从推送视图返回后，导航栏按钮消失

Question

我在顶部栏设置上有4个按钮，使用leftBarButtonItems和rightBarButtonItems的按钮数组。当我推到另一个视图并返回时按钮消失了。按钮所在的区域未激活（无法选择）。如果我将应用程序放在后台并将其恢复到前台，则会恢复按钮。

有什么建议吗？

由于

以下是初始化按钮的代码：

- (void)viewDidLoad
{
    [super viewDidLoad];

    UIBarButtonItem *selectButton          = [[UIBarButtonItem alloc] initWithTitle:@"Select" style:UIBarButtonItemStylePlain target:self action:@selector(selectPlayers:)];
    UIBarButtonItem *manageButton          = [[UIBarButtonItem alloc] initWithTitle:@"Manage" style:UIBarButtonItemStylePlain target:self action:@selector(managePlayers:)];

    self.navigationItem.rightBarButtonItems =
    [NSArray arrayWithObjects:manageButton, selectButton, nil];

    UIBarButtonItem *TeamsButton          = [[UIBarButtonItem alloc] initWithTitle:@"Teams" style:UIBarButtonItemStylePlain target:self action:@selector(CreateTeams:)];

    UIBarButtonItem *TransferButton          = [[UIBarButtonItem alloc] initWithTitle:@"Transfer" style:UIBarButtonItemStylePlain target:self action:@selector(Transfer:)];

    self.navigationItem.leftBarButtonItems =
    [NSArray arrayWithObjects:TeamsButton,TransferButton, nil];

}

我找到了解决方法。问题视图隐藏了状态栏。推送视图显示状态栏。如果我还隐藏了推动视图上的状态栏，则按钮不再消失。这看起来像是xcode或IOS中的错误。