When to load data in UITableViewController?

I am currently loading data coming from a JSON service in the viewDidLoad method in UITableViewController. The problem is that is the data takes time to be retrieved and parsed, the view takes time to be created. Where is the best place to load this data? I assume that there is a hook somewhere to load data after the view is created. By doing this I will be able to use some UIActivityIndicatorView in the final view. Thanks