Question

I have a menu with two levels, the second level shown in the secondary menu.

How can I open the second menu level programmatically from pages other than those linked in the menu?

I’ve looked at theme_preprocess_page and others but can’t figure out how the change the menu item state from collapsed to active.

Answer 1

Answering my own question, this node api hook does it.
Inspired by the Menu Trails module, Mike mentioned.

function phptemplate_nodeapi(&$node, $op) {
  if($open_menu_for_this_node && $op == 'view') {
    $item = menu_get_item();
    $item['href'] = $menu_item_to_open;
    menu_set_item(NULL, $item);
  }
}