Programmatically change subviews from within subview's controller

In my iPhone application I've set up a default, blank view called Main View into which various child subviews will be loaded for different parts of the application. It's the same approach as if I was using a tool bar to switch between subviews. That case, in the MainView controller I could hook IBActions to buttons in the toolbar, so that when a button was pressed, MainView added different subviews to itself.

In my situation, though, I need to tell MainView to change its subview from within the su开发者_开发问答bviews. So here are two sister subviews, each with their own controller and xib, that would be loaded as subviews of MainView: - StartView - FormView

In StartView, after some animations and welcome stuff, a button triggers the camera image picker. Once the image picker returns the image, I need to tell MainView to remove StartView and add FormView.

It may be the result of a long day or my newness to iPhone OS but I'm stuck getting my head around the right way to set up my objects/controllers.

You never have more than one view controller active at a time. (The nav and tabbar controllers don't control views, they control other controllers.) In this case, you will have a single controller that has the MainView as its view property. It will add StartView and formView as subviews of MainView.

However, this is not a good design. It will overload the MainView controller by forcing it to juggle many views. It would be better to use a hidden navigation controller or a tabbar. Hierarchies of controllers can create the illusion from the users point of view for almost any interface layout you can imagine. There is no need to create a logical structure that mimics the visual one.

From your description you may only need a single view/view-controller pair: Set the formView controller to open the camera view before it displays the formView. When the camera is dismissed it reverts to the formView automatically. No fuss, no muss.