I need help with the following error:

> Fatal error: Call to a member function getno_cart_button() on a
> non-object in
> /var/home/hifi-studio_at/www/app/design/frontend/default/theme582/template/catalog/product/compare/list.phtml
> on line 134

This error occurs only in the compare-list. I made an Attribute called "no_cart_button", if it is checked, the product does not show the "Cart-Button" any more, but instead a "Anfrage (Ask)" linking to a Contact-Page. On all other lists and grids it does work. But why no here?
This is the code I used:

    <!-- // Warenkorb in Anfrage verändern // Start // -->
                    <?php 	if($_product->getno_cart_button()){ ?> <div class="add-to-cart"><button type="button" title="<?php echo $this->__('Anfrage') ?>" class="button btn-cart" onClick="parent.location='/kontakt'"><span><span><?php echo $this->__('Anfrage') ?></span></span></button></div> <?php }
                                        	else { ?> <p><button type="button" title="<?php echo Mage::helper('core')->quoteEscape($this->__('Add to Cart')) ?>" class="button btn-cart" onclick="setPLocation('<?php echo $this->helper('catalog/product_compare')->getAddToCartUrl($_item) ?>', true)"><span><span><?php echo $this->__('Add to Cart') ?></span></span></button></p> <?php } ?>
                    <?php else: ?>
                    <!-- // Warenkorb in Anfrage verändern // ENDE // -->

This Error also occurs only with Products that have this attribute. Others don't show the cart button nor the error.

Any suggestions? Thanks!

This is the full code:

