Passing an Object backward to a ViewController

        NSArray* viewControllers = self.navigationController.viewControllers;

        

        OrderDetailsViewController* previousVC = [viewControllers objectAtIndex:[viewControllers count] - 2];

        

        self.orderDetails.cashOrCredit = @"cash";

        

        previousVC.orderDetails = self.orderDetails;

        

        [self.navigationController popViewControllerAnimated:YES];