For $vars['id'] == 1 render field Y instead of field X

Question

So on my Blog listing page, the first listing is "featured" meaning it spans two columns rather than one, I've achieved most of my styling changes by adding CSS class feature to $vars['id'] == 1 for the blog page.

However, the image for first teaser is a different proportions and therefore uses custom field header image rather than custom field thumbnail image. In the following:

function innovista_preprocess_node(&$vars) {
  if ($vars['id'] == 1 && arg(0) == 'blog') {
    $vars['classes_array'][] = 'feature';

    //do stuff to switch field here?

  }
}

I want to add a command to switch render of $content['field_blog_thumbnail_image'] with render of $content['field_blog_header_image']. How can I go about this?

Thanks for your time!

Answer 1

Ok so the way I achieved this was to go into my node--content_type.tpl.php file and do a simple check for 'feature' in the classes string. Printing the correct image depending on the outcome of the check.

So first in admin I set both header and thumbnail images to display when showing as a teaser. But then in the template file I began by hiding them:

hide($content['field_blog_thumbnail_image']);
hide($content['field_blog_header_image']);

This means that they don't render with print render($content);

In the place where I wanted to display the image I then used simple logic to check the $classes variable to see if the string contained 'feature'. If it did I render the header image, if not, the thumbnail image:

if(strpos($classes,'feature')==true){
    print render($content['field_blog_header_image']);
} else{
    print render($content['field_blog_thumbnail_image']);
}