How do I manage models & views in an iPhone app?

Question

I have a bunch of model objects that inherit from NSObject (Result). And I have a bunch of view objects that inherit from UIView (ResultView). They exist in a 1:1 relationship (one model for one view). In my controller I have an two arrays: one for Result objects and one for ResultView objects. The controller displays many of these result views and they can be added/deleted/reordered. Trying to keep 2 arrays in sync (results & resultViews) isn't working out. How should I approach this problem?

I'm considering initializing a view object with a model object (eg: an initWithResult: in my ResultView class and then retain a pointer to the Result object in the ResultView). Then I could do something like ResultView.result to access model data. Is there a better solution? This would break MVC, wouldn't it?

Answer 1

Unless you're trying to persist these model objects in a DB or something similar, I would put a view property on the model objects. If you don't have to create the view for any reason, then just nil it out to save on memory.

Does it break MVC? I guess. But if your model objects will always have a view associated with them, it starts to go into the blurry line area. No programming god will send you to hell for breaking the standard a little bit.

Do what's clean, optimal, and easiest for another programmer to understand when looking at your code.

Answer 2

Ok, if I understand your question correctly, the model objects are persistent while the views are dynamically created/deleted. You are relying implicitly on the index of the two arrays to achieve the mapping of two parts. One simple way is to add a "model object id" in your view class. Then you can easily reference to the correct model object in the view.