显示来自TabBarController的特定TabBarController

Question

每当触发本地通知并执行它们的自定义操作时，我都希望从TabBarController打开一个特定的TabBarController。我使用了下面的代码行

func userNotificationCenter(_ center: UNUserNotificationCenter, didReceive response: UNNotificationResponse, withCompletionHandler completionHandler: @escaping () -> Void) {

    switch response.actionIdentifier {
    case "first":
        DispatchQueue.main.async(execute: {
            self.first()
        })
    case "second":
        DispatchQueue.main.async(execute: {
            self.second()
        })
    default:
        break
    }


    completionHandler()
}

所以这是一个first()函数

 func first() {


    let storyboard = UIStoryboard.init(name: "Main", bundle: nil)
    let tabBarController = storyboard.instantiateViewController(withIdentifier: "Root") as! UITabBarController
    let navigationController = storyboard.instantiateViewController(withIdentifier: "First") as! UINavigationController

    tabBarController.present(navigationController, animated: true) { 

    }

    self.window = UIWindow.init(frame: UIScreen.main.bounds)
    self.window?.tintColor = UIColor(red: 0.0, green: 0.5, blue: 0.0, alpha: 1.0)
    self.window?.rootViewController = tabBarController
    self.window?.makeKeyAndVisible()

}

第二个功能：second()

func second() {


    let storyboard = UIStoryboard.init(name: "Main", bundle: nil)
    let tabBarController = storyboard.instantiateViewController(withIdentifier: "Root") as! UITabBarController
    let navigationController = storyboard.instantiateViewController(withIdentifier: "Second") as! UINavigationController

    tabBarController.present(navigationController, animated: true) {

    }

    self.window = UIWindow.init(frame: UIScreen.main.bounds)
    self.window?.tintColor = UIColor(red: 0.0, green: 0.5, blue: 0.0, alpha: 1.0)
    self.window?.rootViewController = tabBarController
    self.window?.makeKeyAndVisible()

}

它工作得很好，但是我不能打开第二个ViewController，而第一个是出现的，第二个通知是被触发的:在控制台中：警告尝试显示ViewController.

Answer 1

用这个：

tabBarController.selectedIndex = 1

或者这个：

tabBarController.selectedViewController = tabBarController.viewControllers![1]

其中1可以是由tabBarController表示的任何viewcontrollers

Answer 2

我遇到了一个类似的问题，改变selectedIndex对我不起作用。根据项目的需求，您可以实例化ViewController并将其添加为Subview并移动到该Subview。完成后，请确保删除该Subview。

let replyView = self.storyboard?.instantiateViewControllerWithIdentifier("replyView")
    self.addChildViewController(replyView!)
    self.view.addSubview(replyView!.view)
    replyView!.didMoveToParentViewController(self)