How do I detect a rotation on the iPhone without t

问题:

Anyone know how to do this?

I thought this:

-(BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation {
    return YES;
}

- (void)willRotateToInterfaceOrientation:(UIInterfaceOrientation)toInterfaceOrientation duration:(NSTimeInterval)duration {
}

- (void)willAnimateRotationToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation duration:(NSTimeInterval)duration {
}

- (void)didRotateFromInterfaceOrientation:(UIInterfaceOrientation)fromInterfaceOrientation {
}

- (void)willAnimateFirstHalfOfRotationToInterfaceOrientation:(UIInterfaceOrientation)toInterfaceOrientation duration:(NSTimeInterval)duration {
}

- (void)didAnimateFirstHalfOfRotationToInterfaceOrientation:(UIInterfaceOrientation)toInterfaceOrientation {
}

- (void)willAnimateSecondHalfOfRotationFromInterfaceOrientation:(UIInterfaceOrientation)fromInterfaceOrientation duration:(NSTimeInterval)duration {
}

may prevent the device from rotation (overriding all rotate methods of my UIViewController and not calling the superclass) but I fear it's not the UIViewController that actually performs the rotation.

My UIViewController is in a UINavigationController.

Anyone have any ideas?

Cheers, Nick.

回答1:

You can register for the notification UIDeviceOrientationDidChangeNotification (from UIDevice.h), and then when you care about orientation changes call this method:

[[UIDevice currentDevice] beginGeneratingDeviceOrientationNotifications];

When you no longer care about orientation changes, call this method:

[[UIDevice currentDevice] endGeneratingDeviceOrientationNotifications];

The notification will be sent when applicable, and you can check [UIDevice currentDevice].orientation to find out what the current orientation is.

回答2:

On a side note shouldAutoRotateToInterfaceOrientation used to be called on the time for rotation in 2.x, but in 3.0 it's much less consistent. The notification mentioned in the other post is the way to go for reliable indication of rotation.

回答3:

You're returning YES from shouldAutorotateToInterfaceOrientation:, which I suspect you didn't mean to do. That's the only method you need to implement to prevent the device from rotating.

As for getting the current orientation of the device, you can use [[UIDevice currentDevice] orientation].