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iOS

Posted by Raed Alahmari
Raed Alahmari
12,966 Points

Could not cast value of type 'nsnull' to 'nsstring'

I'm trying to retrieve images from firebase when I start the simulated it crash and I get this message " Could not cast value of type 'NSNull' (0x10eaf2378) to 'NSString' (0x10eee2b20). " this is my code

class ViewController: UIViewController {

@IBOutlet weak var gameName: UILabel! @IBOutlet weak var videoImage: UIImageView! @IBOutlet weak var uploadImage: UIButton!

var ref = Firebase(url:"https://xxx.firebaseio.com/images/") var imageRef = Firebase(url:"https://xxx.firebaseio.com/images/image/string") var base64String: NSString!

override func viewDidLoad() { super.viewDidLoad() // Do any additional setup after loading the view, typically from a nib.

imageRef.observeEventType(.Value, withBlock: { (snapshot) -> Void in
    self.base64String = snapshot.value as? String
    let decodeData = NSData(base64EncodedString: snapshot.value as! String, options: NSDataBase64DecodingOptions())
    let decodeImage = UIImage(data: decodeData!)
    self.videoImage.image = decodeImage
    print(self.base64String)
    }) { (error) -> Void in
        print(error.description)
}

}