Filter manufacturer and categories only on custom navigation (dual navigation)

Question

I've been working on having a two sets of layered navigation to make it easier to navigate my website. I have successfully added categories and manufacturers as a tab in the center. When I enabled price (or any other attribute) to be used in the left hand layered navigation, it became visible in the center. (See picture bellow)

The code for the center navigation:

<?php if($this->canShowBlock()): ?>
<div class="block-content">

    <?php if($this->canShowOptions()): ?>
            <?php $_filters = $this->getFilters() ?>
            <ul id="tabs">

            <?php $counterOne =0; ?>
            <?php $counterTwo =0; ?>
            <?php foreach ($_filters as $_filter): ?>
            <?php $counterOne++; ?>
            <?php if($_filter->getItemsCount()): ?>
             <li><a href="#" title="tab<?php echo $counterOne; ?>"><?php echo $this->__($_filter->getName()) ?></a></li>


            <?php endif; ?>
            <?php endforeach; ?>
            </ul>
            <div id="content"> 
             <?php foreach ($_filters as $_filter): ?>
             <?php $counterTwo++; ?>
            <?php if($_filter->getItemsCount()): ?>
                <div id="tab<?php echo $counterTwo; ?>"><?php echo $_filter->getHtml() ?></div>
            <?php endif; ?>
            <?php endforeach; ?>
       </div>
        <script type="text/javascript">decorateDataList('narrow-by-list')</script>
    <?php endif; ?>
</div>

How can I implement a filter in the above so that only the Category and Manufacturer will appear in the center layered navigation?

EDIT:

When I add:

<?php if($_filter->getName() == 'Category' || $_filter->getName() == 'Manufacturer' ): ?>

Directly bellow the first

<?php foreach ($_filters as $_filter): ?>

It works, however when I click on the Manufacturer under the manufacturer tab I receive a You cannot define a correlation name 'manufacturer_idx' more than once

Any thoughts?

EDIT What I am looking to achieve is to have Category and Manufacturer in the center while all other filterable attributes appear on the left. Is this possible?

Answer 1

You will only be able to do this hardcoded.

So filtering out the manufacturer and category on the left side and creating a custom PHTML file that generates links/dropdowns for the manufacturer and category in the center.

so in app/design/frontend/[template]/[package]/template/catalog/layer/view.phtml around line 49 edit

<?php if($_filter->getItemsCount() && ($_filter->getName()!='manufacturer' || $_filter->getName()!='categories')): ?>
   <dt><?php echo $this->__($_filter->getName()) ?></dt>
   <dd><?php echo $_filter->getHtml() ?></dd>
<?php endif; ?>

Would eliminate manufacturer and categories from the list. Optionally try to use getCode, I think that would return the attribute_code instead of the name.

For your center layered navigation create a new PHTML file and add it to the layout

<reference name="content">
   <block type="core/template" name="center_layered_nav" template="catalog/layer/center.phtml"/>
</reference>

and in the file catalog/layer/center.phtml something like this

<form method="GET" id="center_layered">
<select name="manufacturer" onchange="document.getElementById('center_layered').submit();">
<?php 
$attribute = Mage::getSingleton('eav/config')->getAttribute('catalog_product', 'manufacturer');

$options = $attribute->getSource()->getAllOptions(false);
foreach ($options as $option)
{
   echo '<option value="'.$option['value'].'">'.$option['label'].'</option>';
}
?>
</select>
</form>

when a user selects a manufacturer it should add manufacturer to the layered navigation URL. Manufacturer does have to be a filterable attribute tho.

This is highly untested code so may need a tweak or two but it's basically what you need. And I'm in no way pretending this is best practice but as far as I know it's the only way to do it.