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iOS Build a Photo Browser iPhone App View Controller Transitions Implementing Full Screen Transitions

Posted by Jack Raiden
Jack Raiden
7,976 Points

Sam set the ToViewControllerKey to be a UIViewController but it is actually a THDetailviewController, is it a problem?

when implement the - (void)animateTransition method, Sam wrote the first line like this

    UIViewController *detail=[transitionContext viewControllerForKey:UITransitionContextToViewControllerKey];

but in fact, the destination view controller is THDetailviewController, should we instead write this way:

    THDetailviewController *detail=[transitionContext viewControllerForKey:UITransitionContextToViewControllerKey];

or maybe I am entirely wrong, because THDetailviewController is a subclass of UIViewController, so what Sam wrote is totally fine... my instinct tells this may be the case, but I really want to know what is going on beneath it...

1 Answer

Michael Hulet
Michael Hulet
47,913 Points
Michael Hulet
Michael Hulet
47,913 Points

Your instinct is correct. Because THDetailViewController inherits from UIViewController, THDetailViewController is technically also a UIViewController therefore making this legal

Jack Raiden
Jack Raiden
7,976 Points

Thanks ! Yours words clears up doubts for me .