判断设备的代码

if ([[UIDevicecurrentDevice] userInterfaceIdiom] ==UIUserInterfaceIdiomPhone) {

      self.viewController = [[RAViewControlleralloc] initWithNibName:@"RAViewController_iPhone"bundle:nil];

  } else {

      self.viewController = [[RAViewControlleralloc] initWithNibName:@"RAViewController_iPad"bundle:nil];

  }