Is it possible to find out what page a post is contained in?
Im in my single.php template and im listing child pages in a sidebar using wp_list_pages, I want the page (not category) that the post is visible in to be highlighted, or add current_page_item to it, is this possible? It works everywhere else at the moment except for the single.php template.
$ancestors = array();
$ancestors = get_ancestors($post->ID,'page');
$parent = (!empty($ancestors)) ? array_pop($ancestors) : $post->ID;
$parent should be the topmost page parent.
However, if you are using a WordPress generated menu there is a pretty good chance that there is already a item identified by a CSS class as the parent. Take a good look at the generated markup.
http://codex.wordpress.org/Function_Reference/wp_nav_menu#Menu_Item_CSS_Classes
Note: using wp_list_pages, for nested pages, current_page_parent applies to the immediate parent only but current_page_ancestor is applied to all of the parent pages. That is the class you want (I think). Just adjust your CSS.
