检测手机翻转

代码：

- (void)viewDidLoad {
    [super viewDidLoad];
    // Do any additional setup after loading the view, typically from a nib.

    //监听手机方向改变事件
    [[NSNotificationCenter defaultCenter] addObserver:self
                                             selector:@selector(orientationChanged)
                                                 name:UIDeviceOrientationDidChangeNotification
                                               object:nil];
}

#pragma -mark -functions
//处理函数
-(void) orientationChanged
{
    switch ([[UIDevice currentDevice] orientation]) {
        case UIDeviceOrientationPortrait:
            NSLog(@"portrait");
            break;
        case UIDeviceOrientationPortraitUpsideDown:
            NSLog(@"portraitUpSideDown");
            break;
        case UIDeviceOrientationLandscapeLeft:
            NSLog(@"landscapeLeft");
            break;
        case UIDeviceOrientationLandscapeRight:
            NSLog(@"landscapeRight");
            break;
        case UIDeviceOrientationFaceDown:
            NSLog(@"facedown!!");
            break;
        case UIDeviceOrientationFaceUp:
            NSLog(@"FaceUp");
            break;
        default:
            break;
    }
}