UIDevice orientation keeps flipping between UIDeviceOrientationPortrait and UIDeviceOrientationLandscapeRight when I put my phone flat

Question

I'm quite confused about the device orientation value when I put my phone flat. I registered a observer for UIDeviceOrientationDidChangeNotification, and called beginGeneratingDeviceOrientationNotifications to observer device orientation change. Everything works fine until I put my phone flat on desktop.

Here's the code in my project:

- (void)deviceDidRotate:(NSNotification *)notification
{
    UIDevice *currentDevice = [UIDevice currentDevice];
    NSLog(@"Orientation: %d", currentDevice.orientation);
}

And the log gives me this:

2013-12-29 12:14:28.121 MyProject[1140:60b] Orientation: 5
2013-12-29 12:14:28.764 MyProject[1140:60b] Orientation: 1
2013-12-29 12:14:31.609 MyProject[1140:60b] Orientation: 4
2013-12-29 12:14:33.377 MyProject[1140:60b] Orientation: 1
2013-12-29 12:14:33.574 MyProject[1140:60b] Orientation: 4
2013-12-29 12:14:33.770 MyProject[1140:60b] Orientation: 1
2013-12-29 12:14:33.868 MyProject[1140:60b] Orientation: 4
2013-12-29 12:14:34.065 MyProject[1140:60b] Orientation: 1
2013-12-29 12:14:34.164 MyProject[1140:60b] Orientation: 4
2013-12-29 12:14:34.455 MyProject[1140:60b] Orientation: 1
2013-12-29 12:14:34.555 MyProject[1140:60b] Orientation: 4
    repeating...

The first 5 is quite reasonable, since I've put my phone face up, but the 1s (represent UIDeviceOrientationPortrait) and 4s (represent UIDeviceOrientationLandscapeRight) are quite confusing.

My question is how to fix this problem?

Answer 1

I had a same problem, following solution fixed this issue:

Add following methods in each viewController (with your preferred orientation)

- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation {

    return (interfaceOrientation == UIInterfaceOrientationLandscapeLeft);
}

- (BOOL)shouldAutorotate {

    return NO;
}

- (NSUInteger)supportedInterfaceOrientations {

    return UIInterfaceOrientationMaskLandscape;
}

- (UIInterfaceOrientation)preferredInterfaceOrientationForPresentation {

    return UIInterfaceOrientationLandscapeLeft;
}

and in AppDelegate as well with following line of code in didFinishLaunchingWithOptions

[[UIDevice currentDevice] beginGeneratingDeviceOrientationNotifications];
[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(preferredInterfaceOrientationForPresentation) name:@"UIDeviceOrientationDidChangeNotification" object:nil];