Which should I use, -awakeFromNib or -viewDidLoad?

awakeFromNib is called when the controller itself is unarchived from a nib. viewDidLoad is called when the view is created/unarchived. This distinction is especially important when the controller's view is stored in a separate nib file.

Also important is that the awakeFromNib function will never be called after recovering from memory warning. But, the viewDidLoad function will be called.

Yes, it's correct. You shouldn't really rely on awakeFromNib to do that kind of tasks.

awakeFromNib is similar to an event that's called after deserialization in .NET. viewDidLoad is similar to Load event in .NET.

If you are familiar with the concepts from .NET, this should be enough, I think.

I'll try to answer by giving an example:

If define customCell class and customCell.xib file, and then load the cell by using
- (NSArray *)loadNibNamed:(NSString *)name owner:(id)owner options:(NSDictionary *)options, awakeFromNib gets called when the objects in the xib are unarchived.

If you define a customViewController, then when the customViewController is created using - (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil. viewDidLoad will get called when it's loaded into view hierarchy.

Some related confusing methods:

• (void)loadView; This is where subclasses should create their custom view hierarchy if they aren't using a nib. If you don't specify a nib name, then loadView will attempt to load a nib whose name is the same as your view controller's class. If no such nib exists, then you must either call -setView: before -view is invoked, or override the -loadView method to set up your views programatically. -loadView should never be called directly.

• (void)viewDidLoad: Called after the view has been loaded. For viewControllers created in code, this is after -loadView. For view controllers unarchived from a nib, this is after the view is set.