<?$i=0; foreach ($categories as $_category){ if($_category->hasChildren()){ $i++;?>
<select id="id<?=$_category->getId();?>" class="pa left1 top6" onchange="document.getElementById('HiddenField').value=this.options[this.selectedIndex].value;" style="visibility: <?if($i==1) echo 'visible'; else echo 'hidden';?>">
<?foreach($_category->getChildren() as $subcategory){ if($subcategory->getIsActive()){?>
<option title="<?=$subcategory->getName();?>" value="<?=$subcategory->getId();?>" >
</option>
<?}}?>
</select>
<?}}?>
<input type="hidden" id="HiddenField" name="category" value="" />