<?php
/*
* Tests if any of a post's assigned categories are descendants of target categories
*
* @param int|array $cats The target categories. Integer ID or array of integer IDs
* @param int|object $_post The post. Omit to test the current post in the Loop or main query
* @return bool True if at least 1 of the post's categories is a descendant of any of the target categories
* @see get_term_by() You can get a category by name or slug, then pass ID to this function
* @uses get_term_children() Passes $cats
* @uses in_category() Passes $_post (can be empty)
* @version 2.7
* @link http://codex.wordpress.org/Function_Reference/in_category#Testing_if_a_post_is_in_a_descendant_category
*/
if ( ! function_exists( 'post_is_in_descendant_category' ) ) {
function post_is_in_descendant_category( $cats, $_post = null ) {
foreach ( (array) $cats as $cat ) {
// get_term_children() accepts integer ID only
$descendants = get_term_children( (int) $cat, 'category' );
if ( $descendants && in_category( $descendants, $_post ) )
return true;
}
return false;
}
}
function graphene_custom_header_image( $image ){
if ( in_category(52) || post_is_in_descendant_category(52) ){
/* The script to rotate through possible images here. */
// Get the current category
if ( $cat = get_query_var( 'cat' ) ){
$cat = get_the_terms( $cat, 'category' );
$cat = $cat[1]->slug;
} else {
global $post;
$cat = get_the_category( $post->ID );
$cat = $cat[0]->slug;
}
// The directory where the images reside
$dir = get_stylesheet_directory() . '/images/custom-headers/' . $cat;
if ( is_dir( $dir ) ){
// Get all images from the $dir above
$images = glob( $dir . "/*.jpg" );
if ( $images ){
// Pick a random image
$key = array_rand( $images );
// Make sure the resulting image is assigned to the $image variable
$image = get_stylesheet_directory_uri() . "/images/custom-headers/$cat/" . basename( $images[$key] );
}
}
}
return $image;
}
add_filter( 'graphene_header_image', 'graphene_custom_header_image' );
?>