Swift - 解析 "Signing Up"错误

Question

var user = PFUser()
    user.username = username.text
    user.password = password.text

    user.signUpInBackgroundWithBlock {
        (succeeded: Bool!, signupError: NSError!) -> Void in

        self.activityIndicator.stopAnimating()
            UIApplication.sharedApplication().endIgnoringInteractionEvents()

            if signupError == nil  {
                // Hooray! Let them use the app now.

                println("signed up")

我在 user.signUpInBackgroundWithBlock {

处遇到错误

它说:

Function signature (Bool!, NSError!) -> is not compatible with expected type @obj_block (Bool, NSError!) - > Void

此代码来自教程视频。 Parse 当前的“Signing Up”代码看起来与这段代码不同

Answer 1

succeeded 应该是 bool 值而不是可选值。像这样删除感叹号:

(成功:Bool，注册错误:NSError!)