Trouble getting file url of file attachment in cloneable group

I did a test with the code using the file attachment only not in a group like this and it works fine:

add_action( 'woocommerce_after_add_to_cart_button', 'product_download_button_test', 5 );
function product_download_button_test() { ?>
    <div class="dropdown">
        <button class="product-downloads-button nectar-button large regular accent-color regular-button" onclick="return false;">DOWNLOADS
            <i class="fa fa-caret-down"></i>
        </button>
        <div class="dropdown-content"> <?php
            $file_attachments = rwmb_meta( 'attachment_test' );
            if ( ! empty( $file_attachments ) ) {
                foreach ( $file_attachments as $file_attachment ) { 
                    if ( isset( $file_attachment ) ) {
                        $file_url = ( $file_attachment['url'] ); ?>
                        <a href="<?php echo $file_url; ?>" target="_blank"><?php echo $file_attachment['name']; ?> </a>
                    <?php } 
                }
            } ?> 
        </div>
    </div>    
<?php }

But when it seems as soon as the file attachment is in a group, I can return any info from it. This is the same only with the file attachment in a group:

add_action( 'woocommerce_after_add_to_cart_button', 'product_download_button_test', 5 );
function product_download_button_test() { ?>
    <div class="dropdown">
        <button class="product-downloads-button nectar-button large regular accent-color regular-button" onclick="return false;">DOWNLOADS
            <i class="fa fa-caret-down"></i>
        </button>
        <div class="dropdown-content"> <?php
            $file_attachments = rwmb_meta( 'attachment_test' );
            if ( ! empty( $file_attachments ) ) {
                foreach ( $file_attachments as $file_attachment ) { 
                    if ( isset( $file_attachment ) ) {
                        $file_url = ( $file_attachment['url'] ); ?>
                        <a href="<?php echo $file_url; ?>" target="_blank"><?php echo $file_attachment['name']; ?> </a>
                    <?php } 
                }
            } ?> 
        </div>
    </div>    
<?php }

I get an error "undefined index url" and when I try to use wp_get_attachment_url() or get_attached_file() it returns nothing.
It seems like whatever I try to do to get info from $file_attachment['attachment'], or when a file attachment is in a group, it is always empty.

Hi Anh,

Just following up on this. When using the code you helped fix here:

add_action( 'woocommerce_after_add_to_cart_button', 'product_download_button', 5 );
function product_download_button() { 
    $file_attachments = rwmb_meta( 'file_attachments' );
    if ( ! empty( $file_attachments ) ) { ?>
        <div class="dropdown">
            <button class="product-downloads-button nectar-button large regular accent-color regular-button" onclick="return false;">DOWNLOADS
                <i class="fa fa-caret-down"></i>
            </button>
            <div class="dropdown-content"> <?php
            foreach ( $file_attachments as $file_attachment ) {
                $file_name = isset( $file_attachment['file_name'] ) ? $file_attachment['file_name'] : '';
                    if ( isset( $file_attachment['attachment'] ) ) {
                        $file_id = reset( $file_attachment['attachment'] ); // Get the first file only.
                        $file_url = wp_get_attachment_url( $file_id ); 
                        echo '<a href="' . $file_url . '" target="_blank">' . $file_name . '</a>';
                    }
                }
            } ?>
        </div>
    </div>
<?php }

Even if there is no name or attachment for the file, the download button still shows on the product page even though there is nothing in it. I made another similar custom group field with a text and color picker and when I use this:

$special_colours = rwmb_meta( 'special_colours' );
    if ( ! empty( $special_colours ) ) {

When there is nothing in the fields for the product nothing displays, as it should correctly. Is this maybe because as you mentioned previously that the file_advanced is array and so if ( ! empty( $file_attachments ) ) { still sees that the attachment item in the group is not empty? Is there a way around this so that the download button is not displayed if there is nothing in the fields for that product?

Hi Long,

Thanks for the reply I gave that a shot and unfortunately it didn't work. I also took a look at some products and it looks like some are showing the special colour content while others are not even when there is no name or colour selected. Here is the colour code for reference:

add_filter( 'rwmb_meta_boxes', 'prefix_register_special_colours' );
function prefix_register_special_colours( $meta_boxes ) {
    $meta_boxes[] = array(
        'id' => 'Special_Colours',
        'title' => esc_html__( 'Special Order Colours' ),
        'post_types' => array( 'product' ),
        'context' => 'advanced',
        'priority' => 'default',
        'autosave' => 'true',
        'fields' => array(
            array(
                'id' => 'special_colours',
                'type' => 'group',
                'group_title' => 'Colour {#}',
                'collapsible' => true,
                'save_state' => true,
                'clone'  => true,
                'sort_clone' => true,
                'fields' => array(
                    array(
                        'id'   => 'colour_name',
                        'type' => 'text',
                        'name' => 'Colour Name',
                    ),
                    array(
                        'id' => 'special_colour',
                        'type' => 'color',
                        'name' => esc_html__( 'Special Colour' ),
                        'desc' => esc_html__( 'Select a colour to appear on the product page as a special order colour' ),
                    ),
                ),
            ),
        ),
    );
    return $meta_boxes;
}

add_action( 'woocommerce_before_add_to_cart_button', 'product_special_colours', 5 );
function product_special_colours() { 
    $special_colours = rwmb_meta( 'special_colours' );
    if ( ! empty( $special_colours ) ) {
        echo '<table class="variations" cellspacing="0">
            <tbody>
                <tr>
                    <td class="label">
                        <label for="so_color">Special Order Colours</label>
                    </td>
                    <td class="value woo-variation-items-wrapper">
                        <ul class="variable-items-wrapper color-variable-wrapper">';

                            foreach ( $special_colours as $special_colour ) {
                                $colour_name = isset( $special_colour['colour_name'] ) ? $special_colour['colour_name'] : '';
                                if ( isset( $special_colour['special_colour'] ) ) {
                                    $colour = isset( $special_colour['special_colour'] ) ? $special_colour['special_colour'] : '';
                                    echo '<li class="special_colour" style="background-color: ' . $colour . ' ">
                                        <span class="tooltip">' . $colour_name . '</span>
                                    </li>';
                                }
                            }
                        echo '</ul>
                    </td>
                    <td>
                        <p>To order one of our special special order colours please <a href="/contact/">contact us</a>. <br> Please note that shipping of special orders can take up to 12 weeks.</p>
                    </td>
                </tr>
            </tbody>
        </table>';

    } 
}