无法在IOS6中设置StatusBarorientaion

使用UINavigationController时，方向状态不会更改。 这是我的代码：

AppDelegate.h文件

#import <UIKit/UIKit.h>
@class MainViewController;
@interface AppDelegate : UIResponder<UIApplicationDelegate>
@property (strong, nonatomic) UIWindow *window;
@property (strong, nonatomic) MainViewController *mainViewController;
@end

MainViewController.m

...
-(NSUInteger)supportedInterfaceOrientations{
    return  UIInterfaceOrientationMaskLandscapeLeft;
}
-(UIInterfaceOrientation)preferredInterfaceOrientationForPresentation{
    return UIInterfaceOrientationMaskLandscapeLeft;
}
-(BOOL)shouldAutorotate{
    return YES;
}
-(void) viewDidAppear:(BOOL)animated {

    [UIApplication sharedApplication].statusBarOrientation = UIInterfaceOrientationLandscapeLeft;
    [self.navigationController setNavigationBarHidden:YES];
}
...

---

从iOS 6.0 SDK发行说明：

SetStatusBaroOrientation:animated:方法并没有完全被弃用。现在，仅当最顶端的全屏视图控制器的supportedInterfaceOrientations方法返回0时，它才起作用。这使得调用者负责确保状态栏方向一致

...
-(NSUInteger)supportedInterfaceOrientations{
    return  UIInterfaceOrientationMaskLandscapeLeft;
}
-(UIInterfaceOrientation)preferredInterfaceOrientationForPresentation{
    return UIInterfaceOrientationMaskLandscapeLeft;
}
-(BOOL)shouldAutorotate{
    return YES;
}
-(void) viewDidAppear:(BOOL)animated {

    [UIApplication sharedApplication].statusBarOrientation = UIInterfaceOrientationLandscapeLeft;
    [self.navigationController setNavigationBarHidden:YES];
}
...