Hi @inhouse
You got the “Undefined index” error because the $images variable consists the gallery arrays now, not the image arrays. You need to loop the galleries first and then loop the images.
Another approach would be using array_merge() function like this:
$images = array();
foreach( $pages as $page ) { ?>
<?php $images = array_merge($images, get_field('slideshow_images', $page->ID));
}
This page should give you more idea about it: http://php.net/manual/en/function.array-merge.php.
I hope this makes sense.
