ios - UIBarButtonItem 横向定位

Question

我有一个 iPad 应用程序，它在纵向时可以正常工作。然而，在横向（即使被迫只使用横向）中，我添加的 UIBarButtonItems 看起来稍微靠右，以至于它们部分地从屏幕的右侧消失。这是我用来创建和添加按钮的代码片段：

-(void)viewDidLoad
{
    AppDelegate *app = [[UIApplication sharedApplication] delegate];
    UIImageView *iv = [[UIImageView alloc] initWithImage:[UIImage imageNamed:@"bg.png"]];
    [self.view addSubview:iv];
    SDZFESServices *service = [SDZFESServices service];
    [service setServiceUrl:[app serviceUrl]];
    [service GetSeatingPlan:self action:@selector(SeatingPlanReturn:) group_id:[group ItemID] group_type:@"COU"];
    self.title = [NSString stringWithFormat:@"Seating plan: %@", [group ItemName]];
    UIBarButtonItem *bbi = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemSave target:self action:@selector(SaveSeatingPlan:)];
    [self.navigationItem setRightBarButtonItem:bbi];

}

有任何想法吗？只有按钮的左半部分可见。