php Wordpress菜单/导航----将.active类添加到活动菜单项---- Bootstrap Nav Walker

Posted 2021-05-04

<?php

/**
 * Class Name: wp_bootstrap_navwalker
 * GitHub URI: https://github.com/twittem/wp-bootstrap-navwalker
 * Description: A custom WordPress nav walker class to implement the Bootstrap 3 navigation style in a custom theme using the WordPress built in menu manager.
 * Version: 2.0.4
 * Author: Edward McIntyre - @twittem
 * License: GPL-2.0+
 * License URI: http://www.gnu.org/licenses/gpl-2.0.txt
 */

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() ) {
    $indent = str_repeat( "\t", $depth );
    $output .= "\n$indent<ul role=\"menu\" class=\" dropdown-menu\">\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 ( 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;
    }
  }
}

// ----------------------------------------
//  wp_nav_menu with no containers
// ----------------------------------------
<?php 
  $defaults = array(
    'theme_location'  => 'main-nav',
    'container'       => false,
    'echo'            => true,
    'items_wrap'      => '<ul class="nav navbar-nav">%3$s</ul>',
    'depth'           => 1,
  );
  wp_nav_menu( $defaults );
?>

// ----------------------------------------
//  Add .active class to active menu items
// ----------------------------------------

add_filter('nav_menu_css_class' , 'special_nav_class' , 10 , 2);
function special_nav_class($classes, $item){
  if( in_array('current-menu-item', $classes) ){
    $classes[] = 'active ';
  }
  return $classes;
}

// -------------------------------
//  Basic code
// -------------------------------

<?php

$defaults = array(
	'theme_location'  => '',
	'menu'            => '',
	'container'       => 'div',
	'container_class' => '',
	'container_id'    => '',
	'menu_class'      => 'menu',
	'menu_id'         => '',
	'echo'            => true,
	'fallback_cb'     => 'wp_page_menu',
	'before'          => '',
	'after'           => '',
	'link_before'     => '',
	'link_after'      => '',
	'items_wrap'      => '<ul id="%1$s" class="%2$s">%3$s</ul>',
	'depth'           => 0,
	'walker'          => ''
);

wp_nav_menu( $defaults );

?>

// -------------------------------
//  With Bootstrap 3
// -------------------------------

<nav class="navbar navbar-default navbar-static-top mobile-nav" role="navigation">
  <div class="container">
    
    <div class="navbar-header">
      <a href="#" id="main-mobile-nav-toggle" data-toggle="collapse" data-target="#main-mobile-nav">
        <span>Menu</span>
        <button type="button" class="navbar-toggle">
          <span class="sr-only">Toggle navigation</span>
          <span class="icon-bar"></span>
          <span class="icon-bar"></span>
          <span class="icon-bar"></span>
        </button>
      </a>
    </div>


    <?php

    $defaults = array(
      'theme_location'  => 'primary-mobile',
      'menu'            => '',
      'container'       => 'div',
      'container_class' => 'navbar-collapse collapse',
      'container_id'    => 'main-mobile-nav',
      'menu_class'      => 'menu',
      'echo'            => true,
      'fallback_cb'     => 'wp_page_menu',
      'items_wrap'      => '<ul class="nav navbar-nav">%3$s</ul>',
      'depth'           => 0,
    );

    wp_nav_menu( $defaults );

    ?>

  </div><!-- /.container -->
</nav>

// -------------------------------------------
//  With Bootstrap 3 + Custom Walker (Basic)
// -------------------------------------------

// Instructions: https://github.com/twittem/wp-bootstrap-navwalker

// Important! Include the following line in functions.php:
require_once('wp_bootstrap_navwalker.php');

<?php /* Primary navigation */
  wp_nav_menu( array(
    'menu' => 'top_menu',
    'depth' => 2,
    'container' => false,
    'menu_class' => 'nav navbar-nav',
    //Process nav menu using our custom nav walker
    'walker' => new wp_bootstrap_navwalker())
  );
?>


// -------------------------------------------------
//  With Bootstrap 3 + Custom Walker (Full Markup)
// -------------------------------------------------  
	        
<div class="row">
  <nav class="col-md-10 col-md-offset-1" id="main-nav">
    <div class="navbar-header">
      <button type="button" class="navbar-toggle" data-toggle="collapse" data-target=".navbar-collapse">
        <span class="sr-only">Toggle navigation</span>
        <span class="icon-bar"></span>
        <span class="icon-bar"></span>
        <span class="icon-bar"></span>
      </button>
    </div>
    <div class="navbar-collapse ">
      <?php /* Primary navigation */
      wp_nav_menu( array(
        'menu' => 'top_menu',
        'depth' => 2,
        'container' => false,
        'menu_class' => 'nav navbar-nav',
        //Process nav menu using our custom nav walker
        'walker' => new wp_bootstrap_navwalker())
      );
      ?>
    </div>
  </nav>
</div>


// -------------------------------
//  Page Menu
// -------------------------------

<?php $args = array(
  'depth'       => 0,
  'sort_column' => 'menu_order, post_title',
  'menu_class'  => 'menu-mobile',
  'include'     => '',
  'exclude'     => '',
  'echo'        => true,
  'show_home'   => false,
  'link_before' => '',
  'link_after'  => '<span class="icon-left-arrow"></span><span class="icon-down-arrow"></span>' );
?>
<?php wp_page_menu( $args ); ?>