Alphabetical list/index for custom tags -> even if empty - Wordpress
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In wordpress (3.4) I created some code which returns an alphabetical list/index of custom tags and filters the custom posts in a grid layout. The tags are named as "tagdirectory". The custom post is named "directory".

This is the code:

    <?php $list = ''; 
    $tags = get_terms( 'tagdirectory' ); 
    echo '<ul id="portfolio-filter">'; 
    echo'<li><a href="#all" title="">All</a></li>';
    $groups = array();
    if( $tags && is_array( $tags ) ) {
    foreach( $tags as $tag ) {
    $first_letter = strtoupper( $tag->name[0] );
    $groups[ $first_letter ][] = $tag;}
    if( !empty( $groups ) ) {
    foreach( $groups as $letter => $tags ) {
    $list .= "\n\t" . '<h2>' . apply_filters( 'the_title', $letter ) .'</h2>';
    $list .= "\n\t" . '<ul>';
    foreach( $tags as $tag ) {
    $lower = strtolower($tag->name);
    $name = str_replace(' ', ' ', $tag->name);
    $naam = str_replace(' ', '-', $lower);
    $list .= "\n\t\t" . '<li><a href="#'.$naam.'">'.$name.'</a></li>';
    }}}}else $list .= "\n\t" . '<p>Sorry, but no tags were found</p>';print $list;
    echo "</ul>";
    ?>


This works perfectly but I would also like for empty letters from the alphabet to be shown.

For example, now it returns:

A

Aicher Otl

Apeloig Philippe

B

Bass Saul

F

Fitszimmons Maureen

... and so on

But it doesn't show the empty letter groups because there are no tags starting with this letter. I do need it to show the capital letter for empty groups though, like so:

A

Aicher Otl

Apeloig Philippe

B

Bass Saul

C

D

E

F

Fitszimmons Maureen

G

... and so on

Can anybody help me and tell me what code I should add for this to work?

Thanks!