由于博客使用的是LayUI框架，在使用二级导航时，发现wordpress的wp_nav_menu()输出与LayUI自带的导航样式不搭配，因此只能稍微改造了一下wp_nav_menu()的输出方式。
functions.php 写入
class new_walker extends Walker_Nav_Menu{ //修改一级ul标签样式 function start_lvl( &$output, $depth = 0, $args = array() ){ if( $depth == 0 ){ $output .= '<ul class="layui-nav-child">'; }else{ $output .= '<ul class="layui-nav-child">'; } } function end_lvl( &$output, $depth = 0, $args = array() ){ if( $depth == 0 ){ $output .= "</ul>"; }else{ $output .= '</ul>'; } } function start_el( &$output, $item, $depth = 0, $args = array(), $id = 0 ) { 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; $args = apply_filters( 'nav_menu_item_args', $args, $item, $depth ); $class_names = join( ' ', apply_filters( 'nav_menu_css_class', array_filter( $classes ), $item, $args, $depth ) ); if( $depth == 0 ){ $class_names .= ' layui-nav-item'; //增加Layui样式 } if ( in_array( 'current-menu-item', $classes ) ){ $class_names .= ' layui-this'; //增加当前样式 } $class_names = $class_names ? ' class="' . esc_attr( $class_names ) . '"' : ''; $id = apply_filters( 'nav_menu_item_id', 'menu-item-' . $item->ID, $item, $args, $depth ); $id = $id ? ' id="' . esc_attr( $id ) . '"' : ''; $output .= $indent . '<li' . $id . $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 noreferrer'; } else { $atts['rel'] = $item->xfn; } $atts['href'] = ! empty( $item->url ) ? $item->url : ''; $atts['aria-current'] = $item->current ? 'page' : ''; $atts = apply_filters( 'nav_menu_link_attributes', $atts, $item, $args, $depth ); $attributes = ''; foreach ( $atts as $attr => $value ) { if ( ! empty( $value ) ) { $value = ( 'href' === $attr ) ? esc_url( $value ) : esc_attr( $value ); $attributes .= ' ' . $attr . '="' . $value . '"'; } } $title = apply_filters( 'the_title', $item->title, $item->ID ); $title = apply_filters( 'nav_menu_item_title', $title, $item, $args, $depth ); $item_output = $args->before; $item_output .= '<a' . $attributes . '>'; $item_output .= $args->link_before . $title . $args->link_after; $item_output .= '</a>'; $item_output .= $args->after; $output .= apply_filters( 'walker_nav_menu_start_el', $item_output, $item, $depth, $args ); } }这样就可以愉快的使用wordpress的菜单功能了。
