After update, the field ACF not appear in page

I have the same probleme.
I try : $a_z_query->the_post_thumbnail();

But it doesn’t work.

Math.

• This reply was modified 6 years, 2 months ago by mathskater.

This is a side-effect of my attempting to save a bit of memory and generation time. I purposely don’t load the full post object, so the thumbnail isn’t in memory.

Try with the following instead:

<?php
$post = $a_z_query->get_the_item_object( 'I understand the issues!' );
if ( has_post_thumbnail( $post->ID ) ) :
    the_post_thumbnail( 'thumbnail' );
endif;
?>

The text I understand the issues! must be exactly that, to confirm that you do understand that on a large collection of posts you might hit slowness or memory usage problems.

Sorry, but for me it does not work.

same problem

What is the behaviour of the failure?

e.g. Does the page show an error? Is the page completely loaded, or is the html cut-off? Is the listing complete, just missing the thumbnails? Do any thumbnails load or are they all missing?

Could you try some debugging steps such as inserting an else clause on the has_thumbnail() check – the example below will print the post ID to make sure that the $post object is loaded properly:

if ( has_thumbnail( $post->ID ) ) :
    ...
else :
    echo "<br />The thumbnail cannot be found. The post ID is '{$post->ID}'.<br />";
endif;

Here is the error that appears :

Fatal error: Uncaught Error: Call to undefined function has_thumbnail() in /app/public/wp-content/themes
Stack trace:
#0 /app/public/wp-content/plugins/a-z-listing/classes/class-a-z-listing.php(654): include()
#1 /app/public/wp-content/plugins/a-z-listing/classes/class-a-z-listing.php(675): A_Z_Listing->do_template('/app/public/wp-...')
#2 /app/public/wp-content/plugins/a-z-listing/classes/class-a-z-listing.php(690): A_Z_Listing->the_listing()
#3 /app/public/wp-content/plugins/a-z-listing/functions/shortcode.php(203): A_Z_Listing->get_the_listing()
#4 /app/public/wp-includes/shortcodes.php(319): a_z_shortcode_handler(Array, '', 'a-z-listing')
#5 [internal function]: do_shortcode_tag(Array)
#6 /app/public/wp-includes/shortcodes.php(197): preg_replace_callback('/\\[(\\[?)(a\\-z\\-...', 'do_shortcode_ta...', '[a-z-listing po...')
#7 /app/public/wp-includes/class-wp-hook.php(286): do_shortcode('[a-z-listing po...')
#8 /app/public/wp-includes/plugin.php(203): WP_Hook->apply_filters('[a-z-li in /app/public/wp-content/themes on line 51

I mistyped, and you copied verbatim.

Try replacing has_thumbnail with has_post_thumbnail to get past that specific undefined function error.

Thank’s !
But nothing is displayed, that’s the code I’m using, maybe it can help to understand where the problem is coming from.

<ul class="columns max-<?php echo $column_limit; ?>-columns">
<?php
while ( $a_z_query->have_items() ) :
$a_z_query->the_item();
?>
<li>
<a href="<?php $a_z_query->the_permalink(); ?>">
<?php
$post = $a_z_query->get_the_item_object( 'I understand the issues!' );										if ( has_post_thumbnail( $post->ID ) ) :										    the_post_thumbnail( 'featured-image-abecedaire' );										endif;
?>
<div class="az-box-data">										<div class="glass"><i class="fal fa-search-plus"></i></div>									</div>
<div class="az-title"><?php $a_z_query->the_title(); ?></div>
</a>
</li>
<?php endwhile; ?>
</ul>

The code you shared in the previous post does not call the_post_thumbnail or get_the_post_thumbnail, nor does it check that there is a thumbnail with has_post_thumbnail. You still need to do those bits. They need to appear after this line:

$post = $a_z_query->get_the_item_object( 'I understand the issues!' );