1.將addSubview修改為setRootViewController

[window addSubview: viewController.view];修改如下：

if ( [[UIDevice currentDevice].systemVersion floatValue] < 6.0)
{
    // warning: addSubView doesn't work on iOS6
    [window addSubview: viewController.view];
}
else
{
    // use this mehod on ios6
    [window setRootViewController:viewController];
}
2.修改shouldAutorotateToInterfaceOrientation

- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation
{
    return UIInterfaceOrientationIsLandscape( interfaceOrientation );
}

iOS6以前會呼叫這方法來判斷手機是垂直或打橫

// For ios6, use supportedInterfaceOrientations & shouldAutorotate instead of shouldAutorotateToInterfaceOrientation
- (NSUInteger) supportedInterfaceOrientations{
    return UIInterfaceOrientationMaskLandscape;
}

- (BOOL) shouldAutorotate {
    return YES;
}
iOS6需在加上上面方法