Adicionar método de envio personalizado

add_filter('woocommerce_shipping_methods', 'add_custom_shipping_method');
function add_custom_shipping_method($methods) {
    $methods['custom_shipping'] = 'Custom_Shipping_Method';
    return $methods;
}

class Custom_Shipping_Method extends WC_Shipping_Method {
    public function __construct() {
        $this->id = 'custom_shipping';
        $this->method_title = 'Benutzerdefinierte Versandmethode';
        $this->method_description = 'Eine benutzerdefinierte Versandmethode für Testzwecke.';
        $this->enabled = 'yes';
        $this->init();
    }

    public function init() {
        $this->title = $this->get_option('title');
    }

    public function calculate_shipping($package = array()) {
        $rate = array(
            'id' => $this->id,
            'label' => $this->title,
            'cost' => 10.00,
            'calc_tax' => 'per_order',
        );

        $this->add_rate($rate);
    }
}