swift - 在导航 Controller 和 TabbarController 中呈现 View Controller

Question

来自一个单独的 IntroViewController，我试图展示一个嵌入在 UINavigationController 中的 UIViewController，它也是 UITabbarController 中的三个选项之一。

let tabVC = storyboard?.instantiateViewController(withIdentifier: "TabBarViewController")
self.present(UINavigationController(rootViewController: tabVC!), animated: true, completion: nil)

当我向我的 View Controller 显示上面的代码时，导航 Controller 不完整，缺少所有 View Controller 中的栏项(参见图片)。

我已经研究了几个小时，只能显示 TabbarController 或 UINavigationController，但不能同时显示两者。谢谢你的帮助。非常感谢!

更新:我应该澄清一下，只有当我尝试从另一个 View Controller 呈现它时，问题才会存在。当我将它用作初始 View Controller 时，一切都很好。

Answer 1

使用此代码在 tabBar Controller 类中初始化您的 viewControllers。我为每个 viewController 和 tabBarButton 使用不同的 Storyboard，但你也可以从一个 Storyboard初始化它们，只需在 makeTabBarItemForViewController 方法中初始化右 View Controller

private func loadViewControllers(animated: Bool){

    var viewControllers = [UIViewController]()
    viewControllers.append(self.makeTabBarItemForViewController(storyboardIdentifier: "CurrentChannels", title: LocalizationUtil.localizedString(forKey: "On Air"), selectedImageName: Assets.tabBarIconOnAir.rawValue, imageName: Assets.tabBarIconOnAirUnselected.rawValue))
    self.viewControllers = viewControllers;
    self.setViewControllers(viewControllers, animated: animated)
}


private func makeTabBarItemForViewController(storyboardIdentifier: String,title:String , selectedImageName:String , imageName:String)-> UIViewController{
    let storyboard = UIStoryboard(name: storyboardIdentifier, bundle: nil)
    let vc:UIViewController? = storyboard.instantiateInitialViewController();
    let selectedImage = UIImage(named: imageName)?.withRenderingMode(.alwaysOriginal)
    let notSelectedImage = UIImage(named:selectedImageName)?.withRenderingMode(.alwaysOriginal)
    let item = UITabBarItem(title: title, image: selectedImage, selectedImage: notSelectedImage)
    vc!.tabBarItem = item

    if let navVC = vc as? UINavigationController{
        navVC.delegate = self
    }
    return vc!
}