选择要首先打开的视图控制器，然后转到属性检查器。 转到初始场景，检查初始视图控制器选项。

这是你的初始视图控制器在应用启动时首先打开。

打开mainstoryboard，首先选择要启动的视图，然后打开Utilities—> Attributes。在“视图控制器”下面，你会看到“Is initial View Controller”单选按钮。选择它。

——对修改后的问题:

也许你可以试试这个:在你的初始视图的ViewDidLoad部分写一个方法，当这个方法在应用程序启动时运行，方法触发一个到另一个视图的segue。

我认为这是不可能的。 相反，你可以有一个初始控制器它有segue到不同的视图控制器。在启动时，您可以决定以编程方式执行哪个segue。

如何没有一个虚拟的初始视图控制器

确保所有初始视图控制器都有一个故事板ID。

在故事板中，取消选中第一个视图控制器的“Is initial View Controller”属性。

如果你在这个时候运行你的应用，你会看到:

失败的实例化默认视图控制器UIMainStoryboardFile 'MainStoryboard' -也许指定的入口点没有设置?

你会注意到你在app委托中的window属性现在是nil。

在应用程序的设置中，转到目标和信息选项卡。这里清除了主线故事板文件基本名称的值。在“常规”页签中，清除“主界面”的值。这将删除警告。

在应用委托的应用程序中创建窗口和所需的初始视图控制器:

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
    self.window = [[UIWindow alloc] initWithFrame:UIScreen.mainScreen.bounds];

    UIStoryboard *storyboard = [UIStoryboard storyboardWithName:@"MainStoryboard" bundle:nil];

    UIViewController *viewController = // determine the initial view controller here and instantiate it with [storyboard instantiateViewControllerWithIdentifier:<storyboard id>];

    self.window.rootViewController = viewController;
    [self.window makeKeyAndVisible];

    return YES;
}

(UIApplication *)application willFinishLaunchingWithOptions:(NSDictionary *)launchOptions你可以通过编程方式设置(BOOL)应用程序中的关键窗口的rootViewController

例如:

- (BOOL)application:(UIApplication *)application willFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
    if (shouldShowAnotherViewControllerAsRoot) {
        UIStoryboard *storyboard = self.window.rootViewController.storyboard;
        UIViewController *rootViewController = [storyboard instantiateViewControllerWithIdentifier:@"rootNavigationController"];
        self.window.rootViewController = rootViewController;
        [self.window makeKeyAndVisible];
    }

    return YES;
}

几天前我也遇到了同样的情况。一个非常简单的技巧解决了这个问题。 我设置在launch2之前隐藏我的初始视图控制器。如果初始视图控制器是正确的控制器，它在viewDidLoad中被设置为可见。否则，执行一个segue到所需的视图控制器。它在iOS 6.1及以上版本运行良好。我确信它适用于早期版本的iOS。

对于所有喜欢霉霉的人，下面是@Travis用Swift翻译的答案:

做@Travis在Objective C代码之前解释的事情。然后,

func application(application: UIApplication, didFinishLaunchingWithOptions launchOptions: [NSObject: AnyObject]?) -> Bool {

    self.window = UIWindow(frame: UIScreen.mainScreen().bounds)
    let mainStoryboard: UIStoryboard = UIStoryboard(name: "Main", bundle: nil)
    var exampleViewController: ExampleViewController = mainStoryboard.instantiateViewControllerWithIdentifier("ExampleController") as! ExampleViewController

    self.window?.rootViewController = exampleViewController

    self.window?.makeKeyAndVisible()

    return true
}

ExampleViewController将是您想要显示的新的初始视图控制器。

步骤解释如下:

创建一个与当前窗口大小相同的新窗口，并将其设置为主窗口 实例化一个故事板，我们可以用它来创建新的初始视图控制器 基于Storyboard ID实例化我们新的初始视图控制器 将新窗口的根视图控制器设置为我们刚刚启动的新控制器 使新窗口可见

享受和快乐的编程!

