连接到tabbarcontroller时，无法在swift 4.2的导航栏中显示barbutton项目吗？

Question

我已这样链接navigationController和tabBarController

let mainStoryboard: UIStoryboard = UIStoryboard(name: "Main", bundle: nil)
let viewController = mainStoryboard.instantiateViewController(withIdentifier: "TabAction") as UIViewController
self.window = UIWindow(frame: UIScreen.main.bounds)
self.window?.rootViewController = UINavigationController(rootViewController: TabBarController())
self.window?.makeKeyAndVisible()
let navigationController = UINavigationController.init(rootViewController: viewController)
UIApplication.shared.keyWindow?.rootViewController = viewController
self.window?.rootViewController = navigationController
self.window?.makeKeyAndVisible()

视图控制器中的barbutton项目的代码：

super.viewDidLoad()
    // registering table
    recruitmentDbView?.register(UINib(nibName: "recruitmentDashboardCell", bundle: nil), forCellReuseIdentifier: "CustomCell")
    // setting colour to navigation bar
    self.navigationController?.navigationBar.barTintColor = UIColor(red: 18/255, green: 41/255, blue: 50/255, alpha: 1)
    // setting barbutton items on navigation bar
    let rightFilterBarButtonItem: UIBarButtonItem = UIBarButtonItem(image: UIImage(named: "FilterIcon"), style: .plain, target: self, action: nil)
    rightFilterBarButtonItem.tintColor = UIColor.white
    let rightSearchBarButtonItem: UIBarButtonItem = UIBarButtonItem(image: UIImage(named: "SearchIcon"), style: .plain, target: self, action: nil)
    rightSearchBarButtonItem.tintColor = UIColor.white

    self.navigationItem.rightBarButtonItems = [rightFilterBarButtonItem,rightSearchBarButtonItem]
    self.navigationItem.leftBarButtonItem?.isEnabled = true
    self.navigationItem.backBarButtonItem?.isEnabled = false
    let leftBackBarButtonItem: UIBarButtonItem = UIBarButtonItem(image: UIImage(named: "BackIcon"), style: .plain, target: self, action: nil)
    self.navigationItem.leftBarButtonItem = leftBackBarButtonItem
    self.navigationItem.title = "Recruit - Dashboard"

    let textAttributes = [NSAttributedString .Key.foregroundColor:UIColor.white]
    self.navigationController?.navigationBar.titleTextAttributes = textAttributes
}

Answer 1

尝试此代码：-

let button1 = UIBarButtonItem(image: UIImage(named: "imagename"), style: .plain, target: self, action: selector: #selector(action1)) // 
self.navigationItem.rightBarButtonItem  = button1


let filterIcon    = UIImage(named: "FilterIcon")!
let searchImage  = UIImage(named: "SearchIcon")!

let rightFilterBarButtonItem  = UIBarButtonItem(image: filterIcon,  style: .Plain, target: self, selector: #selector(action2))
let rightSearchBarButtonItem = UIBarButtonItem(image: searchImage,  style: .Plain, target: self, selector: #selector(action3))

 navigationItem.rightBarButtonItems = [rightFilterBarButtonItem, rightFilterBarButtonItem]


 @objc func action1()
    {

    }
    @objc func action2()
    {
      ProgressViewVc.sharedInstance.showProcessView()
    }

 @objc func action3()
    {
      ProgressViewVc.sharedInstance.showProcessView()
    }