ios - Swift-以编程方式导航 Controller 和选项卡栏 Controller

Question

我正在以编程方式编写一个带有选项卡栏和导航 Controller 的应用程序，我已经删除了 Storyboard，该应用程序也运行良好，并且当“secondViewController”不是 mainNavigationController.viewControllers 数组的一部分时显示导航栏，但是，当我添加 secondaryViewController 时，导航栏不会显示在 View 上。我可能做错了什么而没有显示导航栏？我应该将 mainNavigationController 设置为 rootViewController 吗？

    let mainNavigationController = MainNavigationController()
    let mainTabBarController = MainTabBarController()
    let mainViewController = MainViewController()
    let secondViewController = SecondViewController()

    mainNavigationController.title = "Single Meal"
    secondViewController.title = "Group Meal"
    mainViewController.title = "Single Meal"

    mainNavigationController.viewControllers = [mainViewController, secondViewController]
    mainTabBarController.viewControllers = [mainNavigationController, secondViewController]

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

Answer 1

试试这个

let mainNavigationController = MainNavigationController()
let secondNavigationController = UINavigationController(rootViewController: secondViewController)
let mainTabBarController = UITabBarController()
let mainViewController = MainViewController()
let secondViewController = SecondViewController()

mainNavigationController.title = "Single Meal"
secondViewController.title = "Group Meal"
mainViewController.title = "Single Meal"

mainNavigationController.viewControllers = [mainViewController, secondViewController]

mainTabBarController.viewController = [mainNavigationController, secondNavigationController]

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

以您的方式，当您选择第二个选项卡时， SecondViewController 实际上并未嵌入导航 Controller 中，但是当您使用导航 Controller 上的推送从 mainViewController 转到 secondaryViewController 时，第二个 View Controller 将显示在 mainViewController 的顶部