How do I get collectionView to read my data response and count the array in another function swift?

var collectionView: UICollectionView?

var instanceOfCustomObject: CustomObject = CustomObject()

var accessToken: NSString!
var userDefaults: NSUserDefaults!

override func viewDidLoad() {
    super.viewDidLoad()

    userDefaults = NSUserDefaults.standardUserDefaults()
    self.accessToken = userDefaults!.objectForKey("accessToken") as NSString
    //        instanceOfCustomObject.someProperty = "Hello World"

    // Do any additional setup after loading the view, typically from a nib.
    let layout: UICollectionViewFlowLayout = UICollectionViewFlowLayout()
    layout.sectionInset = UIEdgeInsets(top: 20, left: 0, bottom: 0, right: 0)
    layout.itemSize = CGSize(width: 124, height: 124)
    layout.minimumInteritemSpacing = 1.0
    layout.minimumLineSpacing = 1.0
    collectionView = UICollectionView(frame: self.view.frame, collectionViewLayout: layout)
    collectionView!.dataSource = self
    collectionView!.delegate = self
    collectionView!.registerClass(Cell.self, forCellWithReuseIdentifier: "Cell")
    collectionView!.backgroundColor = UIColor.whiteColor()
    self.view.addSubview(collectionView!)

    getData()

}

func getData() -> Void {
    let baseUrl = NSURL(string:"https://api.instagram.com/v1/users/3/media/recent/?access_token=\(self.accessToken)")

    let forcastUrl = NSURL(string: "", relativeToURL: baseUrl)

    //        let data = NSData(contentsOfURL: forcastUrl)
    //        println(data)
    let sharedSession = NSURLSession.sharedSession()
    let downloadTask: NSURLSessionDownloadTask = sharedSession.downloadTaskWithURL(baseUrl, completionHandler: { (location: NSURL!, response: NSURLResponse!, error: NSError!) -> Void in


        //            var urlContents = NSString.stringWithContentsOfURL(location, encoding: NSUTF8StringEncoding, error: nil)
        //            println(urlContents)

        let dataObject = NSData(contentsOfURL: baseUrl)

        if (error == nil) {
            let responseDictionary: NSDictionary = NSJSONSerialization.JSONObjectWithData(dataObject, options: nil, error: nil) as NSDictionary

            var photos = responseDictionary.valueForKeyPath("data.images.standard_resolution.url") as NSArray
            println(photos)
            //                photoCount = self.photos!.count as Int

            dispatch_async(dispatch_get_main_queue(), { () -> Void in

                //                    self.temperatureLabel.text = "\(currentWeather.temperature)"
                //                    self.iconView.image = currentWeather.icon!
                //                    self.currentTimeLabel.text = "At \(currentWeather.currentTime!) it is"
                //                    self.humidityLabel.text = "\(currentWeather.humidity)"
                //                    self.percipitationLabel.text = "\(currentWeather.precipProbability)"
                //                    self.summeryLabel.text = "\(currentWeather.summary)"
                //
                //                    self.refreshActivityIndicator.stopAnimating()
                //                    self.refreshActivityIndicator.hidden = true
                //
                //                    self.refreshButton.hidden = false
            })

        } else {

            let networkIssueController = UIAlertController(title: "Error", message: "I got 99 problems but a bitch ain't one", preferredStyle: .ActionSheet)
            let okButton = UIAlertAction(title: "OK", style: .Default, handler: nil)
            networkIssueController.addAction(okButton)
            let cancelButton = UIAlertAction(title: "Cancel", style: .Cancel, handler: nil)
            networkIssueController.addAction(cancelButton)

            self.presentViewController(networkIssueController, animated: true, completion: nil)

            dispatch_async(dispatch_get_main_queue(), { () -> Void in
                //Stop refresh animation
                //                    self.refreshActivityIndicator.stopAnimating()
                //                    self.refreshActivityIndicator.hidden = true
                //                    self.refreshButton.hidden = false

            })
        }
    })

    downloadTask.resume()

}

override func didReceiveMemoryWarning() {
    super.didReceiveMemoryWarning()
    // Dispose of any resources that can be recreated.
}



func collectionView(collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {
    return photos.count
}

func collectionView(collectionView: UICollectionView, cellForItemAtIndexPath indexPath: NSIndexPath) -> UICollectionViewCell {
    let cell = collectionView.dequeueReusableCellWithReuseIdentifier("Cell", forIndexPath: indexPath) as Cell
    cell.textLabel.text = "Text"
    cell.imageView.image = UIImage(named: "star")
    return cell
}