你可以将Navigation rootviewcontroller设置为一个主视图控制器。 这个想法可以用于根据应用程序需求自动登录。

UIStoryboard *mainStoryboard = [UIStoryboard storyboardWithName:@"Main" bundle: nil];

UIViewController viewController = (HomeController*)[mainStoryboard instantiateViewControllerWithIdentifier: @"HomeController"];

UINavigationController navController = [[UINavigationController alloc] initWithRootViewController:viewController];

 self.window.rootViewController = navController;

if (NSFoundationVersionNumber > NSFoundationVersionNumber_iOS_6_1) {

    // do stuff for iOS 7 and newer

    navController.navigationBar.barTintColor = [UIColor colorWithRed:88/255.0 green:164/255.0 blue:73/255.0 alpha:1.0];

    navController.navigationItem.leftBarButtonItem.tintColor = [UIColor colorWithRed:88/255.0 green:164/255.0 blue:73/255.0 alpha:1.0];

    navController.navigationBar.tintColor = [UIColor whiteColor];

    navController.navigationItem.titleView.tintColor = [UIColor whiteColor];

    NSDictionary *titleAttributes =@{

                                     NSFontAttributeName :[UIFont fontWithName:@"Helvetica-Bold" size:14.0],

                                     NSForegroundColorAttributeName : [UIColor whiteColor]

                                     };

    navController.navigationBar.titleTextAttributes = titleAttributes;

    [[UIApplication sharedApplication] setStatusBarStyle:UIStatusBarStyleLightContent];

}

else {

    // do stuff for older versions than iOS 7

    navController.navigationBar.tintColor = [UIColor colorWithRed:88/255.0 green:164/255.0 blue:73/255.0 alpha:1.0];



    navController.navigationItem.titleView.tintColor = [UIColor whiteColor];

}

[self.window makeKeyAndVisible];

对于StoryboardSegue用户

UIStoryboard *mainStoryboard = [UIStoryboard storyboardWithName:@"Main" bundle: nil];

// Go to Login Screen of story board with Identifier name : LoginViewController_Identifier

LoginViewController *loginViewController = (LoginViewController*)[mainStoryboard instantiateViewControllerWithIdentifier:@“LoginViewController_Identifier”];

navigationController = [[UINavigationController alloc] initWithRootViewController:testViewController];

self.window.rootViewController = navigationController;

[self.window makeKeyAndVisible];

// Go To Main screen if you are already Logged In Just check your saving credential here

if([SavedpreferenceForLogin] > 0){
    [loginViewController performSegueWithIdentifier:@"mainview_action" sender:nil];
}

谢谢

您可以使用接口生成器以及编程方式设置初始视图控制器。

下面是编程使用的方法。

objective - c:

        self.window = [[UIWindow alloc] initWithFrame:UIScreen.mainScreen.bounds];
        UIStoryboard *storyboard = [UIStoryboard storyboardWithName:@"MainStoryboard" bundle:nil];

        UIViewController *viewController = [storyboard instantiateViewControllerWithIdentifier:@"HomeViewController"]; // <storyboard id>

        self.window.rootViewController = viewController;
        [self.window makeKeyAndVisible];

        return YES;

迅速:

        self.window = UIWindow(frame: UIScreen.mainScreen().bounds)
        let mainStoryboard: UIStoryboard = UIStoryboard(name: "Main", bundle: nil)

        var objMainViewController: MainViewController = mainStoryboard.instantiateViewControllerWithIdentifier("MainController") as! MainViewController

        self.window?.rootViewController = objMainViewController

        self.window?.makeKeyAndVisible()

        return true

谢谢在AppDelegate中修改如下:

func application(application: UIApplication, didFinishLaunchingWithOptions launchOptions: [NSObject: AnyObject]?) ->     Bool {
//Some code to check value of pins

if pins! == "Verified"{
        print(pins)
        self.window = UIWindow(frame: UIScreen.mainScreen().bounds)
        let mainStoryboard: UIStoryboard = UIStoryboard(name: "HomePage", bundle: nil)
        let exampleViewController: UINavigationController = mainStoryboard.instantiateViewControllerWithIdentifier("SBHP") as! UINavigationController

        self.window?.rootViewController = exampleViewController

        self.window?.makeKeyAndVisible()
    }else{
        print(pins)
        self.window = UIWindow(frame: UIScreen.mainScreen().bounds)
        let mainStoryboard: UIStoryboard = UIStoryboard(name: "Main", bundle: nil)
        let exampleViewController: UINavigationController = mainStoryboard.instantiateViewControllerWithIdentifier("SBUser") as! UINavigationController

        self.window?.rootViewController = exampleViewController

        self.window?.makeKeyAndVisible()
    }

找到了简单的解决方案-不需要从故事板和编辑项目信息选项卡中删除“初始视图控制器检查”，并使用makeKeyAndVisible，只是放置

self.window.rootViewController = rootVC;

in

- (BOOL) application:didFinishLaunchingWithOptions:

