Question

我使用Storyboards创建了我的项目。根ViewController位于Storyboard内，我没有在appDelegate中编写单个代码。

现在我想展示我的应用程序，所以我想将ViewController的根Tab Bar更改为我的TourVC，当应用程序的浏览完成后，我想再次切换将我的根ViewController提交给Tab Bar。

所以我在网上查阅并遵循以下几点

1）从app.plist文件中删除Storyboards， 2）取消选中＆＃34; isInitialViewController＆＃34;来自Storyboards，Tab Bar控制器检查它，因为它是根ViewController， 3）在appDelegate.m文件中添加此代码。

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;

但是我的应用程序崩溃了这个错误日志，

[ProductTourViewController selectedViewController]: unrecognized selector sent to instance 0x1766a9e0

我也收到警告，

Unsupported Configuration: Scene is unreachable due to lack of entry points and does not have an identifier for runtime access via -instantiateViewControllerWithIdentifier:.

Answer 1

目标-C：

UIStoryboard *storyboard = [UIStoryboard storyboardWithName:@"MainStoryboard" bundle:nil];
UITabBarController *rootViewController = [storyboard instantiateViewControllerWithIdentifier:@"tabBarcontroller"];
[[UIApplication sharedApplication].keyWindow setRootViewController:rootViewController];

斯威夫特：

 let mainStoryboard: UIStoryboard = UIStoryboard(name: "Main", bundle: nil)
 let viewController = mainStoryboard.instantiateViewControllerWithIdentifier("tabBarcontroller") as UITabBarController  
   UIApplication.sharedApplication().keyWindow?.rootViewController = viewController;

斯威夫特3：

let mainStoryboard: UIStoryboard = UIStoryboard(name: "Main", bundle: nil)
let viewController = mainStoryboard.instantiateViewController(withIdentifier: "tabBarcontroller") as! UITabBarController
UIApplication.shared.keyWindow?.rootViewController = viewController

Answer 2

enter image description here 在主故事板中为您的班级设置故事板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;

Answer 3

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

Answer 4

我用这个简单：

UIStoryboard *sb = [UIStoryboard storyboardWithName:@"NameOfStoryBoard" bundle:nil];
UITabBarController *rootViewController = [sb instantiateViewControllerWithIdentifier:@"NameOfTabBarController"];
[[UIApplication sharedApplication].keyWindow setRootViewController:rootViewController];

Answer 5

为了补充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

Answer 6

这是一篇旧文章，但我会答复。我不建议使用以下代码。

let mainStoryboard: UIStoryboard = UIStoryboard(name: "Main", bundle: nil)
let viewController = mainStoryboard.instantiateViewController(withIdentifier: "tabBarcontroller") as! UITabBarController
UIApplication.shared.keyWindow?.rootViewController = viewController

因为要创建两个实例。我建议在适当的ViewController中编写以下代码。

let appDelegate = UIApplication.shared.delegate as! AppDelegate
appDelegate.window?.rootViewController = self

Answer 7

Swift 3代码：

在didFinishLaunchingWithOptions Appdelegate函数中使用以下内容。替换＆＃34; HomeViewController＆＃34;使用ViewController，您希望在应用启动时设置为Root ViewController。

<TitledPane>
        <TextArea fx:id="taTop" wrapText="true" editable="false" prefHeight="100"/>
</TitledPane>
<TitledPane>
        <TableView fx:id="tableFrist" minHeight="120" maxHeight="120">
            <columns>
                <TableColumn fx:id="column" prefWidth="200"/>
            </columns>
        </TableView>
</TitledPane>
<ScrollPane AnchorPane.topAnchor="0.0" AnchorPane.rightAnchor="0.0" AnchorPane.bottomAnchor="0.0"
        AnchorPane.leftAnchor="0.0">
    <SplitPane orientation="VERTICAL" fx:id="splitPane">
        <TitledPane>
            <TreeTableView fx:id="tableSecond">
                <columns>
                    <TreeTableColumn fx:id="columnTreeS" prefWidth="200"/>
                </columns>
            </TreeTableView>
        </TitledPane>
        <TitledPane>
            <TreeTableView fx:id="tableThird">
                <columns>
                    <TreeTableColumn fx:id="columnTreeT" prefWidth="200"/>
                </columns>
            </TreeTableView>
        </TitledPane>
        <TitledPane>
            <TextArea fx:id="taBot" wrapText="true" editable="false"/>
        </TitledPane>
    </SplitPane>
</ScrollPane>

Answer 8

Swift 5 + Xcode 11：

像这样：

let viewController = mainStoryboard.instantiateViewController(withIdentifier: "tabBarcontroller") as! UITabBarController
UIApplication.shared.windows.first?.rootViewController = viewController
UIApplication.shared.windows.first?.makeKeyAndVisible()

或者像这样：

let viewController = mainStoryboard.instantiateViewController(withIdentifier: "tabBarcontroller") as! UITabBarController
self.view.window?.rootViewController = viewController
self.view.window?.makeKeyAndVisible()

两者都很好！

Answer 9

目标c

第1步：从info.plist中删除主要故事板

第2步：在界面构建器

中将故事板ID添加到视图控制器

步骤3：将以下代码添加到app delegate

中的应用程序完成方法

self.window = [[UIWindow alloc] initWithFrame: [UIScreen mainScreen].bounds];


//set main story board
if( condition){
    UIStoryboard *storyboard = [UIStoryboard storyboardWithName:@"StoryboardName1" bundle:nil];
    UIViewController *rootViewController = [storyboard instantiateViewControllerWithIdentifier:@"ViewController1"];
    [[UIApplication sharedApplication].keyWindow setRootViewController:rootViewController];
    [self window].rootViewController = rootViewController;
    [self.window makeKeyAndVisible];
}else{
    UIStoryboard *storyboard = [UIStoryboard storyboardWithName:@"StoryboardName2" bundle:nil];
    UIViewController *rootViewController = [storyboard instantiateViewControllerWithIdentifier:@"ViewController2"];
    [[UIApplication sharedApplication].keyWindow setRootViewController:rootViewController];
    [self window].rootViewController = rootViewController;
    [self.window makeKeyAndVisible];
}

以编程方式更改storyBoard的rootViewController

9 个答案: