Animation in AppDelegate of iOS App

Question

I have an animation in my AppDelegate. It is a mask, it is an animation similar to the Twitter launch animation. It zooms back and then forward to full screen. I do not have errors logged but I do not understand why I do not see the animation on the iOS Simulator or on an actual device.

This is my 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
    }


}

Answer 1

Have you try to use the view debugging tool of xcode6+? It can show you the full view hierarchy. I believe your imageView is behind the rootViewController's view.

So

1. assign the rootViewController
2. make the window key and visible
3. then add and animate your imageView

Answer 2

Did you try the following line:

self.window?.makeKeyAndVisible()

instead of

self.window = UIWindow(frame: UIScreen.mainScreen().bounds)

right at the top of your didFinishLaunchingWithOptions?

The call to UIWindow removes the initialized information especially if you used Storyboard to set up your initial launch screen etc. I ran into this issue with another project and the simple change did the trick. YMMV - good luck.