Swift 3:更新到@victor-sigler的代码

func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplicationLaunchOptionsKey: Any]?) -> Bool {
    self.window = UIWindow(frame: UIScreen.main.bounds)

    // Assuming your storyboard is named "Main"
    let mainStoryboard: UIStoryboard = UIStoryboard(name: "Main", bundle: nil)

    // Add code here (e.g. if/else) to determine which view controller class (chooseViewControllerA or chooseViewControllerB) and storyboard ID (chooseStoryboardA or chooseStoryboardB) to send the user to

    if(condition){
        let initialViewController: chooseViewControllerA = mainStoryboard.instantiateViewController(withIdentifier: "chooseStoryboardA") as! chooseViewControllerA
        self.window?.rootViewController = initialViewController
    )
    }else{
        let initialViewController: chooseViewControllerB = mainStoryboard.instantiateViewController(withIdentifier: "chooseStoryboardB") as! chooseViewControllerB
        self.window?.rootViewController = initialViewController
    )

    self.window?.makeKeyAndVisible(

    return true
}

在AppDelegate.swift中，你可以添加以下代码:

let sb = UIStoryboard(name: "Main", bundle: nil)
let vc = sb.instantiateViewController(withIdentifier: "YourViewController_StorboardID")
self.window?.rootViewController = vc
self.window?.makeKeyAndVisible()

当然，你需要实现你的逻辑，基于什么标准你将选择一个合适的视图控制器。

另外，不要忘记添加一个标识(select storyboard -> Controller Scene -> Show the identity inspector -> assign StorboardID)。

我创建了一个路由类来处理动态导航和保持干净的AppDelegate类，我希望它也能帮助其他。

//
//  Routing.swift
// 
//
//  Created by Varun Naharia on 02/02/17.
//  Copyright © 2017 TechNaharia. All rights reserved.
//

import Foundation
import UIKit
import CoreLocation

class Routing {

    class func decideInitialViewController(window:UIWindow){
        let userDefaults = UserDefaults.standard
        if((Routing.getUserDefault("isFirstRun")) == nil)
        {
            Routing.setAnimatedAsInitialViewContoller(window: window)
        }
        else if((userDefaults.object(forKey: "User")) != nil)
        {
            Routing.setHomeAsInitialViewContoller(window: window)
        }
        else
        {
            Routing.setLoginAsInitialViewContoller(window: window)
        }

    }

    class func setAnimatedAsInitialViewContoller(window:UIWindow) {
        Routing.setUserDefault("Yes", KeyToSave: "isFirstRun")
        let mainStoryboard: UIStoryboard = UIStoryboard(name: "Main", bundle: nil)
        let animatedViewController: AnimatedViewController = mainStoryboard.instantiateViewController(withIdentifier: "AnimatedViewController") as! AnimatedViewController

        window.rootViewController = animatedViewController
        window.makeKeyAndVisible()
    }

    class func setHomeAsInitialViewContoller(window:UIWindow) {
        let userDefaults = UserDefaults.standard
        let decoded  = userDefaults.object(forKey: "User") as! Data
        User.currentUser = NSKeyedUnarchiver.unarchiveObject(with: decoded) as! User

        if(User.currentUser.userId != nil && User.currentUser.userId != "")
        {
            let mainStoryboard: UIStoryboard = UIStoryboard(name: "Main", bundle: nil)
            let homeViewController: HomeViewController = mainStoryboard.instantiateViewController(withIdentifier: "HomeViewController") as! HomeViewController
            let loginViewController: UINavigationController = mainStoryboard.instantiateViewController(withIdentifier: "LoginNavigationViewController") as! UINavigationController
            loginViewController.viewControllers.append(homeViewController)
            window.rootViewController = loginViewController
        }
        window.makeKeyAndVisible()
    }

