Help with a deep copy

Question

What is the best practice for sending doing a deep copy between two View Controllers in an iPhone app. I've designed an app that sends over arrays of arrays and the deeper items aren't coming over as easily as I thought. Do you explicitly copy? Just alloc placeholders and set them equal? Links to any samples would be greatly appreciated.
Is it a best practice to avoid that kind of data passing - as being overly complex?
Background:
I'm building an iPhone application where I need to send a complex object from one view controller to another - This complex object is an array of arrays of objects.
I can't just copy a reference to the complex object over to a variable on the receiving view controller, as none of the nested array contents come over.
So I think I need to do a deep copy - but need advice on best practices for that. The array of arrays contain objects, so ideally, Id just be able to :
Thanks for any advice!

Answer 1

There are many ways of solving this.
One way is to centralize the information:
You create a singleton class that is the datasource for both view, so you don't need to pass in anything. If you can't do that because the datasources are generally different except for this specific array of arrays, then make the singleton class be the source of that array and nothing else.