iphone – iOS 6.0中的界面方向

// Override to allow orientations other than the default porTrait orientation.
- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation 
{
    // Return YES for supported orientations
    return (interfaceOrientation == UIInterfaceOrientationLandscapeRight);
}

在iOS 6中替换，以及相当于上述弃用的iOS 5方法：

- (BOOL) shouldAutorotate
{
    return YES;
}

-(NSUInteger)supportedInterfaceOrientations
{
    return UIInterfaceOrientationMaskLandscapeRight;
}

希望这可以帮助。

[编辑#1：添加我的UIViewController成功地开始在肖像模式在XCode 4.5在iPhone 6.0模拟器]

#import "FirstViewController.h"

@interface FirstViewController ()

@end

@implementation FirstViewController

- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundLeorNil
{
    self = [super initWithNibName:nibNameOrNil bundle:nibBundLeorNil];

    if (self)
    {
        // Custom initialization
    }

    return self;
}

- (void)viewDidLoad
{
    [super viewDidLoad];
}

- (void)didReceiveMemoryWarning
{
    [super didReceiveMemoryWarning];
}

-(BOOL)shouldAutorotate
{
    return NO;
}

-(NSUInteger)supportedInterfaceOrientations
{
    return UIInterfaceOrientationMaskAll;
}

- (UIInterfaceOrientation)preferredInterfaceOrientationForPresentation
{
    return UIInterfaceOrientationMaskPorTrait;
}

[#edit 2：仅支持iOS 5和iOS 6的仅风景应用程序的示例代码]

- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation {

    return (interfaceOrientation == UIInterfaceOrientationLandscapeRight) || (interfaceOrientation == UIInterfaceOrientationLandscapeLeft);
}

- (BOOL)shouldAutorotate {

    return YES;
}

- (NSUInteger)supportedInterfaceOrientations {

    return UIInterfaceOrientationMaskLandscape;
}

- (UIInterfaceOrientation)preferredInterfaceOrientationForPresentation {

    return UIInterfaceOrientationLandscapeLeft;
}