WordPress/wp-includes/class-walker-nav-menu.php
Peter Wilson 4131900722 Menus: Add white space option to wp_nav_menu() and wp_list_pages().
Adds an `item_spacing` option to the arguments array for the functions `wp_nav_menu()`, `wp_list_pages()`, and `wp_page_menu()`. `item_spacing` is a boolean accepting either `preserve` or `discard`.

Previously, certain CSS choices could result in a site's layout changing if `wp_nav_menu()` fell back to the default `wp_list_pages()` due to differences in the whitespace within the HTML. The new argument ensures a function outputs consistant HTML while maintaining backward compatibility.

Fixes #35206.

Built from https://develop.svn.wordpress.org/trunk@38523


git-svn-id: http://core.svn.wordpress.org/trunk@38464 1a063a9b-81f0-0310-95a4-ce76da25c4cd
2016-09-06 09:06:31 +00:00

251 lines
7.5 KiB
PHP

<?php
/**
* Nav Menu API: Walker_Nav_Menu class
*
* @package WordPress
* @subpackage Nav_Menus
* @since 4.6.0
*/
/**
* Core class used to implement an HTML list of nav menu items.
*
* @since 3.0.0
*
* @see Walker
*/
class Walker_Nav_Menu extends Walker {
/**
* What the class handles.
*
* @since 3.0.0
* @access public
* @var string
*
* @see Walker::$tree_type
*/
public $tree_type = array( 'post_type', 'taxonomy', 'custom' );
/**
* Database fields to use.
*
* @since 3.0.0
* @access public
* @todo Decouple this.
* @var array
*
* @see Walker::$db_fields
*/
public $db_fields = array( 'parent' => 'menu_item_parent', 'id' => 'db_id' );
/**
* Starts the list before the elements are added.
*
* @since 3.0.0
*
* @see Walker::start_lvl()
*
* @param string $output Passed by reference. Used to append additional content.
* @param int $depth Depth of menu item. Used for padding.
* @param array $args An array of wp_nav_menu() arguments.
*/
public function start_lvl( &$output, $depth = 0, $args = array() ) {
if ( 'preserve' === $args->item_spacing ) {
$t = "\t";
$n = "\n";
} else {
$t = '';
$n = '';
}
$indent = str_repeat( $t, $depth );
$output .= "{$n}{$indent}<ul class=\"sub-menu\">{$n}";
}
/**
* Ends the list of after the elements are added.
*
* @since 3.0.0
*
* @see Walker::end_lvl()
*
* @param string $output Passed by reference. Used to append additional content.
* @param int $depth Depth of menu item. Used for padding.
* @param array $args An array of wp_nav_menu() arguments.
*/
public function end_lvl( &$output, $depth = 0, $args = array() ) {
if ( 'preserve' === $args->item_spacing ) {
$t = "\t";
$n = "\n";
} else {
$t = '';
$n = '';
}
$indent = str_repeat( $t, $depth );
$output .= "$indent</ul>{$n}";
}
/**
* Starts the element output.
*
* @since 3.0.0
* @since 4.4.0 The {@see 'nav_menu_item_args'} filter was added.
*
* @see Walker::start_el()
*
* @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 array $args An array of wp_nav_menu() arguments.
* @param int $id Current item ID.
*/
public function start_el( &$output, $item, $depth = 0, $args = array(), $id = 0 ) {
if ( 'preserve' === $args->item_spacing ) {
$t = "\t";
$n = "\n";
} else {
$t = '';
$n = '';
}
$indent = ( $depth ) ? str_repeat( $t, $depth ) : '';
$classes = empty( $item->classes ) ? array() : (array) $item->classes;
$classes[] = 'menu-item-' . $item->ID;
/**
* Filters the arguments for a single nav menu item.
*
* @since 4.4.0
*
* @param array $args An array of arguments.
* @param object $item Menu item data object.
* @param int $depth Depth of menu item. Used for padding.
*/
$args = apply_filters( 'nav_menu_item_args', $args, $item, $depth );
/**
* Filters the CSS class(es) applied to a menu item's list item element.
*
* @since 3.0.0
* @since 4.1.0 The `$depth` parameter was added.
*
* @param array $classes The CSS classes that are applied to the menu item's `<li>` element.
* @param object $item The current menu item.
* @param array $args An array of wp_nav_menu() arguments.
* @param int $depth Depth of menu item. Used for padding.
*/
$class_names = join( ' ', apply_filters( 'nav_menu_css_class', array_filter( $classes ), $item, $args, $depth ) );
$class_names = $class_names ? ' class="' . esc_attr( $class_names ) . '"' : '';
/**
* Filters the ID applied to a menu item's list item element.
*
* @since 3.0.1
* @since 4.1.0 The `$depth` parameter was added.
*
* @param string $menu_id The ID that is applied to the menu item's `<li>` element.
* @param object $item The current menu item.
* @param array $args An array of wp_nav_menu() arguments.
* @param int $depth Depth of menu item. Used for padding.
*/
$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 : '';
$atts['rel'] = ! empty( $item->xfn ) ? $item->xfn : '';
$atts['href'] = ! empty( $item->url ) ? $item->url : '';
/**
* Filters the HTML attributes applied to a menu item's anchor element.
*
* @since 3.6.0
* @since 4.1.0 The `$depth` parameter was added.
*
* @param array $atts {
* The HTML attributes applied to the menu item's `<a>` element, empty strings are ignored.
*
* @type string $title Title attribute.
* @type string $target Target attribute.
* @type string $rel The rel attribute.
* @type string $href The href attribute.
* }
* @param object $item The current menu item.
* @param array $args An array of wp_nav_menu() arguments.
* @param int $depth Depth of menu item. Used for padding.
*/
$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 . '"';
}
}
/** This filter is documented in wp-includes/post-template.php */
$title = apply_filters( 'the_title', $item->title, $item->ID );
/**
* Filters a menu item's title.
*
* @since 4.4.0
*
* @param string $title The menu item's title.
* @param object $item The current menu item.
* @param array $args An array of wp_nav_menu() arguments.
* @param int $depth Depth of menu item. Used for padding.
*/
$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 .= $args->after;
/**
* Filters a menu item's starting output.
*
* The menu item's starting output only includes `$args->before`, the opening `<a>`,
* the menu item's title, the closing `</a>`, and `$args->after`. Currently, there is
* no filter for modifying the opening and closing `<li>` for a menu item.
*
* @since 3.0.0
*
* @param string $item_output The menu item's starting HTML output.
* @param object $item Menu item data object.
* @param int $depth Depth of menu item. Used for padding.
* @param array $args An array of wp_nav_menu() arguments.
*/
$output .= apply_filters( 'walker_nav_menu_start_el', $item_output, $item, $depth, $args );
}
/**
* Ends the element output, if needed.
*
* @since 3.0.0
*
* @see Walker::end_el()
*
* @param string $output Passed by reference. Used to append additional content.
* @param object $item Page data object. Not used.
* @param int $depth Depth of page. Not Used.
* @param array $args An array of wp_nav_menu() arguments.
*/
public function end_el( &$output, $item, $depth = 0, $args = array() ) {
if ( 'preserve' === $args->item_spacing ) {
$t = "\t";
$n = "\n";
} else {
$t = '';
$n = '';
}
$output .= "</li>{$n}";
}
} // Walker_Nav_Menu