Cross-references?

Thank you – that’s ingenious! I’m afraid I don’t quite see how it would work, though. Presumably my custom taxonomy, subjects, would have to have a custom field called aliases which if the term is a X-ref would contain a list of comma-separated alias subjects. That’s okay, I think.

The problem is that each of those aliases would have to actually function in the same way as it does in its proper place in the list – it would have to link to all the posts that had the alias subject. Wouldn’t you have to use another loop, to find those posts? That could be very resource-hungry.

To use my previous example, an entry might look like this:
Thrush see Turdus turdus; garden birds.

If only it were possible to include two taxonomies in one listing! Then I could combine the subject taxonomy with an alias taxonomy. The alias taxonomy wouldn’t have any posts, it would simply have the entire cross-reference as its title (unlinked – the user would have to find the item referred to manually, as with a book index).

• This reply was modified 3 years, 9 months ago by pcgardner.

But the documentation says:

taxonomy: sets the taxonomy containing the terms specified in the terms=”” option
Default value: unset.
May only contain one value.
Must be the slug of the taxonomy.

Presumably the documentation is out of date. If I’d known that I could have saved myself quite a bit of time!

Anyway, thank you very much for your help. I’ll experiment with the code along the lines you suggest.

Thanks to your help I now have a fully working index with cross-references incorporated, and thought I would share my customized template in case anyone else wants to do something similar.

I set up two custom taxonomies (using PODS, but that shouldn’t make any difference). The first is ‘subject’, which has no custom fields and works like categories or tags. The second is ‘cross_reference’, with one custom field called ‘target_subjects’. For example, a cross-reference with the title ‘dunnock’ might have ‘garden birds’ in its target_subjects field.

Here is my a-z-listing.php template file; it is in the root of my theme folder. The customized section is indicated by comments.

<?php
/**
 * Default multicolumn template for the A-Z Listing plugin
 *
 * This template will be given the variable <code>$a_z_query</code> which is an instance
 * of <code>A_Z_Listing</code>.
 *
 * You can override this template by copying this file into your theme
 * directory.
 *
 * @package a-z-listing
 */

/**
 * This value indicates the number of posts to require before a second column
 * is created. However, due to the design of web browsers, the posts will flow
 * evenly between the available columns. E.g. if you have 11 items, a value of
 * 10 here will create two columns with 6 items in the first column and 5 items
 * in the second column.
 */
$_a_z_listing_minpercol = 10;
?>
<div id="az-tabs">
	<div id="letters">
		<div class="az-letters">
			<?php $a_z_query->the_letters(); ?>
		</div>
	</div>
	<?php if ( $a_z_query->have_letters() ) : ?>
	<div id="az-slider">
		<div id="inner-slider">
			<?php
			while ( $a_z_query->have_letters() ) :
				$a_z_query->the_letter();
				?>
				<?php if ( $a_z_query->have_items() ) : ?>
					<?php
					$item_count  = $a_z_query->get_the_letter_count();
					$num_columns = ceil(
						$item_count / $_a_z_listing_minpercol
					);
					?>
					<div class="letter-section"
						id="<?php $a_z_query->the_letter_id(); ?>">
						<h2 class="letter-title">
							<span>
								<?php $a_z_query->the_letter_title(); ?>
							</span>
						</h2>
						<?php $column_class = "max-$num_columns-columns"; ?>
						<ul class="columns <?php echo $column_class; ?>">
							<?php
							while ( $a_z_query->have_items() ) :
								$a_z_query->the_item();
								?>
								<li>
/** CUSTOMIZED CODE BEGINS */
								<?php 
								$term = $a_z_query->get_the_item_object( 'I understand the issues!' ); 
								if ( 'cross_reference' === $term->taxonomy ) : ?>
								<?php $a_z_query->the_title(); ?>:<em> see </em>
								<?php echo get_term_meta( $term->term_id, '', false )["target_subjects"][0] ; ?>
								<?php else : ?>
									<a href="<?php $a_z_query->the_permalink(); ?>">
										<?php $a_z_query->the_title(); ?>
									</a>
								<?php endif ?>
/** CUSTOMIZED CODE ENDS */
								</li>
							<?php endwhile; ?>
						</ul>
						<div class="back-to-top">
							<a href="#letters">
								<?php _e( 'Back to top', 'a-z-listing' ); ?>
							</a>
						</div>
					</div>
					<?php
				endif;
			endwhile;
			?>
		</div>
	</div>
</div>
<?php else : ?>
	<p>
		<?php
		esc_html_e(
			'There are no posts included in this index.',
			'a-z-listing'
		);
		?>
	</p>
	<?php
endif;

• This reply was modified 3 years, 8 months ago by pcgardner. Reason: Improved accuracy