이것은 현재 메뉴 항목의 하위 항목 만 표시하는 데 사용 된 워커입니다. 또는 자체 자식이없는 메뉴 항목 형제입니다.
수업 내내 각 섹션을 설명하는 의견이 있습니다
<?php
class SH_Child_Only_Walker extends Walker_Nav_Menu {
private $ID;
private $depth;
private $classes = array();
private $child_count = 0;
private $have_current = false;
// Don't start the top level
function start_lvl(&$output, $depth=0, $args=array()) {
if( 0 == $depth || $this->depth != $depth )
return;
parent::start_lvl($output, $depth,$args);
}
// Don't end the top level
function end_lvl(&$output, $depth=0, $args=array()) {
if( 0 == $depth || $this->depth != $depth )
return;
parent::end_lvl($output, $depth,$args);
}
// Don't print top-level elements
function start_el(&$output, $item, $depth=0, $args=array()) {
$is_current = in_array('current-menu-item', $this->classes);
if( 0 == $depth || ! $is_current )
return;
parent::start_el($output, $item, $depth, $args);
}
function end_el(&$output, $item, $depth=0, $args=array()) {
if( 0 == $depth )
return;
parent::end_el($output, $item, $depth, $args);
}
// Only follow down one branch
function display_element( $element, &$children_elements, $max_depth, $depth=0, $args, &$output ) {
// Check if element is in the current tree to display
$current_element_markers = array( 'current-menu-item', 'current-menu-parent', 'current-menu-ancestor' );
$this->classes = array_intersect( $current_element_markers, $element->classes );
// If element has a 'current' class, it is an ancestor of the current element
$ancestor_of_current = !empty($this->classes);
// check if the element is the actual page element we are on.
$is_current = in_array('current-menu-item', $this->classes);
// if it is the current element
if($is_current) {
// set the count / ID / and depth to use in the other functions.
$this->child_count = ( isset($children_elements[$element->ID]) ) ? count($children_elements[$element->ID]) : 0;
$this->ID = $element->ID;
$this->depth = $depth;
$this->have_current = true;
if($this->child_count > 0) {
// if there are children loop through them and display the kids.
foreach( $children_elements[$element->ID] as $child ) {
parent::display_element( $child, $children_elements, $max_depth, $depth, $args, $output );
}
} else {
// no children so loop through kids of parent item.
foreach( $children_elements[$element->menu_item_parent] as $child ) {
parent::display_element( $child, $children_elements, $max_depth, $depth, $args, $output );
}
}
}
// if depth is zero and not in current tree go to the next element
if ( 0 == $depth && !$ancestor_of_current)
return;
// if we aren't on the current element proceed as normal
if(! $this->have_current )
parent::display_element( $element, $children_elements, $max_depth, $depth, $args, $output );
}
}
wp_nav_menu에서 다른 사용자 정의 워커와 같이 첨부하십시오.
<?php
wp_nav_menu( array(
'menu' => 'primary-menu'
,'container' => 'nav'
,'container_class' => 'subpages'
,'depth' => 0
,'walker' => new SH_Child_Only_Walker()
));
?>