How to create next and previous product links?

Question

Question speaks for it self. I found 2 blog posts about it. Should I create my own helper class like Here or do it right in view.phtml like here. Which would be best approach and isn't there a better one?

Answer 1

Should I create my own helper class or do it right in view.phtml?

The answer is both.

You need to create a helper and then call that class form within view.phtml as described in the Inchoo article.

Both the links you've supplied are using the same code, but the one from Inchoo is the original post with the other one being a copy+paste job with some tiny modifications. Use the Inchoo code, it is the best way to implement this functionality on a standard site.

Take note of what the article says about layered navigation - this code will only work with standard categories that have 'Is Anchor' set to 'No'.

Answer 2

There is also another Previous/Next Products extension created by Branko Ajzele. You can find it on github: https://github.com/ajzele/Inchoo_Prevnext (take a look at the original Blog post)

The basic idea is to create an observer, which grabs the currently loaded product collection from product list block. So this one is actually working with layered navigation.

Answer 3

The inchoo code didn't work for me. This works though:

function getNextProductUrl($category, $currentProduct) {

    $productPositions = $category->getProductsPosition();
    asort($productPositions);
    $sortedCatProductIds = array_keys($productPositions);

    $currentProductCategoryIndex = @array_search($currentProduct->getId(), $sortedCatProductIds);

    $nextProductIds = array_slice($sortedCatProductIds, $currentProductCategoryIndex + 1, count($sortedCatProductIds)); //+1 for next product, -1 for previous product

    foreach ($nextProductIds as $productId) {
        $product = Mage::getModel('catalog/product')->load($productId);

        if ($product && $product->getId() && $product->isVisibleInCatalog() && $product->isVisibleInSiteVisibility()) {
            return $product->getProductUrl();
        }
    }

    return false;
}

Answer 4

There is an extension by aheadWorks I worked with in the past. It is not cheap, but does its job.

http://ecommerce.aheadworks.com/magento-extensions/user-experience/previous-next.html