UIDeviceOrientationDidChangeNotification only fires once - objective-c

Question

I am trying to handle device orientation changes on a viewcontroller for one of my views.
Here is my code:
- (void)viewDidLoad {
[super viewDidLoad];
NSLog(#"viewDidLoad");
// Tell the UIDevice to send notifications when the orientation changes
[[UIDevice currentDevice] beginGeneratingDeviceOrientationNotifications];
[[NSNotificationCenter defaultCenter] addObserver:self selector:#selector(orientationChanged:) name:UIDeviceOrientationDidChangeNotification object:nil];
}
// tell the director that the orientation has changed
- (void) orientationChanged:(NSNotification *)notification
{
NSLog(#"orientationChanged");
}
When I first launch the App, the orientationChanged selector gets called, but then after that it does not get called again no matter how much I rotate the iPad. Does anyone have any idea what I might be doing wrong? When I put similar code in the app delegate, it works fine, but in this particular view controller, it is not behaiving properly.

Answer 1

I know this question is a bit old, but just thought I'd add a link to a tutorial I found when I was in the same situation you were (wanting to get notifications for device rotation, regardless of what the interface orientation was).
This tutorial gives a nice and simple overview of how to handle device rotation using UIDeviceOrientationDidChangeNotification.
I also had issues with UIDeviceOrientationDidChangeNotification not firing (it worked fine in the simulator, but not on my device). After a bit of debugging I realised that I had Portrait Orientation Locked on the device, and this was causing the UIDeviceOrientationDidChangeNotification not to fire. Not sure if that's your issue, but it's something that's easy to overlook and worth checking.

Answer 2

the problem is that the orientation will not change unless you specify that it can do so. when you rotate the device/simulator, the framework calls
- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation;
where interface orientation is the orientation the system wants to use, however you have to return YES or it will not change.
if you are not returning YES then your orientation is not changing and therefore you cannot get notified for an orientation change (because it did not happen)