    class func setLoginAsInitialViewContoller(window:UIWindow) {
        let mainStoryboard: UIStoryboard = UIStoryboard(name: "Main", bundle: nil)
        let loginViewController: UINavigationController = mainStoryboard.instantiateViewController(withIdentifier: "LoginNavigationViewController") as! UINavigationController

        window.rootViewController = loginViewController
        window.makeKeyAndVisible()
    }

  class func setUserDefault(_ ObjectToSave : Any?  , KeyToSave : String)
    {
        let defaults = UserDefaults.standard

        if (ObjectToSave != nil)
        {

            defaults.set(ObjectToSave, forKey: KeyToSave)
        }

        UserDefaults.standard.synchronize()
    }

    class func getUserDefault(_ KeyToReturnValye : String) -> Any?
    {
        let defaults = UserDefaults.standard

        if let name = defaults.value(forKey: KeyToReturnValye)
        {
            return name as Any
        }
        return nil
    }

    class func removetUserDefault(_ KeyToRemove : String)
    {
        let defaults = UserDefaults.standard
        defaults.removeObject(forKey: KeyToRemove)
        UserDefaults.standard.synchronize()
    }

}

在AppDelegate中调用这个

 self.window = UIWindow(frame: UIScreen.main.bounds)
 Routing.decideInitialViewController(window: self.window!)

使用Swift 3和Swift 4避免强制铸造的另一个解决方案是这样的

func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplicationLaunchOptionsKey: Any]?) -> Bool {
    self.window = UIWindow(frame: UIScreen.main.bounds)
    let storyboard = UIStoryboard(name: "Main", bundle: nil)
    guard let viewController = storyboard.instantiateViewController(withIdentifier: "YourViewController") as? YourViewController else {
        return false
    }
    self.window?.rootViewController = viewController
    self.window?.makeKeyAndVisible()
    return true
}

下面是使用UINavigationController

func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplicationLaunchOptionsKey: Any]?) -> Bool {
    self.window = UIWindow(frame: UIScreen.main.bounds)
    let storyboard = UIStoryboard(name: "Main", bundle: nil)
    guard let viewController = storyboard.instantiateViewController(withIdentifier: "YourViewController") as? YourViewController else {
        return false
    }
    let navigationController = UINavigationController(rootViewController: viewController)
    self.window?.rootViewController = navigationController
    self.window?.makeKeyAndVisible()
    return true
}

let mainStoryboard = UIStoryboard(name: "Main", bundle: nil)
let vc = mainStoryboard.instantiateViewController(withIdentifier: "storyBoardid") as! ViewController
let navigationController = UINavigationController(rootViewController: vc)
UIApplication.shared.delegate.window?.rootViewController = navigationController

另一种方法是present viewController，

let mainStoryboard = UIStoryboard(name: "Main", bundle: nil)
let vc = mainStoryboard.instantiateViewController(withIdentifier: "storyBoardid") as! ViewController
self.present(vc,animated:true,completion:nil)

首先你需要创建storyboard的对象然后改变根(如果需要)然后你引用特定的视图控制器它会被推送当前视图控制器(如果你改变根)否则它会呈现新的视图控制器

Swift 4, Xcode 9

在AppDelegate.swift文件中

func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplicationLaunchOptionsKey: Any]?) -> Bool {
    let storyboard = UIStoryboard(name: "Main", bundle: nil)
    let firstVC = storyboard.instantiateViewController(withIdentifier: "firstViewController") as! firstViewController
    self.window?.rootViewController = firstVC
}

 func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplicationLaunchOptionsKey: Any]?) -> Bool {
        self.window = UIWindow(frame: UIScreen.main.bounds)
        let storyboard = UIStoryboard(name: "Main", bundle: nil)
        if (PreferenceHelper.getAccessToken() != "") {
            let initialViewController = storyboard.instantiateViewController(withIdentifier: "your View Controller Identifier")
            self.window?.rootViewController = initialViewController
        } else {
            let initialViewController = storyboard.instantiateViewController(withIdentifier: "your View Controller identifier")
            self.window?.rootViewController = initialViewController
        }
        self.window?.makeKeyAndVisible()
        return true
    }

