Magento: getAttributeText('manufacturer') doesn't work

Question

I would very much appreciate your help. I am new to Magento and exploring it's possibilities. I have this piece of code, which loads products from category and their attributes:

<?php
    $_productCollection=$this->getLoadedProductCollection();
    $_helper = $this->helper('catalog/output');
?>

<?php if(!$_productCollection->count()): ?>
<p class="note-msg"><?php echo $this->__('There are no products matching the selection.') ?></p>
<?php else: ?>
<div class="category-products">
     <?php // Grid Mode ?>
    <?php $_collectionSize = $_productCollection->count() ?>
    <?php $_columnCount = $this->getColumnCount(); ?>
        <?php $_iterator = 0; ?>
        <ul class="products-grid">    
        <?php $i=0; foreach ($_productCollection as $_product): ?>
            <li class="item">
                <a href="<?php echo $_product->getProductUrl() ?>" title="<?php echo $this->stripTags($this->getImageLabel($_product, 'small_image'), null, true) ?>" class="product-image"><img src="<?php echo $this->helper('catalog/image')->init($_product, 'small_image')->resize(252); ?>" width="252" height="252" alt="<?php echo $this->stripTags($this->getImageLabel($_product, 'small_image'), null, true) ?>" /></a>
                <h3 class="product-name"><a href="<?php echo $_product->getProductUrl() ?>" title="<?php echo $this->stripTags($_product->getName(), null, true) ?>"><?php echo $_helper->productAttribute($_product, $_product->getName(), 'name') ?></a></h3>
                <h4 class="product-name"><?php echo $_product->getAttributeText('manufacturer') ?></h4>                
                <?php echo $this->getPriceHtml($_product, true) ?>
             </li>  
        <?php endforeach ?>
        </ul>
        <script type="text/javascript">decorateGeneric($$('ul.products-grid'), ['odd','even','first','last'])</script>
</div>
<?php endif; ?>

My question is: why "echo $_product->getAttributeText('manufacturer')" is not working here? I have tried countless variants with different code, but the manufacturer parameter just doesn't show up. Do you know why?

Solution

I have tried what Adam Moss has suggested and it worked:

'Show in Product Listing' needed to be set to yes in the attribute editor in admin. Then echo $_product->getAttributeText('manufacturer') worked without any problems.

Comments

[Adam Moss]

Also ensure that 'Show in Product Listing' is set to yes in the attribute editor.

[ahnbizcad]

I set "used in product listing" to "yes", and it doesn't seem to pull

[Shawn Northrop]

I could not get this to work either, however, if I use $_product->getData('manufacturer') it seems to work