如何在Swift Xcode8.2中以编程方式将导航控制器嵌入到选项卡栏控制器中？

Question

我一直在自学如何开发，我已经到了需要专家指导的地步。我使用MVC结构以编程方式创建了一些用户界面。我的问题是，如何将导航控制器嵌入到标签栏控制器中，以便标签栏控制器可以出现在每个屏幕上。我在main.storyboard中制作了标签栏控制器，并在名为Home Controller的视图控制器中引用了它。

    let storyboard: UIStoryboard = UIStoryboard(name: "Main", bundle: nil)

    let tabViewController = storyboard.instantiateViewController(withIdentifier: "TabBar")

    self.present(tabViewController, animated: true, completion: nil)

上面的代码是视图中的did加载函数。我想知道我是否需要在我的应用委托中更改根视图控制器？

    window = UIWindow(frame: UIScreen.main.bounds)
    window?.makeKeyAndVisible()

    let layout = UICollectionViewFlowLayout()      
    window?.rootViewController =  UINavigationController(rootViewController: HomeController(collectionViewLayout: layout))

这是在我完成的启动函数中。

Answer 1

使用以下几行

var navigationController = UINavigationController(rootViewController: viewController));

tabBarController.viewControllers = [navigationController,firstViewControllersecondViewController, ]

Answer 2

创建一个单独的UITabBarController类并在AppDelegate中对其进行初始化，如下所示：

func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?) -> Bool {
// Override point for customization after application launch.
      window = UIWindow(frame: UIScreen.main.bounds)

      window?.rootViewController = MyTabBarController()

      window?.makeKeyAndVisible()

      return true
}

和自定义的tabBarController

import UIKit

class MyTabBarController: UITabBarController {

    override func viewDidLoad() {
        super.viewDidLoad()


        self.tabBar.barTintColor = UIColor.black
        self.tabBar.tintColor = UIColor.white
        self.tabBar.unselectedItemTintColor = UIColor.white.withAlphaComponent(0.4)

        let firstViewController = FirstViewController()

        let firstViewTabBarItem = UITabBarItem(title: "First", image: UIImage(named: "calculator"), selectedImage: UIImage(named: "calculator"))

        firstViewController.tabBarItem = firstViewTabBarItem
        firstViewController.tabBarItem.tag = 0

        let historyViewController = HistoricDataViewController()

        historyViewController.tabBarItem = UITabBarItem(tabBarSystemItem: .history, tag: 1)

        let tabBarList = [calculateViewController, historyViewController]

        viewControllers = tabBarList.map{UINavigationController(rootViewController: $0)}

    }

}

希望这个例子能有所帮助。