Magento结账步骤在Magento结账时付款前移动审核

I'd like to change the order of the One page checkout in Magento. I want to move the Review step before the Payment.

I've already changed the OnepageController to

 $stepCodes = array('billing', 'shipping', 'shipping_method', 'review', 'payment');

and saveShippingMethodAction in OnepageController to

            $result['goto_section'] = 'review';
            $result['update_section'] = array(

                'name' => 'review',

                'html' => $this->_getReviewHtml()

            );

However i'm getting error Fatal error: Call to a member function toHtml() on a non-object in D:\xampp\htdocs\cfh\app\code\core\Mage\Checkout\controllers\OnepageController.php on line 289

when I save the shipping method.

Any idea ?

thanks

Add $this->loadLayout('checkout_onepage_review'); before $result['update_section']