WordPress 添加自定义文章类型的存档页面到菜单

/**
 * WordPress 添加自定义文章类型的存档页面到菜单
 * https://www.wpdaxue.com/add-custom-post-types-archive-to-nav-menus.html
 */
if( !class_exists('CustomPostTypeArchiveInNavMenu') ) {
	class CustomPostTypeArchiveInNavMenu {
		function CustomPostTypeArchiveInNavMenu() {
			add_action( 'admin_head-nav-menus.php', array( &$this, 'cpt_navmenu_metabox' ) );
			add_filter( 'wp_get_nav_menu_items', array( &$this,'cpt_archive_menu_filter'), 10, 3 );
		}
		function cpt_navmenu_metabox() {
			add_meta_box( 'add-cpt', __('自定义文章类型存档'), array( &$this, 'cpt_navmenu_metabox_content' ), 'nav-menus', 'side', 'default' );
		}
		function cpt_navmenu_metabox_content() {
			$post_types = get_post_types( array( 'show_in_nav_menus' => true, 'has_archive' => true ), 'object' );
			if( $post_types ) {
				foreach ( $post_types as &$post_type ) {
					$post_type->classes = array();
					$post_type->type = $post_type->name;
					$post_type->object_id = $post_type->name;
					$post_type->title = $post_type->labels->name . __( '存档' );
					$post_type->object = 'cpt-archive';
				}
				$walker = new Walker_Nav_Menu_Checklist( array() );
				echo '<div id="cpt-archive" class="posttypediv">';
				echo '<div id="tabs-panel-cpt-archive" class="tabs-panel tabs-panel-active">';
				echo '<ul id="ctp-archive-checklist" class="categorychecklist form-no-clear">';
				echo walk_nav_menu_tree( array_map('wp_setup_nav_menu_item', $post_types), 0, (object) array( 'walker' => $walker) );
				echo '</ul>';
				echo '</div><!-- /.tabs-panel -->';
				echo '</div>';
				echo '<p class="button-controls">';
				echo '<span class="add-to-menu">';
				echo '<input type="submit"' . disabled( $nav_menu_selected_id, 0 ) . ' class="button-secondary submit-add-to-menu right" value="'. __('添加至菜单') . '" name="add-ctp-archive-menu-item" id="submit-cpt-archive" />';
				echo '<span class="spinner"></span>';
				echo '</span>';
				echo '</p>';
			} else {
				echo '没有自定义文章类型';
			}
		}
		function cpt_archive_menu_filter( $items, $menu, $args ) {
			foreach( $items as &$item ) {
				if( $item->object != 'cpt-archive' ) continue;
				$item->url = get_post_type_archive_link( $item->type );
				if( get_query_var( 'post_type' ) == $item->type ) {
					$item->classes[] = 'current-menu-item';
					$item->current = true;
				}
			}
			return $items;
		}
	}
	$CustomPostTypeArchiveInNavMenu = new CustomPostTypeArchiveInNavMenu();
}

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