Wordpress Genesis custom taxonomy archive shows 3 repeats of each post

Question

I am using a child theme on genesis. I have set up a custom post type and a custom taxonomy, and I'm using Advanced Custom Fields to put a gallery on each page of the CPT. On the taxonomy archive pages, I would like to show a single image from each gallery as a thumbnail, linking to the post. I have successfully set this up using a new template for the custom taxonomy, but if I set 'numberposts' => -1 to show all the posts, I get eight repeats of each post/thumbnail. If I set it to 'numberposts' => 1, I get 3 repeats of each post/thumbnail. How do I show just a single thumbnail from each post?

I don't know for sure that this is a wordpress problem, but I think it must be something to do with how I am setting up the custom loop?

<?php
//* Template Name: Press Release; Archive

remove_action ('genesis_loop', 'genesis_do_loop'); // Remove the standard loop 
add_action ('genesis_after_loop', 'collection_categories'); // add custom loop
function collection_categories(){

$terms = get_terms('collection_categories');
foreach($terms as $term) {
$posts = get_posts(array(
        'post_type' => 'collections',
        'tax_query' => array(
            array(
                'taxonomy' => 'collection_categories',
                'field' => 'slug',
                'terms' => $term->slug
            )
        ),
        'numberposts' => 1
    ));

foreach($posts as $post) {

//* One image from gallery on archive pages

        if ( have_posts() ) : 
while ( have_posts() ) : the_post();

    $images = get_field('gallery'); 
    $image_1 = $images[0];
    $link = get_the_permalink();

?>

<a href="<?php echo $link ?>"><img src="<?php echo $image_1['sizes']    ['thumbnail']; ?>" alt="<?php echo $image_1['alt']; ?>" /></a>
<?php

        endwhile;
        endif;
}
}
}
genesis();

Answer 1

You are using a nested loop in your code. You should only use the foreach loop, and pass the post ID to get_field(). Here's an example:

$terms = get_terms( 
    [ 
        'taxonomy' => 'collection_categories', 
        'orderby'  => 'name', 
        'order'    => 'DESC'
    ] 
);

// Rest of the code  here 

foreach ( $posts as $post ) {

    //* One image from gallery on archive pages
    $images  = get_field( 'gallery', $post->ID ); 
    $image_1 = $images[0];

    ?>

    <a href="<?php the_permalink( $post->ID ); ?>">
        <img src="<?php echo $image_1['sizes']['thumbnail']; ?>" alt="<?php echo $image_1['alt']; ?>" />
    </a><?php

}

// Don't forget to reset the postdata
wp_reset_postdata();