问如何使用统一故事板在iPad中将一个屏幕限制为纵向模式，而将其他屏幕限制为横向模式(Xcode6)

EN

-(void)viewWillAppear:(BOOL)animated
    {
      [self willAnimateRotationToInterfaceOrientation:[UIApplication sharedApplication].statusBarOrientation duration:.2];
      [self awakeFromNib];

    }
    -(void)viewWillDisappear:(BOOL)animated {

      [[NSNotificationCenter defaultCenter] removeObserver:self                                                                                      name:UIDeviceOrientationDidChangeNotification
                                                    object:nil];
    }
    - (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)toInterfaceOrientation
    {
      if(is_iPad)
      {
        return YES;
      }else
      {
        return (UIInterfaceOrientationIsPortrait(toInterfaceOrientation));
      }
    }


- (void)awakeFromNib

{
  AppDelegate  *delegate = (AppDelegate *)[[UIApplication sharedApplication]delegate];
  delegate->isShowingLandscapeView=NO;

  [[UIDevice currentDevice] beginGeneratingDeviceOrientationNotifications];

  [[NSNotificationCenter defaultCenter] addObserver:self

                                           selector:@selector(orientationChanged:)

                                               name:UIDeviceOrientationDidChangeNotification

                                             object:nil];

}

- (void)orientationChanged:(NSNotification *)notification
{
  if (is_iPad) {
    AppDelegate  *delegate = (AppDelegate *)[[UIApplication sharedApplication]delegate];
    UIDeviceOrientation deviceOrientation = [UIDevice currentDevice].orientation;
    if (UIDeviceOrientationIsLandscape(deviceOrientation) &&
        !delegate->isShowingLandscapeView)
    {
      yourPotraitViewController *ypvc =[[yourPotraitViewController alloc] initWithNibName:@"yourPotraitViewController" bundle:nil];


      [self.navigationController pushViewController:objHomeLandscape animated:YES];
      delegate->isShowingLandscapeView=YES;
      // isShowingLandscapeView = YES;
    }
    else if (UIDeviceOrientationIsPortrait(deviceOrientation) &&
             delegate->isShowingLandscapeView)
    {
      [self.navigationController popViewControllerAnimated:YES];
      delegate->isShowingLandscapeView=NO;
    }
  }
}