get_children() returns ALL attachments instead only those attached to 'post_parent'

Question

I want to pull four random images from the current post's attachments to display as "featured images". Therefor I am using the following function:

function fs_gallery_featured_thumbs( $post_id ) { 
    // DEBUG: validate parent post ID
    echo $post_id;
    // Query to get images for this post
    $query = array(
        'post_parent'       => $post_id,
        'post_type'         => 'attachment',
        'post_mime_type'    => 'image',
        'order'             => 'RAND',
        'exclude'           => get_post_thumbnail_id( $post_id ) );

    $images = array_rand( get_children( $query ), 4);    
    // If images exist for this page
    if ( $images ) {
        echo '<div class="featured-thumbs">';
        $i = 1;
        foreach ( $images as $image ) {
            $imageAttributes = wp_get_attachment_image_src( $image, 'gallery-thumbnail-1x1' );
            echo '<a href="'.get_permalink().'" class="featured-thumb-link featured-thumb-link-'.$i.'"><img src="'.$imageAttributes[0].'" alt="'.the_title_attribute(array('echo'=>0)).'" class="featured-thumb featured-thumb-'.$i++.'" width="152px" height="152px" /></a>';
        }
        echo '</div>';
    }
}

The only parameter is passed from inside the loop via the_ID() and is in fact returning the correct parent post ID (I verified this using echo $post_id; inside above function.

However, for some reason, the array images contains four random items of ALL images that are inside the media gallery, not only the ones which are attached to the current post.

How can I really only get the images which are attached to the post? When I use the [gallery] shortcode in this post, the correct images are shown. All I want is four random images from that gallery.

Any ideas?

Not sure if this has anything to do with it: the posts which all the other (wrong) images were attached to, were deleted at some point. The images still linger inside the media gallery however, however the post ID of the post they are "used in" (not sure about the correct English term here, my WP is German) is different to my post_parent.

Thx.

Answer 1

hat I do: in my template that I use to display posts within the standard loop, I make a call to above function: fs_gallery_featured_thumbs( $post->ID ) (originally I used the_ID() instead of $post->ID which gave me trouble. I guess bescause the_ID() actually echoes the ID, rihgt?).

Exactly. The problem isn't in your function itself, but rather in the parameter you pass to it. Because the_ID echoes rather than returns its value, the actual function was getting passed NULL, resulting in attachments for all posts being queried.

Solution:

• Pass $post->ID (in a context where $post is globalized)
• Pass get_the_ID() (inside the Loop)