I need to be able to: 1.) assign categories to images and 2.) add classes to all images that correspond to their assigned categories.
I was able to add categories to images with the following:
function ug_add_categories_to_attachments() {
register_taxonomy_for_object_type( 'category', 'attachment' );
}
add_action( 'init' , 'ug_add_categories_to_attachments' );
And I found a function to add a class to images as so:
function add_image_class($class){
$class .= ' additional-class';
return $class;
}
add_filter('get_image_tag_class','add_image_class');
But I’m not advanced enough with php to take it much further. I tried this
function ug_add_image_class($class){
foreach(get_the_category() as $cat) { $class .= ' category-'.$cat->slug; };
return $class;
}
add_filter('get_image_tag_class','ug_add_image_class');
but no love…
Help? Ideas? Please? and Happy Friday!
1 Answer
This should hopefully do the trick:
/**
* Append the image categories to the current image class.
*
* @see http://wordpress.stackexchange.com/a/156576/26350
*/
add_filter( 'get_image_tag_class',
function( $class, $id, $align, $size )
{
foreach( (array) get_the_category( $id ) as $cat )
{
$class .= ' category-' . $cat->slug;
}
return $class;
}
, 10, 4 );
Testing (WP 3.9.1):
If we set the image categories as (for example):
rolling-stones, steel-wheels-tour, wembley
Screenshot:
and then insert the image into the post, we get the extra classes as expected:
category-rolling-stones category-steel-wheels-tour category-wembley
Screenshot: