无法识别的应用程序中的选择器didFinishLaunchingWithOptions与topViewController分配

Question

这是什么原因造成的？我在Xcode 4.3上运行iOS 5.1并使用Storyboard。

'NSInvalidArgumentException', reason: '-[WFTopTableViewController topViewController]: unrecognized selector sent to instance 0x6d56f80' 


- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions 
{ 
    // Initial view controller is a Table View Controller, so we look up the window's rootViewController. 
    UINavigationController *navigationController = (UINavigationController *)self.window.rootViewController; 
    // Set up the controller. 
    WFTopTableViewController *controller = (WFTopTableViewController *)navigationController.topViewController; 
    // Pass the controller the managed object context for the first time. 
    controller.managedObjectContext = self.managedObjectContext; 
    return YES; 
} 

谢谢！ 阿曼达

Answer 1

试试这个：

(BOOL)application:(UIApplication*)application didFinishLaunchingWithOptions:(NSDictionary*)launchOptions { 
    WFTopTableViewController *controller = (WFTopTableViewController*)self.window.rootViewController; 
    controller.managedObjectContext = self.managedObjectContext; 
    return YES; 
} 

你的窗口的RootViewController的已经是WFTopTableViewController，不是一个UINavigationController。如果您需要，请确保在Interface Builder中为UINavigationController选择'Is Initial View Controller'选项。