Question

every UIViewController has a method called willRotateToInterface.

Is it possible to do this within a UIView too?

Does this match the idea of model view controller ?

The only way I can think of is to send the event from the UIViewController to the UIView.

Is there a global variable for the current orientation?

Answer 1

Observe UIDeviceOrientationDidChangeNotification:

[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(orientationDidChange:) name:UIDeviceOrientationDidChangeNotification object:nil];

...

- (void)orientationDidChange:(NSNotification *)note
{
    NSLog(@"new orientation = %d", [[UIDevice currentDevice] orientation]);
}

UIDevice Class Reference

I should note that yo uneed to add -beginGeneratingDeviceOrientationNotifications when you want these notifications to be sent, and call -endGeneratingDeviceOrientationNotifications when you want them to stop. There is a battery impact of generating these, so you should only do so when your view is on screen. UIViewController does all this for you, so if you have a view controller, it is worth letting it do the work.