    <?php
/**
 * Magento
 *
 * NOTICE OF LICENSE
 *
 * This source file is subject to the Academic Free License (AFL 3.0)
 * that is bundled with this package in the file LICENSE_AFL.txt.
 * It is also available through the world-wide-web at this URL:
 * http://opensource.org/licenses/afl-3.0.php
 * If you did not receive a copy of the license and are unable to
 * obtain it through the world-wide-web, please send an email
 * to [email protected] so we can send you a copy immediately.
 *
 * DISCLAIMER
 *
 * Do not edit or add to this file if you wish to upgrade Magento to newer
 * versions in the future. If you wish to customize Magento for your
 * needs please refer to http://www.magento.com for more information.
 *
 * @category    design
 * @package     rwd_default
 * @copyright   Copyright (c) 2006-2015 X.commerce, Inc. (http://www.magento.com)
 * @license     http://opensource.org/licenses/afl-3.0.php  Academic Free License (AFL 3.0)
 */
/* @var $this Mage_Catalog_Block_Product_Compare_List */
?>
<div class="page-title title-buttons">
    <h1><?php echo $this->__('Compare Products') ?></h1>
    <a href="#" onclick="window.print(); return false;" class="link-print"><?php echo $this->__('Print This Page') ?></a>
</div>
<?php $_total=$this->getItems()->count() ?>
<?php if($_total): ?>
    <table class="data-table compare-table" id="product_comparison">
        <?php $_i=0 ?>
        <?php foreach($this->getItems() as $_item): ?>
            <?php if($_i++%10==0): ?>
                <col width="1" />
            <?php endif; ?>
            <col width="<?php echo floor(100/$_total); ?>%" />
        <?php endforeach; ?>
        <?php if ($_total>2): ?>
            <thead>
            <tr>
                <?php $_i=0 ?>
                <?php foreach($this->getItems() as $_item): ?>
                    <?php if($_i++%10==0): ?>
                        <th>&nbsp;</th>
                    <?php endif; ?>
                    <td class="a-right"><a href="#" class="btn-remove" onclick="removeItem('<?php echo $this->helper('catalog/product_compare')->getRemoveUrl($_item) ?>');" title="<?php echo $this->quoteEscape($this->__('Remove This Item')) ?>"><?php echo $this->__('Remove This Item') ?></a></td>
                <?php endforeach; ?>
            </tr>
            </thead>
        <?php endif ?>
        <tbody>
        <tr class="product-shop-row top">
            <?php $_i=0 ?>
            <?php foreach($this->getItems() as $_item): ?>
                <?php if($_i++%10==0): ?>
                    <th>&nbsp;</th>
                <?php endif; ?>
                <td>
                    <a class="product-image" href="#" onclick="setPLocation('<?php echo $this->getProductUrl($_item) ?>', true)" title="<?php echo $this->stripTags($_item->getName(), null, true) ?>"><img src="<?php echo $this->helper('catalog/image')->init($_item, 'small_image')->resize(125, 125); ?>" width="125" height="125" alt="<?php echo $this->stripTags($_item->getName(), null, true) ?>" /></a>
                    <h2 class="product-name"><a href="#" onclick="setPLocation('<?php echo $this->getProductUrl($_item) ?>', true)" title="<?php echo $this->stripTags($_item->getName(), null, true) ?>"><?php echo $this->helper('catalog/output')->productAttribute($_item, $_item->getName(), 'name') ?></a></h2>
                    <?php echo $this->getReviewsSummaryHtml($_item, 'short') ?>
                    <?php echo $this->getPriceHtml($_item, true, '-compare-list-top') ?>
                </td>
            <?php endforeach; ?>
        </tr>
        <tr class="product-shop-row bottom">
            <?php $_i=0 ?>
            <?php foreach($this->getItems() as $_item): ?>
                <?php if($_i++%10==0): ?>
                    <th>&nbsp;</th>
                <?php endif; ?>
                <td>
                    <?php if($_item->isSaleable()): ?>
						<!-- // Warenkorb in Anfrage verändern // START // -->
                        <?php 	if($_product->getno_cart_button()){ ?> <p><button type="button" title="<?php echo $this->__('Anfrage') ?>" class="button btn-cart" onClick="parent.location='/kontakt'"><span><span><?php echo $this->__('Anfrage') ?></span></span></button></p> <?php }
								else { ?> <button type="button" title="<?php echo $this->__('Add to Cart') ?>" class="button btn-cart" onclick="setLocation('<?php echo $this->getAddToCartUrl($_product) ?>')"><span><span><?php echo $this->__('Add to Cart') ?></span></span></button> <?php } ?>
                        <?php else: ?>
						<!-- // Warenkorb in Anfrage verändern // ENDE // -->
                        <p class="availability out-of-stock"><span><?php echo $this->__('Out of stock') ?></span></p>
                    <?php endif; ?>
                    <?php if ($this->helper('wishlist')->isAllow()) : ?>
                        <ul class="add-to-links">
                            <li><a href="<?php echo $this->getAddToWishlistUrl($_item) ?>" class="link-wishlist"><?php echo $this->__('Add to Wishlist') ?></a></li>
                        </ul>
                    <?php endif; ?>
                </td>
            <?php endforeach; ?>
        </tr>
        </tbody>
        <tbody>
        <?php foreach ($this->getAttributes() as $_attribute): ?>
            <tr>
                <?php $_i=0 ?>
                <?php foreach($this->getItems() as $_item): ?>
                    <?php if($_i++%10==0): ?>
                        <th><span class="nobr"><?php echo $_attribute->getStoreLabel() ?></span></th>
                    <?php endif; ?>
                    <td>
                        <?php switch ($_attribute->getAttributeCode()) {
                            case "price": ?>
                                <?php echo $this->getPriceHtml($_item, true, '-compare-list-' . $_attribute->getCode()) ?>
                                <?php break;
                            case "small_image": ?>
                                <img src="<?php echo $this->helper('catalog/image')->init($_item, 'small_image')->resize(125, 125); ?>" width="125" height="125" alt="<?php echo $this->escapeHtml($_item->getName()) ?>" title="<?php echo $this->escapeHtml($_item->getName()) ?>" />
                                <?php break;
                            case "date":
                                echo substr($this->getProductAttributeValue($_item, $_attribute),0,10);
                                break;
                            default: ?>
                                <div class="std">
                                    <?php echo $this->helper('catalog/output')->productAttribute($_item, $this->getProductAttributeValue($_item, $_attribute), $_attribute->getAttributeCode()) ?>
                                </div>
                            <?php break;
                        } ?>
                    </td>
                <?php endforeach; ?>
            </tr>
        <?php endforeach; ?>
        </tbody>
        <tbody>
        <tr class="add-to-row">
            <?php $_i=0 ?>
            <?php foreach($this->getItems() as $_item): ?>
                <?php if($_i++%10==0): ?>
                    <th>&nbsp;</th>
                <?php endif; ?>
                <td>
                    <?php echo $this->getPriceHtml($_item, true, '-compare-list-bottom') ?>
                    <!-- // Warenkorb in Anfrage verändern // START // -->
                        <?php 	if($_product->getno_cart_button()){ ?> <p><button type="button" title="<?php echo $this->__('Anfrage') ?>" class="button btn-cart" onClick="parent.location='/kontakt'"><span><span><?php echo $this->__('Anfrage') ?></span></span></button></p> <?php }
								else { ?> <button type="button" title="<?php echo $this->__('Add to Cart') ?>" class="button btn-cart" onclick="setLocation('<?php echo $this->getAddToCartUrl($_product) ?>')"><span><span><?php echo $this->__('Add to Cart') ?></span></span></button> <?php } ?>
                        <?php else: ?>
					<!-- // Warenkorb in Anfrage verändern // ENDE // -->
                        <p class="availability out-of-stock"><span><?php echo $this->__('Out of stock') ?></span></p>
                    <?php endif; ?>
                    <?php if ($this->helper('wishlist')->isAllow()) : ?>
                        <ul class="add-to-links">
                            <li><a href="<?php echo $this->getAddToWishlistUrl($_item);?>" class="link-wishlist"><?php echo $this->__('Add to Wishlist') ?></a></li>
                        </ul>
                    <?php endif; ?>
                </td>
            <?php endforeach; ?>
        </tr>
        </tbody>
    </table>
    <div class="buttons-set">
        <button type="button" title="<?php echo $this->quoteEscape($this->__('Close Window')) ?>" class="button" onclick="window.close();"><span><span><?php echo $this->__('Close Window') ?></span></span></button>
        <span class="please-wait" id="compare-list-please-wait" style="display:none;">
            <img src="<?php echo $this->getSkinUrl('images/opc-ajax-loader.gif') ?>" alt="<?php echo $this->quoteEscape($this->__('Please wait...')) ?>" title="<?php echo $this->quoteEscape($this->__('Please wait...')) ?>" class="v-middle" /> <?php echo $this->__('Please wait...') ?>
        </span>
    </div>
    <script type="text/javascript">
        decorateTable('product_comparison');

        /**
         * Send remove item request, after that reload windows
         */
        function removeItem(url)
        {
            new Ajax.Request(url, {
                parameters: {isAjax: 1, method: 'POST'},
                onLoading: function(){$('compare-list-please-wait').show();},
                onSuccess: function(transport) {
                    $('compare-list-please-wait').hide();
                    window.location.reload();
                    window.opener.location.reload();
                }
            });
        }
    </script>
<?php else: ?>
    <script type="text/javascript">window.close();</script>
<?php endif; ?>