在AppDelegate動畫後不顯示HomeViewController

Question

我試圖在啓動應用程序時在AppDelegate中執行動畫。 （從本教程：http://iosdevtips.co/post/88481653818/twitter-ios-app-bird-zoom-animation）

，我想就我的HomeViewController面具

這是我的AppDelegate

import UIKit 
import QuartzCore 

@UIApplicationMain 

class AppDelegate: UIResponder, UIApplicationDelegate { 

var window: UIWindow? 
var mask: CALayer? 
var imageView: UIImageView? 


func application(application: UIApplication, didFinishLaunchingWithOptions launchOptions: [NSObject: AnyObject]?) -> Bool { 
    // Override point for customization after application launch. 
    self.window = UIWindow(frame: UIScreen.mainScreen().bounds) 

    let imageView = UIImageView(frame: self.window!.frame) 
    imageView.image = UIImage(named: "portfolioscreen") 
    self.window!.addSubview(imageView) 

    self.mask = CALayer() 
    self.mask!.contents = UIImage(named: "BearLogo.png")!.CGImage 
    self.mask!.contentsGravity = kCAGravityResizeAspect 
    self.mask!.bounds = CGRect(x: 0, y: 0, width: 100, height: 100) 
    self.mask!.anchorPoint = CGPoint(x: 0.5, y: 0.5) 
    self.mask!.position = CGPoint(x: imageView.frame.size.width/2, y: imageView.frame.size.height/2) 
    imageView.layer.mask = mask 
    self.imageView = imageView 

    animateMask() 

    if(NSUserDefaults.standardUserDefaults().integerForKey("visits") > 0) 
    { 
     var navigationController = UINavigationController(rootViewController: HomeViewController()) 
     window?.rootViewController = navigationController 
    } 
    else 
    { 
     window?.rootViewController = ViewController() 
     NSUserDefaults.standardUserDefaults().setInteger(1, forKey: "visits") 
    } 
    //window?.makeKeyAndVisible() 

    self.window!.backgroundColor = UIColor(red: 70/255, green: 154/255, blue: 233/255, alpha: 1) 
    self.window!.makeKeyAndVisible() 
    UIApplication.sharedApplication().statusBarHidden = true 
    return true 

} 


func applicationWillResignActive(application: UIApplication) { 
    // Sent when the application is about to move from active to inactive state. This can occur for certain types of temporary interruptions (such as an incoming phone call or SMS message) or when the user quits the application and it begins the transition to the background state. 
    // Use this method to pause ongoing tasks, disable timers, and throttle down OpenGL ES frame rates. Games should use this method to pause the game. 
} 

func applicationDidEnterBackground(application: UIApplication) { 
    // Use this method to release shared resources, save user data, invalidate timers, and store enough application state information to restore your application to its current state in case it is terminated later. 
    // If your application supports background execution, this method is called instead of applicationWillTerminate: when the user quits. 
} 

func applicationWillEnterForeground(application: UIApplication) { 
    // Called as part of the transition from the background to the inactive state; here you can undo many of the changes made on entering the background. 
} 

func applicationDidBecomeActive(application: UIApplication) { 
    // Restart any tasks that were paused (or not yet started) while the application was inactive. If the application was previously in the background, optionally refresh the user interface. 
} 

func applicationWillTerminate(application: UIApplication) { 
    // Called when the application is about to terminate. Save data if appropriate. See also applicationDidEnterBackground:. 
} 

func animateMask() { 
    let keyFrameAnimation = CAKeyframeAnimation(keyPath: "bounds") 
    keyFrameAnimation.delegate = self 
    keyFrameAnimation.duration = 1 
    keyFrameAnimation.beginTime = CACurrentMediaTime() + 1 //add delay of 1 second 
    let initalBounds = NSValue(CGRect: mask!.bounds) 
    let secondBounds = NSValue(CGRect: CGRect(x: 0, y: 0, width: 90, height: 90)) 
    let finalBounds = NSValue(CGRect: CGRect(x: 0, y: 0, width: 1500, height: 1500)) 
    keyFrameAnimation.values = [initalBounds, secondBounds, finalBounds] 
    keyFrameAnimation.keyTimes = [0, 0.3, 1] 
    keyFrameAnimation.timingFunctions = [CAMediaTimingFunction(name: kCAMediaTimingFunctionEaseInEaseOut), CAMediaTimingFunction(name: kCAMediaTimingFunctionEaseOut)] 
    self.mask!.addAnimation(keyFrameAnimation, forKey: "bounds") 
} 

override func animationDidStop(anim: CAAnimation!, finished flag: Bool) { 
    self.imageView!.layer.mask = nil //remove mask when animation completes 

    var homeViewController = HomeViewController(nibName: "HomeViewController", bundle: NSBundle.mainBundle()) 

    self.window?.rootViewController = homeViewController 
    self.window!.makeKeyAndVisible() 



} 


} 

當我開始崩潰模擬器，並在底部有錯誤右上角。我寫錯了？

幫助將不勝感激

Answer 1

請把執行此塊在completionHandler在 動畫的方法和嘗試？

if(NSUserDefaults.standardUserDefaults().integerForKey("visits") > 0) 
    { 
     var navigationController = UINavigationController(rootViewController: HomeViewController()) 
     window?.rootViewController = navigationController 
    } 
    else 
    { 
     window?.rootViewController = ViewController() 
     NSUserDefaults.standardUserDefaults().setInteger(1, forKey: "visits") 
    }