Check if page is filterable

Question

I'm building a store responsively and for the top navigation on a mobile I have an option to "filter" which should only be shown on pages which are filterable, such as the search results page, the catalog pages.

This is just a link with an id which makes a siderbar slide in/out. But the link only needs to be shown if there's actually something to filter.

I've tried looking in to the Catalog_Block_Layer class and there are a couple of methods which I thought might work, but don't. Such as:

Mage::getSingleton('Mage_Catalog_Block_Layer')->canShowBlock()

and

Mage::getSingleton('Mage_Catalog_Block_Layer')->canShowOptions()

Any ideas how I can achieve this?

Answer 1

The methods in your question are not working because by the time you call them Mage_Catalog_Block_Layer might be not yet instantiated.

One dirty solution can be the following:

if (count(array_intersect($this->getLayout()->getUpdate()->getHandles(), array('catalog_category_layered', 'catalogsearch_result_index'))) {
    ...
}