昨晚它还在工作，但是当我运行我的代码时，现在我收到了：
致命错误：在展开可选值时意外发现 nil。
有人可以帮我找到这个错误吗？
import UIKit
class UserRegistration: UIViewController, UINavigationControllerDelegate, UIImagePickerControllerDelegate, UITextFieldDelegate {
//USER REGISTRATION FORM
//Activity Indicator
var activityIndicator: UIActivityIndicatorView = UIActivityIndicatorView()
//Error
func displayAlert(title:String, error:String){
//create Alert
var alert = UIAlertController(title: title, message: error, preferredStyle: UIAlertControllerStyle.Alert)
alert.addAction(UIAlertAction(title: "Ok", style: .Cancel, handler: nil))
self.presentViewController(alert, animated: true, completion: nil)
}
//User Profile Picture Selection
var profileImage = UIImage()
var isThereImage = false
@IBOutlet var uploadProfilePictureButton: UIButton!
@IBAction func uploadProfilePicture(sender: AnyObject) {
//Settings needed for image upload
var image = UIImagePickerController()
image.delegate = self
image.sourceType = UIImagePickerControllerSourceType.PhotoLibrary //can use '.camera' to access camera
image.allowsEditing = true
//Select image. FYI Completion is a function that happens when viewcontroller is presented
self.presentViewController(image, animated: true, completion: nil)
}
func imagePickerController(picker: UIImagePickerController!, didFinishPickingImage image: UIImage!, editingInfo: [NSObject : AnyObject]!) {
//Store image in local variable to be resized later
profileImage = image
println("Image is selected")
//Manually Close View Controller
self.dismissViewControllerAnimated(true, completion: nil)
//Remove button title
uploadProfilePictureButton.setTitle("", forState: .Normal)
//Display Image
uploadProfilePictureButton.setBackgroundImage(image, forState: .Normal)
//Set isThereImage Boolean
isThereImage = true
}
//---------------------------------------
//User Input Information
@IBOutlet var userEmailAddress: UITextField!
@IBOutlet var userPasswordOne: UITextField!
@IBOutlet var userPasswordTwo: UITextField!
@IBOutlet var passwordConfirmationMatch: UILabel!
var confirmedPassword = Bool()
//---------------------------------------
//Submit User Input to Database
@IBAction func userRegistration(sender: AnyObject) {
var error = ""
//Verify if User Exist and Passwords Match
if userEmailAddress.text == "" || userPasswordOne.text == "" || confirmedPassword == false {
error = "Please enter an email address and password, or make sure your passwords match."
println("Registration had an error")
}
if error != "" {
displayAlert("Error in Registration", error: error)
} else {
//Sign Up User
var user = PFUser()
//Resize Profile Picture
let size = CGSizeApplyAffineTransform(profileImage.size, CGAffineTransformMakeScale(0.5, 0.5))
let hasAlpha = true
let scale: CGFloat = 0.0 // Automatically use scale factor of main screen
UIGraphicsBeginImageContextWithOptions(size, !hasAlpha, scale)
profileImage.drawInRect(CGRect(origin: CGPointZero, size: size))
let scaledImage = UIGraphicsGetImageFromCurrentImageContext()
UIGraphicsEndImageContext()
//User Information
user.password = userPasswordTwo.text
user.email = userEmailAddress.text
user.username = userEmailAddress.text
if isThereImage == false {
displayAlert("Please upload a picture for your profile.", error: error)
}else if isThereImage == true {
var imageData = UIImagePNGRepresentation(scaledImage)
var imageFile = PFFile(name: userEmailAddress.text + ".png", data:imageData)
user.setObject(imageFile, forKey: "userProfileImage")
}
user.setObject("", forKey: "firstName")
user.setObject("", forKey: "lastName")
user.setObject("", forKey: "userLocation")
//Insert Activity Indicator here
activityIndicator = UIActivityIndicatorView(frame: CGRectMake(0, 0, 50, 50))
activityIndicator.center = self.view.center
activityIndicator.hidesWhenStopped = true
activityIndicator.activityIndicatorViewStyle = UIActivityIndicatorViewStyle.Gray
view.addSubview(activityIndicator)
activityIndicator.startAnimating()
UIApplication.sharedApplication().beginIgnoringInteractionEvents()
//-------------------------------
user.signUpInBackgroundWithBlock {
(succeeded: Bool!, signupError: NSError!) -> Void in
//Stop activity indicator whether there is an error or not
self.activityIndicator.stopAnimating()
UIApplication.sharedApplication().endIgnoringInteractionEvents()
if signupError == nil {
// Hooray! Let them use the app now.
println("Registration Completed")
} else {
//Keep this here!
if let errorString = signupError.userInfo?["error"] as? NSString{
error = errorString
} else {
error = "Please try again later."
}
self.displayAlert("Could not Sign Up", error: error)
println(signupError)
}
}
}
//Print Confirmation to Cortana
}
//---------------------------------------
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view, typically from a nib.
passwordConfirmationMatch.hidden = true
//UITextField Delegate
self.userEmailAddress.delegate = self
self.userPasswordOne.delegate = self
self.userPasswordTwo.delegate = self
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
//Password Matching Function
func passwordCheck() {
if userPasswordTwo.text == userPasswordOne.text {
passwordConfirmationMatch.hidden = false
confirmedPassword = true
println("Password match")
} else {
passwordConfirmationMatch.hidden = true
confirmedPassword = false
println("Passwords don't match")
}
}
//Handle Keyboard
override func touchesBegan(touches: NSSet, withEvent event: UIEvent) {
self.view.endEditing(true)
passwordCheck()
}
func textFieldShouldReturn(textField: UITextField!) -> Bool {
userEmailAddress.resignFirstResponder()
userPasswordOne.resignFirstResponder()
userPasswordTwo.resignFirstResponder()
passwordCheck()
return true
}
}