Построение дерева многоуровневого меню

 Здесь рассмотрен вариант создания меню из альбомов модуля Gallery, но можно использовать и в других случаях, убрав лишние конструкции и заменив ссылки в элементах.

<?php
//Set options for sideGalleri

$galleryId = $modx->getOption('galleryId', $scriptProperties, 5);
$itemClass = $modx->getOption('itemClass', $scriptProperties, '');
$wrapperClass = $modx->getOption('wrapperClass', $scriptProperties, '');
$dropdownWrapperClass = $modx->getOption('dropdownWrapperClass', $scriptProperties, '');

$arrConfig = array(
    'galleryId' => $galleryId,
    'itemClass' => $itemClass,
    'wrapperClass' => $wrapperClass,
    'dropdownWrapperClass' => $dropdownWrapperClass
);

if(!function_exists('view_album')) {
    function view_album($modx, $arrConfig, $data, $iteration) {
        $arr = "";
        $iteration = isset($iteration) ? $iteration : 0;
        ++$iteration;
        
        foreach ($data as $menu) {
    	    if(!empty($menu['childs'])) {
    	        $arr .= '<li class="' . $arrConfig['itemClass'] . ' ' . $menu['galleri-active'] . '"><a href="' . $modx->makeUrl($arrConfig['galleryId']) . '?galAlbum=' . $menu['id'] . '">' . $menu['name'] . '</a>';
    	        $arr .= view_album($modx, $arrConfig, $menu['childs'], $iteration) . '</li>';
    	    }else{
                $arr .= '<li class="' . $arrConfig['itemClass'] . ' ' . $menu['galleri-active'] . '"><a href="' . $modx->makeUrl($arrConfig['galleryId']) . '?galAlbum=' . $menu['id'] . '">' . $menu['name'] . '</a></li>';  	        
    	    }
        }
        if($iteration > 1) {
            return '<ul class="' . $arrConfig['dropdownWrapperClass'] . ' ' . $active . '">' . $arr . '</ul>';
        }else{
            return '<ul class="' . $arrConfig['wrapperClass'] . ' ' . $active . '">' . $arr . '</ul>';
        }
    }
}

if(!function_exists("map_tree")) {
    function map_tree($row) {
        $tree = array();
        $currAlbum = $_GET['galAlbum'];
        
        foreach ($row as $k => &$v) {
            if (!$v['parent']) {
                $tree[$k] = &$v;
            }else{
                $row[$v['parent']]['childs'][$k] = &$v;
            }
        }
        return $tree;
    }
}
if(!function_exists("checkActive")) {
    function checkActive(&$row, $currAlbum) {
        $row[$currAlbum]['galleri-active'] = 'active';
        if($row[$currAlbum]['parent']) {
            checkActive($row, $row[$currAlbum]['parent']);
        }
    }
}

$stmt = $modx->query("SELECT * FROM modx_gallery_albums");
$row = $stmt->fetchAll(PDO::FETCH_ASSOC);
$data = array();
foreach($row as $k => $v) {
    $data[$v['id']] = $v;
}

$currAlbum = $_GET['galAlbum'];
checkActive($data, $currAlbum);
$allMenu = map_tree($data);

return view_album($modx, $arrConfig, $allMenu, $iteration);
/*echo "<pre>";
print_r($allMenu);*/