/**
  * column_default function.
  * 
  * @access public
  * @param mixed $post
  * @param mixed $column_name
  */
 public function column_default($item, $column_name)
 {
     global $wpdb;
     switch ($column_name) {
         case 'licence_key':
             return '<code>' . $item->licence_key . '</code>';
         case 'activation_email':
             return $item->activation_email;
         case 'product_id':
             $product = wppl_get_licence_product($item->product_id);
             return $product ? '<a href="' . admin_url('post.php?post=' . absint($product->ID) . '&action=edit') . '">' . esc_html($product->post_title) . '</a>' : __('n/a', 'wp-plugin-licencing');
         case 'user_id':
             $user = get_user_by('ID', $item->user_id);
             return $item->user_id ? '<a href="' . admin_url('user-edit.php?user_id=' . absint($item->user_id)) . '">#' . esc_html($item->user_id) . '&rarr;</a>' : __('n/a', 'wp-plugin-licencing');
         case 'activations':
             $count = $wpdb->get_var($wpdb->prepare("SELECT COUNT( activation_id ) FROM {$wpdb->prefix}wp_plugin_licencing_activations WHERE activation_active = 1 AND licence_key=%s;", $item->licence_key));
             return '<a href="' . admin_url('admin.php?page=wp_plugin_licencing_activations&amp;licence_key=' . $item->licence_key) . '">' . absint($count) . ' &rarr;</a>';
         case 'activation_limit':
             return $item->activation_limit ? sprintf(__('%d per product', 'wp-plugin-licencing'), absint($item->activation_limit)) : __('n/a', 'wp-plugin-licencing');
         case 'order_id':
             return $item->order_id > 0 ? '<a href="' . admin_url('post.php?post=' . absint($item->order_id) . '&action=edit') . '">#' . absint($item->order_id) . ' &rarr;</a>' : __('n/a', 'wp-plugin-licencing');
         case 'date_created':
             return $item->date_created ? date_i18n(get_option('date_format'), strtotime($item->date_created)) : __('n/a', 'wp-plugin-licencing');
         case 'date_expires':
             return $item->date_expires ? date_i18n(get_option('date_format'), strtotime($item->date_expires)) : __('n/a', 'wp-plugin-licencing');
     }
 }
<?php

if (sizeof($keys) > 0) {
    ?>
 

	<h2><?php 
    _e('Licence Keys', 'wp-plugin-licencing');
    ?>
</h2>
	<ul>
		<?php 
    foreach ($keys as $key) {
        $api_product = wppl_get_licence_product($key->product_id);
        ?>
			<li>
				<?php 
        echo esc_html($api_product->post_title);
        ?>
: <strong><?php 
        echo $key->licence_key;
        ?>
</strong>
				<?php 
        if ($api_product_permissions = wppl_get_licence_api_product_permissions($key->product_id)) {
            echo '<ul class="digital-downloads">';
            foreach ($api_product_permissions as $api_product_permission) {
                echo '<li><a class="download-button" href="' . wppl_get_package_download_url($api_product_permission, $key->licence_key, $key->activation_email) . '">' . sprintf(__('Download %s', 'wp-plugin-licencing'), get_the_title($api_product_permission)) . '</a></li>';
            }
            echo '</ul>';
        }