let user = PFUser()

user.email = emailAddress.text
user.username = screenName.text
user.password = password.text

let image = self.profilePic.image

if image != nil {

    let imagedata = UIImagePNGRepresentation(image!)!

        let file = PFFile(name: "image.png", data: imagedata)

        user["profilePic"] = file

    }

    user.signUpInBackground(block: { (success, error) in

        if error != nil {

            // error code

        } else {

            // user logged in successfully

        }
    }
}