function _menu_tree_data

Builds the data representing a menu tree.

The function is a bit complex because the rendering of a link depends on the next menu link.

Related topics

File

includes/menu.inc, line 1589

Code

function _menu_tree_data(&$links, $parents, $depth) {
    $tree = array();
    while ($item = array_pop($links)) {
        // We need to determine if we're on the path to root so we can later build
        // the correct active trail and breadcrumb.
        $item['in_active_trail'] = in_array($item['mlid'], $parents);
        // Add the current link to the tree.
        $tree[$item['mlid']] = array(
            'link' => $item,
            'below' => array(),
        );
        // Look ahead to the next link, but leave it on the array so it's available
        // to other recursive function calls if we return or build a sub-tree.
        $next = end($links);
        // Check whether the next link is the first in a new sub-tree.
        if ($next && $next['depth'] > $depth) {
            // Recursively call _menu_tree_data to build the sub-tree.
            $tree[$item['mlid']]['below'] = _menu_tree_data($links, $parents, $next['depth']);
            // Fetch next link after filling the sub-tree.
            $next = end($links);
        }
        // Determine if we should exit the loop and return.
        if (!$next || $next['depth'] < $depth) {
            break;
        }
    }
    return $tree;
}