对于我的应用程序，它需要用户登录。如果用户登录无效，我需要让用户知道这一点。所以我想知道如果登录参数无效，如何调出 UIAlertView。它会自动在终端中让我知道其是否有效。但我需要知道如何创建 AlertView，以便用户知道他们是否成功输入了信息。
代码
IBAction func loginTapped(sender: AnyObject) {
let username = usernameField.text
let password = passwordField.text
if username.isEmpty || password.isEmpty {
var emptyFieldsError:UIAlertView = UIAlertView(title: "Please try again", message: "Please fill in all the fields we can get you logged in to your account.", delegate: self, cancelButtonTitle: "Try again")
emptyFieldsError.show()
}
PFUser.logInWithUsernameInBackground(username, password:password) {
(user: PFUser?, error: NSError?) -> Void in
if user != nil {
println("Sucessful")
} else {
println("Invalid login")
}
}
}
最佳答案
试试这个..:
// Mark: Error message alert.
var errorMessage = String()
func alertView(title: String, message: String, buttonName: String){
var alert:UIAlertController = UIAlertController(title: title, message: message, preferredStyle: UIAlertControllerStyle.Alert)
alert.addAction(UIAlertAction(title: buttonName, style: UIAlertActionStyle.Default, handler: { (action) -> Void in
self.dismissViewControllerAnimated(true, completion: nil)
}))
self.presentViewController(alert, animated: true, completion: nil)
}
@IBAction func loginTapped(sender: AnyObject) {
PFUser.logInWithUsernameInBackground(userName.text, password: password.text) { (user: PFUser?, error: NSError?) -> Void in
if user != nil {
// user logged in.. Perform Segue here..
self.performSegueWithIdentifier("a", sender: self)
} else {
// Show error here..
if let errorString = error!.userInfo?["error"] as? String {
self.errorMessage = errorString
}
self.alertView("Error!", message: self.errorMessage, buttonName: "Try again")
}
}
}
关于ios - 在 Parse (Swift) 中接受登录参数，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/32281290/