ios - rightBarButtonItem未在物理设备上显示

我正在构建一个在rightBarButtonItem中具有购物车的电子商务应用程序。我已实现扩展以在每个UIViewControllers中添加购物车barButtonItem。我的barButtonItem在模拟器设备（包括iPhone 6s，iPhone SE和iPhoneX模拟器）中正确显示。没有在我的物理设备iPhone 6s上显示。有人可以帮助我如何跟踪此问题？感谢您的关注
这是我的代码

extension UIViewController{
    func addCartBarButtonItem(){
        let cartButton = UIButton(type: .custom)
        cartButton.setImage(UIImage(named:"cart"), for: .normal)
        cartButton.widthAnchor.constraint(equalToConstant: 28.0).isActive = true
        cartButton.heightAnchor.constraint(equalToConstant: 28.0).isActive = true
        cartButton.addTarget(self, action: #selector(self.goCheckOutController), for: .touchUpInside)
        let cartBarButtonItem = UIBarButtonItem(customView: cartButton)
        cartBarButtonItem.addBadge(number: CartDataManager.loadItems().count)
        self.navigationItem.rightBarButtonItem = cartBarButtonItem
    }
}

最佳答案

尝试这个，

var rightSearchBarButtonItem : UIBarButtonItem?

func addCartButtonToNavigationBar(){

    self.rightSearchBarButtonItem =  UIBarButtonItem(image: #imageLiteral(resourceName: "cart") , style: UIBarButtonItemStyle.plain, target: self, action: #selector(goCheckOutController))
    self.navigationItem.rightBarButtonItem = self.rightSearchBarButtonItem;
}

该代码对我有用