我在控制台得到以下错误:

应用程序在启动结束时应该有一个根视图控制器

下面是我的应用程序:didFinishLaunchWithOptions方法:

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {

    // Set Background Color/Pattern
    self.window.backgroundColor = [UIColor blackColor];
    self.tabBarController.tabBar.backgroundColor = [UIColor clearColor];
    //self.window.backgroundColor = [UIColor colorWithPatternImage:[UIImage imageNamed:@"testbg.png"]];

    // Set StatusBar Color
    [[UIApplication sharedApplication] setStatusBarStyle:UIStatusBarStyleBlackTranslucent];

    // Add the tab bar controller's current view as a subview of the window
    self.window.rootViewController = self.tabBarController;
    [self.window makeKeyAndVisible];
    return YES;
}

在Interface Builder中,UITabBarController的委托被连接到App委托。

有人知道怎么解决这个问题吗?


当前回答

没有一个答案能完全解决我的问题。

我正在开发一个升级到ARC的旧iOS4项目,现在正在为iOS 7开发Xcode 5

我通读了所有这些文件,并开始检查我的配置和代码。

为我修复它的是添加

-(BOOL) application:(UIApplication*) application didFinishLaunchingWithOptions: (NSDictionary*) launchOptions
{
    // Maybe do something
    return YES;
}

除了有

- (void)applicationDidFinishLaunching:(UIApplication *)application
{
}

我没有

-(BOOL) application:(UIApplication*) application didFinishLaunchingWithOptions: (NSDictionary*) launchOptions

在得到错误之前。

其他回答

当文件的主窗口所有者时也会出现此错误。Xib设置不正确。

文件的所有者是UIApplication->应用程序委托类的插入对象,窗口出口连接到窗口

这发生在我身上是因为我无意中注释了:

[self.window makeKeyAndVisible];

from

- (BOOL)application:(UIApplication*) didFinishLaunchingWithOptions:(NSDictionary*)

为了补充迈克弗林的答案,因为升级到Xcode 7和在iOS 9设备上运行我的应用程序,我添加了这个到我的(BOOL)应用程序:(UIApplication *)应用didFinishLaunchingWithOptions:(NSDictionary *)launchOptions

// Hide any window that isn't the main window
NSArray *windows = [[UIApplication sharedApplication] windows];
for (UIWindow *window in windows) {
    if (window != self.window) {
        window.hidden = YES;
    }
}

OrdoDei给出了一个正确而有价值的答案。我添加这个答案只是为了给出一个didFinishLaunchingWithOptions方法的例子,该方法使用了他的答案以及其他关于导航控制器的评论。

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

    // Override point for customization after application launch.

    // Instantiate the main menu view controller (UITableView with menu items).
    // Pass that view controller to the nav controller as the root of the nav stack.
    // This nav stack drives our *entire* app.
    UIViewController *viewController = [[XMMainMenuTableViewController alloc] init];
    self.navigationController = [[UINavigationController alloc] initWithRootViewController:viewController];

    // Instantiate the app's window. Then get the nav controller's view into that window, and onto the screen.
    self.window = [[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]];
    // [self.window addSubview:self.navigationController.view];
    // The disabled line above was replaced by line below. Fixed Apple's complaint in log: Application windows are expected to have a root view controller at the end of application launch
    [self.window setRootViewController:self.navigationController];
    self.window.backgroundColor = [UIColor whiteColor];
    [self.window makeKeyAndVisible];
    return YES;
}

在使用XCode 4.6.3和iOS 6.1将我的UI替换为Storyboard后收到相同的错误

通过清除AppDelegate中的didFinishLaucnhingWithOptions中的所有代码来解决这个问题

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
    return YES;
}