ios - Swift 中的 PFUser logInWithUsernameInBackground - 参数 'target' 调用缺少参数

Question

我正在为用 Swift 编写的 Parse 实现登录功能。我收到一个错误:

Missing argument for parameter 'target' call

虽然我似乎没有遗漏任何参数 - 我遵循 PFUser.h 中的声明。

这是我的代码:

//Declarations
@IBOutlet weak var usernameTextField: UITextField!
@IBOutlet weak var passwordTextField: UITextField!

@IBAction func loginButtonPressed(sender: UIButton) {
    let userEmail = usernameTextField.text
    let userPassword = passwordTextField.text

    //Check that both fields are filled
    if usernameTextField != "" && passwordTextField != "" {
        PFUser.logInWithUsernameInBackground(userEmail, password: userPassword) {
            (user: PFUser, error: NSError) -> Void in {
    }
}

感谢您的帮助!

Answer 1

你有额外的大括号，用户名和密码检查错误。试试下面的代码(请复制和粘贴)它有效:

@IBAction func loginButtonPressed(sender: UIButton) {
    let userEmail = usernameTextField.text
    let userPassword = passwordTextField.text

    if !userEmail.isEmpty && !userPassword.isEmpty {
        PFUser.logInWithUsernameInBackground(userEmail, password: userPassword) { (user, error) -> Void in
            if error == nil {
                println("succesful")
            } else {
                println("error: \(error!.userInfo!)")
            }
        }
    }
}