Under what circumstances would [ [ UIApplication sharedApplication ] keyWindow ] return nil?

Question

In some cases [[ UIApplication sharedApplication] keyWindow ] returns nil.

On some devices it's happening pretty often but in general it's sporadic

Anyone know the reasons it would return nil?

Answer 1

...When happens a transition form one window to another, i suppose. Users can't see any transitions, but they happen.

In iPhone OS 2.0 to iPhone 3.1.3, one example is immediately after you sent the message play to a MPMoviePlayerController instance:

[[[MPMoviePlayerController alloc]initWithContentURL:[@"http://someurl"]]play];

There might be also other situations.