在树结构magento中打印类别

Question

我使用以下代码在树形结构中打印类别，但它没有打印任何内容..它没有显示任何类别或子类别。

这是我的代码：

       <!-- List all categories and their second level subcategories -->
       <div class="block block-list block-categories">
    <div id="block-categories" class="block-title active">
    <strong><span>Categories </span></strong>
    </div>

 <div id="leftnav" class="block-content" style="display:block">
<?php $helper = $this->helper('catalog/category') ?>
<?php $categories = $this->getStoreCategories() ?>
<?php if (count($categories) > 0): ?>
    <ul id="leftnav-tree" class="level0">
        <?php foreach($categories as $category): ?>
            <li class="level0<?php if ($this->isCategoryActive($category)): ?> active<?php endif; ?>">
               <a href="<?php echo $helper->getCategoryUrl($category) ?>"><span><?php echo $this->escapeHtml($category->getName()) ?></span></a>
                <?php //if ($this->isCategoryActive($category)): ?>
                    <?php $subcategories = $category->getChildren() ?>
                    <?php if (count($subcategories) > 0): ?>
                        <ul id="leftnav-tree-<?php echo $category->getId() ?>" class="level1">
                            <?php foreach($subcategories as $subcategory): ?>
                                <li class="level1<?php if ($this->isCategoryActive($subcategory)): ?> active<?php endif; ?>">
                                    <a href="<?php echo $helper->getCategoryUrl($subcategory) ?>"><?php echo $this->escapeHtml(trim($subcategory->getName(), '- ')) ?></a>
                                     <?php $secondLevelSubcategories = $subcategory->getChildren() ?>
                                     <?php if (count($secondLevelSubcategories ) > 0): ?>
                        <ul id="leftnav-tree-<?php echo $subcategory->getId() ?>" class="level2">
                            <?php foreach($secondLevelSubcategories as $secondLevelSubcategory ): ?>
                                <li class="level2<?php if ($this->isCategoryActive($secondLevelSubcategory )): ?> active<?php endif; ?>">
                                    <a href="<?php echo $helper->getCategoryUrl($secondLevelSubcategory ) ?>"><?php echo $this->escapeHtml(trim($secondLevelSubcategory ->getName(), '- ')) ?></a>
                                </li>
                                <?php endforeach; ?>
                        </ul>
                        <script type="text/javascript">decorateList('leftnav-tree-<?php echo $category->getId() ?>', 'recursive')</script>
                    <?php endif; ?>
                            <?php endforeach; ?>
                        </ul>
                        <script type="text/javascript">decorateList('leftnav-tree-<?php echo $category->getId() ?>', 'recursive')</script>
                    <?php endif; ?>
                <?php //endif; ?>
            </li>
        <?php endforeach; ?>
    </ul>
    <script type="text/javascript">decorateList('leftnav-tree', 'recursive')</script>
<?php endif; ?>
 </div>
  </div>

任何人都可以帮我打印树形结构中的类别。 提前谢谢。