/*
use your view Controller identifier must use it doubles quotes**strong text**

Swift 5或以上版本#创建路由视图控制器 如果你使用xcode 11或以上版本，首先初始化var window: UIWindow?在AppDelegate

let rootVC = mainStoryboard.instantiateViewController(withIdentifier: "YOURCONTROLLER") as! YOURCONTROLLER

        navigationController.setNavigationBarHidden(true, animated: true)
        UIApplication.shared.windows.first?.rootViewController = UINavigationController.init(rootViewController: rootVC)
        UIApplication.shared.windows.first?.makeKeyAndVisible()

斯威夫特5

如果你没有一个ViewController设置为storyboard中的初始ViewController，你需要做两件事:

进入你的项目TARGETS，选择你的项目-> General ->清除Main Interface字段。 总是在项目TARGETS中，现在转到Info ->应用场景清单->场景配置->应用程序会话角色-> Item0(默认配置)->删除故事板名称字段。

最后，你现在可以在SceneDelegate中添加你的代码:

func scene(_ scene: UIScene, willConnectTo session: UISceneSession, options connectionOptions: UIScene.ConnectionOptions) {
    // Use this method to optionally configure and attach the UIWindow `window` to the provided UIWindowScene `scene`.
    // If using a storyboard, the `window` property will automatically be initialized and attached to the scene.
    // This delegate does not imply the connecting scene or session are new (see `application:configurationForConnectingSceneSession` instead).
    guard let windowScene = (scene as? UIWindowScene) else { return }

    window = UIWindow(windowScene: windowScene)


    let storyboard = UIStoryboard(name: "Main", bundle: nil)
    // Make sure you set an Storyboard ID for the view controller you want to instantiate
    window?.rootViewController = storyboard.instantiateViewController(withIdentifier: identifier)
    window?.makeKeyAndVisible()

}

如果你在iOS 13+中使用场景委托:

在你的信息中确认。Plist文件你发现行在:

Application Scene Manifest > Scene Configuration > Application Session Role > Item 0

并在那里删除对Main Storyboard的引用。否则，您将得到关于从storyboard实例化失败的相同警告。

同样，将代码从应用程序委托移动到场景委托方法scene(_:willConnectTo:options:)，因为这是现在处理生命周期事件的地方。

如果你不想改变applicationDidFinish，你可以做下面的技巧:

设置导航控制器为初始视图控制器，并分配给它一个自定义类'MyNavigationController'。然后你可以在viewDidLoad期间调整它的根视图控制器——它会覆盖你在故事板中设置的根视图控制器。

class MyNavigationController: UINavigationController {
    override func viewDidLoad() {
        super.viewDidLoad()
        if !isLoggedIn() {
            viewControllers = [R.storyboard.authentication.loginView()!]
        }
    }

    private func isLoggedIn() -> Bool {
        return false
    }

}

Xcode 12.4 Swift 5

在SceneDelegate.Swift

func scene(_ scene: UIScene, willConnectTo session: UISceneSession, options connectionOptions: UIScene.ConnectionOptions) {
    guard let windowScene = (scene as? UIWindowScene) else { return }
    let window = UIWindow(windowScene: windowScene)
    let storyboard = UIStoryboard(name: "Main", bundle: nil)
    window.rootViewController = storyboard.instantiateViewController(withIdentifier: "UserViewController") as! UserViewController
    
    self.window = window
    window.makeKeyAndVisible()
}

你可以添加视图控制器场景将要显示的条件

使用storyboard(而不是Main)设置初始ViewController

[Swift 5和Xcode 11]

主要。>属性检查器->取消勾选初始视图控制器 应用程序目标->通用->删除所有从主界面 编辑App委托

@main
class AppDelegate: UIResponder, UIApplicationDelegate {
    
    var window: UIWindow?

    func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?) -> Bool {
        // Override point for customization after application launch.
        self.window = UIWindow(frame: UIScreen.main.bounds)
        
        let storyboard: UIStoryboard = UIStoryboard(name: "SomeStoryboard", bundle: nil) //SomeStoryboard  is name of .storyboard
        let viewController: ViewController = storyboard.instantiateViewController(withIdentifier: "someStoryboardId") as! ViewController //someStoryboardId is Storyboard ID

        self.window?.rootViewController = viewController
        self.window?.makeKeyAndVisible()

        return true
    }
}