以编程方式更改storyBoard的rootViewController
我用Storyboards创build了我的项目。 根ViewController位于Storyboard ，我没有在appDelegate编写单个代码。
现在，我想显示我的应用程序的一个浏览，所以我想要从根目录Tab Bar更改根视图控制器到我的TourVC，当应用程序的巡视完成后，我想再次切换回我的根视图控制器到Tab Bar 。
所以我在网上查了一下，跟着以下几点
1）从app.plist文件中删除Storyboards ，2）取消选中Storyboards选项“isInitialViewController”，在Tab Bar控制器的情况下检查，因为它的根ViewController ，3）将此代码添加到appDelegate.m文件中。
self.window = [[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]]; ProductTourViewController *PT = [[ProductTourViewController alloc] initWithNibName:@"ProductTourViewController" bundle:nil]; self.window.rootViewController = PT; [self.window makeKeyAndVisible]; return YES;
但我的应用程序崩溃与此错误日志，
[ProductTourViewController selectedViewController]: unrecognized selector sent to instance 0x1766a9e0
我还得到一个警告，
Unsupported Configuration: Scene is unreachable due to lack of entry points and does not have an identifier for runtime access via -instantiateViewControllerWithIdentifier:.
Objective-C的：
UIStoryboard *storyboard = [UIStoryboard storyboardWithName:@"MainStoryboard" bundle:nil]; UITabBarController *rootViewController = [storyboard instantiateViewControllerWithIdentifier:@"tabBarcontroller"]; [[UIApplication sharedApplication].keyWindow setRootViewController:rootViewController];
Swift：
let mainStoryboard: UIStoryboard = UIStoryboard(name: "Main", bundle: nil) let viewController = mainStoryboard.instantiateViewControllerWithIdentifier("tabBarcontroller") as UITabBarController UIApplication.sharedApplication().keyWindow?.rootViewController = viewController;
Swift 3：
let mainStoryboard: UIStoryboard = UIStoryboard(name: "Main", bundle: nil) let viewController = mainStoryboard.instantiateViewController(withIdentifier: "tabBarcontroller") as! UITabBarController UIApplication.shared.keyWindow?.rootViewController = viewController
在您的主故事板中为您的课程设置故事板ID。
UIStoryboard *MainStoryboard = [UIStoryboard storyboardWithName:@"Main" bundle: nil]; UINavigationController *controller = (UINavigationController*)[MainStoryboard instantiateViewControllerWithIdentifier: @"RootNavigationController"]; LoginViewController *login=[MainStoryboard instantiateViewControllerWithIdentifier:@"LoginViewController"]; [controller setViewControllers:[NSArray arrayWithObject:login] animated:YES]; self.window.rootViewController=controller;
在swift中我们可以实现它如下
let storyboard = UIStoryboard(name: "StartingPage", bundle: NSBundle.mainBundle()) let loginView: SignInVC = storyboard.instantiateViewControllerWithIdentifier("SignInVC") as! SignInVC UIApplication.sharedApplication().keyWindow?.rootViewController = loginView
我使用简单的这个：
UIStoryboard *sb = [UIStoryboard storyboardWithName:@"NameOfStoryBoard" bundle:nil]; UITabBarController *rootViewController = [sb instantiateViewControllerWithIdentifier:@"NameOfTabBarController"]; [[UIApplication sharedApplication].keyWindow setRootViewController:rootViewController];
为了增加Sunny Shah的答案，这是它的Swift 3版本：
let mainStoryBoard: UIStoryboard = UIStoryboard(name: "Main", bundle: nil) let viewController: UIViewController = mainStoryBoard.instantiateViewController(withIdentifier: "MainTabBarController") as! UITabBarController UIApplication.shared.keyWindow?.rootViewController = viewController
Swift 3代码：
在下面的didFinishLaunchingWithOptions Appdelegate函数中使用。 将“HomeViewController”replace为您想在应用启动时设置为Root ViewController的ViewController。
self.window = UIWindow(frame: UIScreen.main.bounds) let storyboard = UIStoryboard(name: "Main", bundle: nil) let initialViewController = storyboard.instantiateViewController(withIdentifier: "HomeViewController") self.window?.rootViewController = initialViewController self.window?.makeKeyAndVisible() return true