Objective-c – how to detect the iPhone orientation before rotating

cocoa-touchiphoneiphone-sdk-3.0objective c

In my program I'm moving things based on rotation, but I'm not rotating the entire view. I'm Using :

  static UIDeviceOrientation previousOrientation = UIDeviceOrientationPortrait;

 - (void)applicationDidFinishLaunching:(UIApplication *)application {   
    [window addSubview:viewController.view];
    [window makeKeyAndVisible];
    [[NSNotificationCenter defaultCenter] addObserver:self
           selector:@selector(didRotate:)
           name:@"UIDeviceOrientationDidChangeNotification" object:nil];

}

- (void) didRotate:(NSNotification *)notification{  
UIDeviceOrientation orientation = [[UIDevice currentDevice] orientation];

    [self doRotationStuff:orientation: previousOrientation];
previousOrientation = orientation;

}

This works as long as, when the program is launched, the device orientation is portrait, but not if the initial orientation is landscape or upside down, because [self doRotationStuff] makes changes relative to the difference from the previous orientation.

Is there a way to detect the orientation either at launch, or right before the device is rotated?

Best Answer

Depending on your circumstances, a simpler option may be the interfaceOrientation property of the UIViewController class. This is correct before a rotation.

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