Use attribute name in layered navigation css class

Question

In my layered navigation I want to be able to theme the content for each attribute differently. I have done this by creating my own version of app\design\frontend\base\default\template\catalog\layer\view.phtml and adding a class with the attribute name (which I can then target with css) by modifying this line from

<dd><?php echo $_filter->getHtml() ?></dd>

to

<dd class="<?php echo $this->__($_filter->attribute_model->attribute_code) ?>"><?php echo $_filter->getHtml() ?></dd>

This works fine but I noticed I was getting the following error in my log at this line:

ERR (3): Notice: Trying to get property of non-object in app/design/frontend/mytheme/default/template/catalog/layer/view.phtml on line 53

Fortunately, it's invisible on the front end and I'd like to eliminate it.

It dawned on me that this happens when the layered navigation is in a category tree and so there are no active attributes. I have tried to test if an attribute exists using the likes of is_object but nothing's worked and it's exhausted my admittedly limited PHP skills.

Can anyone suggest a way that works?

Answer 1

You should die(var_dump($_filter)) var to see what is inside. After that you will be able to use the property of the object you need to achieve what you want.

Answer 2

What that error is saying is $_filter is not an object at a certain time o.o so what I would do is see what $_filter is returning when that error hits. You can do this with an log (There should be a weird occurrence when the error).

Before you call echo $this->__($_filter... log $_filter with this Mage::log(var_dump($_filter)). If its not an object then you should get a string or a number or an empty var o.o.

Answer 3

I believe your is_object() approach is correct here, you most likely were just using it incorrectly.

My guess is you had something similar to this:

<?php if (is_object($_filter)): ?> ... <?php endif ?>

I would try revising it to this:

<?php if (is_object($_filter->attribute_model)): ?> ... <?php endif ?>

Answer 4

Thanks for your suggestions which helped me work out what I was doing wrong. Fundamentally it was my poor php. I now have the following which means the error no longer occurs.

 <dd<?php if (!is_null($_filter->attribute_model)) {echo ' class="' . $this->__($_filter->attribute_model->attribute_code) . '" ';} ?>><?php echo $_filter->getHtml() ?></dd>