ios - Passing data from the FirstViewController to the LastViewController

Question

I have four viewControllers in my current design and I am designing an app to sell a product.

FirstViewController gets the product image and when user clicks to the next button then it takes user to the secondviewcontroller where user describes the product and then user clicks next button which takes user to the thirdViewcontroller where price and condition are entered. In the lastviewcontolller there is a post button to send the product info to the server. I am using POST method.

The following segue approach does not fit into what I want, because it sends the firstviewcontroller object (product image) to the secondviewcontoller, and then secondviewcontroller also should forward the product image to the thirdviewcontoller and so on. I do not think it is a feasible way of doing it.

I wonder what is the best way of collection information from the first page till to the last page and send it. What is best way of handling that issue? I am using segue between the viewcontrollers.

- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender
{
    // Make sure your segue name in storyboard is the same as this line
    if ([[segue identifier] isEqualToString:@"isSecond"])
    {
        // Get reference to the destination view controller
        SecondViewController *vc = [segue destinationViewController];

        // Pass any objects to the view controller here, like...
        [vc setMyProductImage:productImage];
    }
}

Answer 1

Create an object to act as your application's data model. It can be a singleton or it can be a normal object that's available from a known location...such as owned by the app delegate.

Update your model when you have new information and read from the model when you need to display something. Using prepareForSegue: and linking controllers may be acceptable for simple things but it really doesn't scale well.