Calling & Displaying Attachments from Sub-Pages - WordPress - php

Question

I'm new to WordPress (duh) and trying something I'm very close to getting.
I have several Sub-Pages, each of which has attachments - images. I simply want to display these images. The client will regularly be adding more subpages so the code has to know to only display the images of its self, so to speak. An issue I'm running into is each subpage is displaying all the attachments of all subpages.
In my Functions.php I have this code to determine if the page is infact a subpage:
//find out if it is a suppage to use in page.php as function 'is_subpage'
function is_subpage() {
global $post; // load details about this page
if ( is_page() && $post->post_parent ) { // test to see if the page has a parent
return $post->post_parent; // return the ID of the parent post
} else { // there is no parent so ...
return false; // ... the answer to the question is false
}
}
In my page.php I have an If statement, for all my usual pages. It culminates in this:
elseif ( is_subpage() ) {
get_template_part( 'exhibition-template' );
get_template_part( 'normalfooter' );
}
In exhibition-template.php, where I want my images to appear I have this:
<?php
if ( is_subpage( $post->ID ) ) { //I think I screwed up here, innermost brackets
$args = array(
'order' => 'ASC',
'post_type' => 'attachment',
'post_parent' => $post->ID, //or is my issue here...?
'post_mime_type' => 'image',
'post_status' => null,
'numberposts' => -1,
);
$attachments = get_posts($args);
if ($attachments) {
foreach ($attachments as $attachment) {
echo wp_get_attachment_link($attachment->ID, 'large', false, false);
}
}
}
?>
However, what happens is each and every subpage simply displays all the images across all subpages, and frankly, I'm just too DUMB to know how to progress, or what to play with, where to start.
Any ideas?

Answer 1

It looks like you have a few issues.
When testing to see if a page is a subpage you should test to see if $post->post_parent is greater than 0. So like this:
if ( is_page() && $post->post_parent > 0 ) {
return $post->post_parent;
} else {
return false;
}
You do not need to pass any arguments into if ( is_subpage( $post->ID ) )... You could also just use WordPress' get_attached_media() function to get these attachements as well. This is how your exhibition-template.php could look:
if ( is_subpage() ) {
$attachments = get_attached_media('image', $post->ID);
foreach ($attachments as $attachment) {
echo wp_get_attachment_link($attachment->ID, 'large', false, false);
}
}