Lightbox Group for custom hook

I have this custom hook for WordPress Galleries:

function custom_gallery_output( $output, $atts, $instance ) {
global $post;

// Get the gallery image IDs
if ( isset( $atts['ids'] ) ) {
    $ids = explode( ',', $atts['ids'] );
} else {
    $ids = [];
}

if ( empty( $ids ) ) {
    return $output;
}

$gallery_id = 'gallery-' . $post->ID;

$output = '<div class="custom-gallery">';

foreach ( $ids as $id ) {
    $image_url = wp_get_attachment_image_url( $id, 'full' );

    $output .= '<figure class="gallery-item">';
    $output .= '<div class="gallery-icon landscape">';
    $output .= '<a href="' . esc_url( $image_url ) . '" class="gallery" data-lightbox="gallery" style="display:block; background-image:url(' . esc_url( $image_url ) . '); background-size:cover; background-position:center; width:100%; height:300px;"></a>';
    $output .= '</div></figure>';
}

$output .= '</div>';

return $output;

}
add_filter( ‘post_gallery’, ‘custom_gallery_output’, 10, 3 );

This works, except it only shows one image, I am trying to create a set via data-lightbox=”gallery” but that did not work. It opens the image I click on in lightbox, but I have to close it and open the next image, Dont know why the arrows dont appear.

• This topic was modified 1 week, 6 days ago by jamessuske1985.