' <b class="caret"></b></a>' : '</a>';
        $item_output .= $args->after;
        
        $output .= apply_filters ( 'walker_nav_menu_start_el', $item_output, $item, $depth, $args );
    }
}

I need to be able to access the sub-menus of the sub-menus on my nav. Currently I'm only able to access the first sub-menu layer. What do I need to add to access these?

<?php


class Walker_Nav_Primary extends Walker_Nav_Menu {

    function start_lvl( &$output, $depth = 0, $args = array() )  // ul
    {
        $indent = str_repeat("\t", $depth);
        $submenu = ($depth > 0) ? 'sub-menu' : '';
        $output .="\n$indent<ul class=\"submenu-first $submenu depth_$depth\">\n";
    }

  
    function start_el( &$output, $item, $depth = 0, $args = array(), $id = 0 ){ //li a span
        
        $indent = ( $depth ) ? str_repeat("\t",$depth) : '';
        
        $li_attributes = '';
        $class_names = $value = '';
        
        $classes = empty( $item->classes ) ? array() : (array) $item->classes;
        
        $classes[] = ($args->walker->has_children) ? 'has_sub' : '';
        $classes[] = ($item->current || $item->current_item_ancestor) ? 'active' : '';
        $classes[] = 'menu-item-' . $item->ID;
        if( $depth && $args->walker->has_children ){
            $classes[] = 'dropdown-submenu';
        }

        $class_names =  join(' ', apply_filters('nav_menu_css_class', array_filter( $classes ), $item, $args ) );
        $class_names = ' class="' . esc_attr($class_names) . '"';

        $id = apply_filters('nav_menu_item_id', 'menu-item-'.$item->ID, $item, $args);
        $id = strlen( $id ) ? ' id="' . esc_attr($id) . '"' : "";
        $output .= $indent . '<li' . $id . $value . $class_names . $li_attributes . '>';

        $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) . '"' : '';
        
        $attributes .= ( $args->walker->has_children ) ? ' class="has_sub_link" data-toggle="has_sub_link"' : '';
        
        $item_output = $args->before;
        $item_output .= '<a' . $attributes . '>';
        $item_output .= $args->link_before . apply_filters( 'the_title', $item->title, $item->ID ) . $args->link_after;
        $item_output .= ( $depth == 0 && $args->walker->has_children ) ? ' <b class="caret"></b></a>' : '</a>';
        $item_output .= $args->after;
        
        $output .= apply_filters ( 'walker_nav_menu_start_el', $item_output, $item, $depth, $args );
    }
}

• menus
• walker

Share Improve this question asked Oct 14, 2021 at 16:12 RRhodesRRhodes 10533 bronze badges

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1 Answer 1

Sorted by: Reset to default 0

Without testing & debugging your example I'm not 100% certain what's going wrong. I noticed your walker doesn't have a end_lvl method which would be my first guess as to why dropdowns past the first level won't work.

Here's a copy of a Nav Walker that I'm certain handles nested nav menus well. You'll want to replace the start_el contents with those from your example.

<?php
class Walker_Nav_Primary extends Walker_Nav_Menu {


    function start_lvl( &$output, $depth = 0, $args = array() ) {
        $indent = str_repeat("\t", $depth);
        $output .= "\n<ul class=\"sub-menu\">\n";
    }

    function end_lvl( &$output, $depth = 0, $args = array() ) {
        $indent = str_repeat("\t", $depth);
        $output .= "</ul>\n";
    }

    function start_el( &$output, $item, $depth = 0, $args = array(), $id = 0 ) {
        $indent = ( $depth ) ? str_repeat( "\t", $depth ) : '';

        $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 ) );

        $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 . '';

        $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 .= '<li'. $class_names .'><a'. $attributes .'>';
        $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 .= "\n";
    }
}

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