//self.cameraView是相机view - (NSUInteger)supportedInterfaceOrientations{    UIInterfaceOrientation e = [[UIApplication sharedApplication] statusBarOrientation];    if (e == UIInterfaceOrientationLandscapeLeft) {                if (self.cameraView) {            self.cameraView.transform = CGAffineTransformMakeRotation((-270 * M_PI) / 180.0f);        }    }else if (e == UIInterfaceOrientationLandscapeRight) {                if (self.cameraView) {            self.cameraView.transform = CGAffineTransformMakeRotation((270 * M_PI) / 180.0f);        }            }    return (UIInterfaceOrientationMaskLandscape);}  - (void)viewDidLoad{    [super viewDidLoad];    // Do any additional setup after loading the view.    //m_bScreen是bool 型，判断横竖屏。    if ([[[UIDevice currentDevice]systemVersion ]floatValue]  >= 8.0) {        BOOL m_bScreen = NO;                UIInterfaceOrientation e = [[UIApplication sharedApplication] statusBarOrientation];        if (e == UIInterfaceOrientationLandscapeLeft) {            m_bScreen = NO;        }else if (e == UIInterfaceOrientationLandscapeRight) {            m_bScreen = YES;        }        if ([[UIDevice currentDevice] respondsToSelector:@selector(setOrientation:)]) {                        NSNumber *num = [[NSNumber alloc] initWithInt:(m_bScreen?UIInterfaceOrientationLandscapeRight:UIInterfaceOrientationLandscapeLeft)];                        [[UIDevice currentDevice] performSelector:@selector(setOrientation:) withObject:(id)num];                        [UIViewController attemptRotationToDeviceOrientation];//这行代码是关键                    }        SEL selector=NSSelectorFromString(@"setOrientation:");                NSInvocation *invocation =[NSInvocation invocationWithMethodSignature:[UIDevice instanceMethodSignatureForSelector:selector]];                [invocation setSelector:selector];                [invocation setTarget:[UIDevice currentDevice]];                int val =m_bScreen?UIInterfaceOrientationLandscapeRight:UIInterfaceOrientationLandscapeLeft;                [invocation setArgument:&val atIndex:2];                [invocation invoke];    }        }

#pragma mark UINavigationControllerDelegate- (void)navigationController:(UINavigationController *)navigationController willShowViewController:(UIViewController *)viewController animated:(BOOL)animated{    if ([[[UIDevice currentDevice]systemVersion ]floatValue]  >= 8.0) {        UIView *PLCameraView=[self findView:viewController.view withName:@"PLImagePickerCameraView"];        NSArray *svarray = [PLCameraView subviews];        self.imagePickerController.cameraView = svarray[0];        for (int i = 1; i < svarray.count; i++)  { //i: 0 相机 1 拍照界面 2 重拍界面            if (i == 1) {                NSArray *arr = [svarray[1] subviews];                for (int i = 0; i < arr.count; i++) {                    if (i == 9) { //i: 1 前置摄像头切换                        [[arr objectAtIndex:i] setAlpha:0.0f];                    }                }            }        }    }else if ([[[UIDevice currentDevice]systemVersion ]floatValue]  >= 7.0) {        UIView *PLCameraView=[self findView:viewController.view withName:@"PLCameraView"];        NSArray *svarray = [PLCameraView subviews];        for (int i = 1; i < svarray.count; i++)  { //i: 0 相机 1 拍照界面 2 重拍界面            if (i == 1) {                NSArray *arr = [svarray[1] subviews];                for (int i = 0; i < arr.count; i++) {                    if (i == 1) { //i: 1 前置摄像头切换                        [[arr objectAtIndex:i] setAlpha:0.0f];                    }                }            }        }    }}#pragma mark get/show the UIView we want//Find the view we want in camera structure.-(UIView *)findView:(UIView *)aView withName:(NSString *)name{    Class cl = [aView class];    NSString *desc = [cl description];        if ([name isEqualToString:desc])        return aView;        for (NSUInteger i = 0; i < [aView.subviews count]; i++)    {        UIView *subView = [aView.subviews objectAtIndex:i];        subView = [self findView:subView withName:name];        if (subView)            return subView;    }    return nil;}