我的TableViewController中没有看到导航栏按钮项目

Question

我在main.storyboard中创建了一个UITableViewController，然后将其与名为MainMenu的类链接起来。在该类中，我手动添加了UIBarButtonItems以添加朋友并注销，但是我什么也没看到。我所看到的只是带有灰色线条的空白表格视图。

 class MainMenu: UITableViewController {

override func viewDidLoad() {
    super.viewDidLoad()



    navigationItem.leftBarButtonItem = UIBarButtonItem(title: "Logout", style: .plain, target: self, action: #selector(handleLogout))

    let image = UIImage(named: "add_friend_image")


    let menuButton = UIButton(type: .custom)
    menuButton.frame = CGRect(x: 0.0, y: 0.0, width: 20, height: 20)
    menuButton.setImage(image, for: .normal)
    menuButton.addTarget(self, action: #selector(handleFriend), for: UIControlEvents.touchUpInside) 

    let menuBarItem = UIBarButtonItem(customView: menuButton)
    let currWidth = menuBarItem.customView?.widthAnchor.constraint(equalToConstant: 24)
    currWidth?.isActive = true
    let currHeight = menuBarItem.customView?.heightAnchor.constraint(equalToConstant: 24)
    currHeight?.isActive = true;
    self.navigationItem.rightBarButtonItem = menuBarItem



}

Answer 1

1. 创建一个情节提要，然后添加您的TableViewController即MainMenu
2. 将MainMenu控制器嵌入Navigation Controller
3. 将导航控制器设置为初始视图控制器

4. 然后在viewDidLoad类的MainMenu中添加您的代码以设置导航栏按钮项

   class MainMenu: UITableViewController {
   
       override func viewDidLoad() {
           super.viewDidLoad()
   
           navigationItem.leftBarButtonItem = UIBarButtonItem(title: "Logout", style: .plain, target: self, action: #selector(handleLogout))
   
           let image = UIImage(named: "add_friend_image")
   
   
           let menuButton = UIButton(type: .custom)
           menuButton.frame = CGRect(x: 0.0, y: 0.0, width: 20, height: 20)
           menuButton.setImage(image, for: .normal)
           menuButton.addTarget(self, action: #selector(handleFriend), for: .touchUpInside)
   
           let menuBarItem = UIBarButtonItem(customView: menuButton)
           let currWidth = menuBarItem.customView?.widthAnchor.constraint(equalToConstant: 24)
           currWidth?.isActive = true
           let currHeight = menuBarItem.customView?.heightAnchor.constraint(equalToConstant: 24)
           currHeight?.isActive = true;
           self.navigationItem.rightBarButtonItem = menuBarItem
       }
   
       @objc func handleLogout() {
   
       }
   
       @objc func handleFriend() {
   
       }
   }
   

为情节提要文件添加了步骤，

输出为