Recently I needed to recreate a specific gallery format in WordPress.
There are probably better ways to go about it, such as custom post types, but I needed something quick and easy.
The main gallery page needed to have a list of “categories” that were represented by images.
I used a WordPress Page that consisted of:
[gallery size="full" link="custom_url"]
Each “category” was an image that linked to a WordPress Page.
On the category pages, for each gallery item, there needed to be a caption on top of the image, the image with no link, and a description under the image.
For each of these WordPress pages I used:
[gallery size="full" link="none"]
To create this, I merged the code from these two sources, moved the image caption tag to a different location, and added the image description in functions.php.
Sources:
The code below goes in functions.php in your theme directory.
<?php
/* -------------------------------
CUSTOM LINK PER GALLERY IMAGE
------------------------------- */
function rt_image_attachment_fields_to_edit( $form_fields, $post ) {
$form_fields["rt-image-link"] = array( "label" => __( "Custom Link" ),
"input" => "text", // default
"value" => get_post_meta($post->ID, "_rt-image-link", true ), //"helps" => __("To be used with special slider added via [rt_carousel] shortcode."),
);
return $form_fields;
}
add_filter( "attachment_fields_to_edit", "rt_image_attachment_fields_to_edit", null, 2 );
function rt_image_attachment_fields_to_save( $post, $attachment ) {
// $attachment part of the form $_POST ($_POST[attachments][postID])
// $post['post_type'] == 'attachment'
if ( isset( $attachment['rt-image-link'] ) ) {
// update_post_meta(postID, meta_key, meta_value);
update_post_meta( $post['ID'], '_rt-image-link', $attachment['rt-image-link'] );
}
return $post;
}
add_filter( "attachment_fields_to_save", "rt_image_attachment_fields_to_save", null, 2 );
/* -------------------------------
MODIFIED CORE FUNCTION
------------------------------- */
add_shortcode( 'gallery', 'geekee_gallery_shortcode' );
/**
* The Gallery shortcode.
*
* This implements the functionality of the Gallery Shortcode for displaying
* WordPress images on a post.
*
* @since 2.5.0
*
* @param array $attr Attributes attributed to the shortcode.
* @return string HTML content to display gallery.
*/
function geekee_gallery_shortcode( $attr ) {
global $post, $wp_locale;
static $instance = 0;
$instance++;
// Allow plugins/themes to override the default gallery template.
$output = apply_filters( 'post_gallery', '', $attr );
if ( $output != '' ) return $output;
// We're trusting author input, so let's at least make sure it looks like a valid orderby statement
if ( isset( $attr['orderby'] ) ) {
$attr['orderby'] = sanitize_sql_orderby( $attr['orderby'] );
if ( !$attr['orderby'] ) unset( $attr['orderby'] );
}
extract( shortcode_atts( array( 'order' => 'ASC',
'orderby' => 'menu_order ID',
'id' => $post->ID,
'itemtag' => 'dl',
'icontag' => 'dt',
'captiontag' => 'dd',
'columns' => 3,
'size' => 'thumbnail',
'include' => '',
'exclude' => '' ), $attr ) );
$id = intval( $id );
if ( 'RAND' == $order ) $orderby = 'none';
if ( !empty( $include ) ) {
$include = preg_replace( '/[^0-9,]+/', '', $include );
$_attachments = get_posts( array( 'include' => $include,
'post_status' => 'inherit',
'post_type' => 'attachment',
'post_mime_type' => 'image',
'order' => $order,
'orderby' => $orderby ) );
$attachments = array();
foreach ( $_attachments as $key => $val ) {
$attachments[$val->ID] = $_attachments[$key];
}
} elseif ( !empty( $exclude ) ) {
$exclude = preg_replace( '/[^0-9,]+/', '', $exclude );
$attachments = get_children( array( 'post_parent' => $id,
'exclude' => $exclude,
'post_status' => 'inherit',
'post_type' => 'attachment',
'post_mime_type' => 'image',
'order' => $order,
'orderby' => $orderby ) );
} else {
$attachments = get_children( array( 'post_parent' => $id,
'post_status' => 'inherit',
'post_type' => 'attachment',
'post_mime_type' => 'image',
'order' => $order,
'orderby' => $orderby ) );
}
if ( empty( $attachments ) ) return '';
if ( is_feed() ) {
$output = "\n";
foreach ( $attachments as $att_id => $attachment ) $output .= wp_get_attachment_link( $att_id, $size, true ) . "\n";
return $output;
}
$itemtag = tag_escape( $itemtag );
$captiontag = tag_escape( $captiontag );
$columns = intval( $columns );
$itemwidth = $columns > 0 ? floor( 100 / $columns ) : 100;
$float = is_rtl() ? 'right' : 'left';
$selector = "gallery-{$instance}";
$gallery_style = $gallery_div = '';
if ( apply_filters( 'use_default_gallery_style', true ) ) $gallery_style = "
<style type='text/css'>
#{$selector} {
margin: auto;
}
#{$selector} .gallery-item {
float: {$float};
margin-top: 10px;
text-align: center;
width: {$itemwidth}%;
}
#{$selector} img {
border: 2px solid #cfcfcf;
}
#{$selector} .gallery-caption {
margin-left: 0;
}
</style>
<!-- see gallery_shortcode() in wp-includes/media.php -->";
$size_class = sanitize_html_class( $size );
$gallery_div = "<div id='$selector' class='gallery galleryid-{$id} gallery-columns-{$columns} gallery-size-{$size_class}'>";
$output = apply_filters( 'gallery_style', $gallery_style . "\n\t\t" . $gallery_div );
$i = 0;
foreach ( $attachments as $id => $attachment ) {
if ( isset( $attr['link'] ) && 'file' == $attr['link'] ) {
$link = wp_get_attachment_link( $id, $size, false, false );
} elseif ( isset( $attr['link'] ) && 'none' == $attr['link'] ) {
$link = wp_get_attachment_image( $id, $size, false );
} else {
$link = wp_get_attachment_link( $id, $size, true, false );
}
/* -------------------------------
MODIFICATION ################
------------------------------- */
$image = wp_get_attachment_image( $id, $size, false );
$attachment_meta = get_post_meta( $id, '_rt-image-link', true );
if ( $attachment_meta ) {
if ( $attr['link'] == 'custom_url' ) {
$link = $attachment_meta;
}
}
$output .= "<{$itemtag} class='gallery-item'>";
if ( $captiontag && trim( $attachment->post_excerpt ) ) {
$output .= "<{$captiontag} class='gallery-caption'>" . wptexturize( $attachment->post_excerpt ) . "</{$captiontag}>";
}
$output .= "<{$icontag} class='gallery-icon'>";
/* -------------------------------
MODIFICATION ################
------------------------------- */
if ( $attachment_meta ) {
$output .= "<a href='$link'>$image</a>";
} else {
$output .= $link;
}
if ( trim( $attachment->post_content ) ) {
$output .= '<br />'.wptexturize( $attachment->post_content );
}
$output .= "</{$icontag}>";
$output .= "</{$itemtag}>";
if ( $columns > 0 && ++$i % $columns == 0 ) $output .= '<br style="clear: both;" />';
}
$output .= "<br style='clear: both;' /></div>\n";
return $output;
}
?>

