我正在尝试将导航按钮添加到 UITabController 的顶部栏,但该按钮未显示。
UIBarButtonItem * leftButtonItem = [[UIBarButtonItem alloc] initWithTitle: @"SETTING" style: UIBarButtonItemStyleBordered target: self action: @selector(permanentlyCloseWelcomeView)] ;
[[self navigationItem] setLeftBarButtonItem: leftButtonItem];