category_css_class │ filter-hook │ WP 4.2.0

Filters the list of CSS classes to include with each category in the list.

Usage

add_filter( 'category_css_class', 'wp_kama_category_css_class_filter', 10, 4 );

/**
 * Function for `category_css_class` filter-hook.
 * 
 * @param string[] $css_classes An array of CSS classes to be applied to each list item.
 * @param WP_Term  $category    Category data object.
 * @param int      $depth       Depth of page, used for padding.
 * @param array    $args        An array of wp_list_categories() arguments.
 *
 * @return string[]
 */
function wp_kama_category_css_class_filter( $css_classes, $category, $depth, $args ){

	// filter...
	return $css_classes;
}

$css_classes(string[])

An array of CSS classes to be applied to each list item.

$category(WP_Term)

Category data object.

$depth(int)

Depth of page, used for padding.

$args(array)

An array of wp_list_categories() arguments.

Changelog

Where the hook is called

$css_classes = implode( ' ', apply_filters( 'category_css_class', $css_classes, $category, $depth, $args ) );

Where the hook is used in WordPress