Attachment field – how to output in template?

• herrfischer

• October 17, 2015 at 1:08 am

I have an attachment field named “Copyright”, i get the information e. g. in my ACF galleries with get_post_meta( $image['ID'], 'copyright', true ).

Now i want to display this information on the images that the user puts in to a normal WYSIWYG field. How can i do this? With a filter?

• Jonathan

• October 17, 2015 at 4:56 am

Hi @herrfischer

Perhaps you can use this: https://codex.wordpress.org/Function_Reference/wp_generate_attachment_metadata

• herrfischer

• October 17, 2015 at 8:48 am

Okay i will try that, but as far as I know now, after googling a lot, the only way is to put it in the caption field, because otherwise wordpress will not put html to the image. I found one (very old) plugin that does it this way.

• herrfischer

• October 18, 2015 at 9:22 pm

I thought there could be a ACF function or something. Now I did it with a normal custom field and put it to the caption. For this I had to disable the caption and made a custom caption:

// add copyright to caption function
//////////////////////////////////////////////////////////
// add custom field to image editor
add_filter("attachment_fields_to_edit", "add_image_copyright", 10, 2);
function add_image_copyright($form_fields, $post) {
	$form_fields["copyright"] = array(
		"label" => __("Copyright"),
		"input" => "text",
		"value" => get_post_meta($post->ID, "copyright", true),
		"helps" => __("(Das \"©\" Zeichen wird automatisch hinzugefügt)"),
	);
 	return $form_fields;
}
add_filter("attachment_fields_to_save", "save_image_copyright", 10 , 2);
function save_image_copyright($post, $attachment) {
	if (isset($attachment['copyright']))
		update_post_meta($post['ID'], 'copyright', $attachment['copyright']);
	return $post;
}

// caption function for regular caption and copyright field
// disable regular caption and build a custom one
add_filter( 'disable_captions', create_function('$a', 'return true;') );
function image_send_to_editor_2($html, $id, $caption, $title, $align, $url, $size, $alt) {

    $width = 'auto';

    if ( preg_match( '/width="([0-9]+)/', $html, $matches ) ) {
        $width = $matches[1] . 'px';
    }

	// Extract attachment $post->ID
	preg_match('/\d+/', $id, $att_id);
	if (is_numeric($att_id[0]) && $copyright = get_post_meta($att_id[0], 'copyright', true)) {
		$cright .= '<span class="caption-customfield">&copy;&nbsp;' . $copyright . '</span>';
	}

    $output = '[caption id="attachment_' . $id . '" align="align' . $align . '" width="' . $width . '"]';
    $output .= $html;
    $output .= $cright.'<span class="caption-regular">'.$caption.'</span>'.'[/caption]';

    return $output;
}

add_filter('image_send_to_editor', 'image_send_to_editor_2', 10, 8);

This is the output:

<div id="attachment_1312" style="width: 310px" class="wp-caption alignleft">

<img class="alignleft size-medium wp-image-1312" src="http://localhost:8888/mywebsite/wp-content/uploads/2015/09/download102-300x225.jpg" alt="download10" height="225" width="300">

<p class="wp-caption-text">
	<span class="caption-customfield">©&nbsp; Name of Photographer</span>
</p>

</div>

• herrfischer

• October 19, 2015 at 11:03 pm

I ended up using the regular caption field.

It is no problem to show the attachment custom field under article thumbnails or gallery images, but if you put this field to the regular caption of images used to put in the tinyMCE there are some drawbacks:

– you have to do “disable_captions” (and then generate your own …) – that deletes the regular caption field from the editor 🙁
– the ACF attachment meta field is not available in the image editor, you have to go the library and edit the image information there to add content to the ACF field

This is confusing I think. Now i added the regular caption to the gallery and the post thumbnails.

• Jonathan

• October 20, 2015 at 6:22 am

That’s some extensive work you’ve done. Thanks a lot for sharing your findings.

Sorry you couldn’t get it working to your satisfaction but as I’m sure you know this has more to do with WP cores restrictions than ACF 🙂

Best of luck in your project!

• herrfischer

• October 20, 2015 at 6:30 am

Oh I’m quite happy with the solution. Only drawback is that the customer has to type a “©” when he wants to put copyright information, but I think that shouldn’t be a big deal 😉 .

The code above is more like copy pasted from here and there, fiddling around and see what happens, but when i reach a point at which I know there is no better way than standard wordpress/ACF solutions I am mostly happy with that because I know it is the best possible solution, and … I learned a little, maybe it helps in other situations in future 😉