How to Output Codestar Framework Group Field Values

A group field in a Codestar Framework metabox lets editors add as many sets of sub-fields as they need with a button, for example one row per car model and year. The framework saves the group inside the metabox’s post meta array, as a list of entries, each an array keyed by sub-field id. To output it, load the metabox with get_post_meta(), take the group by its id and loop through the entries.

The code below is for Codestar Framework 2, the current version, where metaboxes need the premium version. A short section at the end covers sites that still run 1.x. Reading a single Codestar metabox field explains how the framework stores metabox data and where the project stands today: the latest release, 2.3.1, is from January 2024.

Step 1: define the group field

Register the metabox with CSF::createMetabox() and add the group to one of its sections with CSF::createSection(), in your theme’s functions.php or the plugin that loads the framework:

if ( class_exists( 'CSF' ) ) {

    CSF::createMetabox( 'mbhouse_project_meta', array(
        'title'     => 'Project Details',
        'post_type' => 'post',
    ) );

    CSF::createSection( 'mbhouse_project_meta', array(
        'title'  => 'Availability',
        'fields' => array(
            array(
                'id'           => 'car_year_lists_x',
                'type'         => 'group',
                'title'        => 'Year Data',
                'desc'         => 'Add availability for cars',
                'button_title' => 'Add New Year',
                'fields'       => array(
                    array(
                        'id'    => 'mb_car_year_details_av',
                        'type'  => 'text',
                        'title' => 'Car Model & Year',
                    ),
                ),
            ),
        ),
    ) );
}

• mbhouse_project_meta is the metabox id. All the metabox’s fields are saved together in one post meta entry under that key. Set post_type to the post type that needs the box.
• car_year_lists_x is the group’s id, the key you’ll use to read the group later.
• button_title is the label of the button that adds a new entry.
• The inner fields array defines the sub-fields of each entry; here a single text field with the id mb_car_year_details_av. Add more sub-fields the same way.

Step 2: output the group values

In the template that displays the post, inside the Loop, load the metabox data and loop through the entries:

<?php
$meta_data   = get_post_meta( get_the_ID(), 'mbhouse_project_meta', true );
$meta_groups = ! empty( $meta_data['car_year_lists_x'] ) ? $meta_data['car_year_lists_x'] : array();
?>

<?php if ( $meta_groups ) : ?>
    <ul class="car-years">
        <?php foreach ( $meta_groups as $meta_group ) : ?>
            <li><?php echo esc_html( $meta_group['mb_car_year_details_av'] ?? '' ); ?></li>
        <?php endforeach; ?>
    </ul>
<?php endif; ?>

• get_post_meta() with true returns the metabox array, and $meta_data['car_year_lists_x'] is the group inside it.
• The ternary line stores the entries in $meta_groups, or an empty array if nothing has been saved, and the if skips the list in that case. The ! empty() check also matters on PHP 8: for a post without saved data, get_post_meta() returns an empty string, and reading a key from a string is a fatal error.
• Each $meta_group is one entry: an array keyed by sub-field id, so $meta_group['mb_car_year_details_av'] holds that entry’s text. The ?? '' prints nothing, instead of a warning, for an entry without that value.
• esc_html() escapes each value. Change the list markup to whatever your design needs.
• get_the_ID() needs the Loop. Outside it, use the ID of the post you want, or $post->ID with the global $post.

What does the saved group data look like?

While you build the template, print_r( $meta_data ) shows the structure. With two entries, the metabox above returns:

Array
(
    [car_year_lists_x] => Array
        (
            [0] => Array
                (
                    [mb_car_year_details_av] => Toyota Corolla 2021
                )

            [1] => Array
                (
                    [mb_car_year_details_av] => Honda Civic 2023
                )

        )

)

If the metabox is created with 'data_type' => 'unserialize', every field is saved under its own id instead, and get_post_meta( get_the_ID(), 'car_year_lists_x', true ) returns the list of entries directly.

Codestar Framework 1.x (metabox.config.php)

On a 1.x site, the group goes in the fields array of a metabox section in the framework’s config/metabox.config.php file:

$options[] = array(
  'id'        => 'mbhouse_project_meta',
  'title'     => 'Project Details',
  'post_type' => 'post',
  'context'   => 'normal',
  'priority'  => 'default',
  'sections'  => array(
    array(
      'name'   => 'availability',
      'title'  => 'Availability',
      'fields' => array(

        array(
          'id'           => 'car_year_lists_x',
          'type'         => 'group',
          'title'        => 'Year Data',
          'desc'         => 'Add availability for cars',
          'button_title' => 'Add New Year',
          'fields'       => array(
            array(
              'id'    => 'mb_car_year_details_av',
              'type'  => 'text',
              'title' => 'Car Model & Year',
            ),
          ),
        ),

      ),
    ),
  ),
);

CSFramework_Metabox::instance( $options );

Version 1.x stores the group the same way, as a list of entries under the group id inside the metabox array, so the template code from Step 2 outputs 1.x data unchanged.