问题
I am using Xcode, Swift, and Parse. When I try and logout a PFUser, i never get a return of nil.
In this part of the app, the viewController is simply showing a few buttons one logs in. One sends the user to signup. One sends the user to change details, and one is a simple logout.
The code for the two that matter on logout is;
@IBAction func logout(sender: AnyObject) {
PFUser.logOut()
var currentUser = PFUser.currentUser()
self.displayAlert("You are now logged out", error: "")
println(currentUser!)
}
@IBAction func changeDetails(sender: AnyObject) {
var currentUser = PFUser.currentUser()
println(currentUser!)
if currentUser != nil {
let nextView30 = self.storyboard?.instantiateViewControllerWithIdentifier("changeDetails") as! changeUserDetailsViewController
self.navigationController?.pushViewController(nextView30, animated: true)
} else {
self.displayAlert("Please log in", error: "")
}
}
Once the code runs and I logout, wherever the currentUser gets read I get the following type of response, not nil. The next ViewController is actioned, and this shouldn't happen without a usr logged in.
PFUser: 0x37018fbc0, objectId: new, localId: local_3b5eb7453f9af5ed { }
Am I doing something wrong or is this standard? If it is correct, how do I return no user logged in?
Thanks
回答1:
if PFUser.currentUser()!.username != nil
{
self.performSegueWithIdentifier("loginSegue", sender: self)
}
The above code worked for the login issue. But i still have the logout issue. After I call PFUser.logout(), PFUser.currentUser() is not becoming nil. Any help?
Thanks
回答2:
I've been struggling with logging out for a little while and I believe I have finally cracked it!
No matter what I did, when I used "PFUser.logOut()" would never set "PFUser.currentUser()" to nil, but it would set "PFUser.currentUser()!.username" to nil...
Because of this I used
var currentUser = PFUser.currentUser()!.username
as a global variable to track is a user is logged in.
On my login/first page I added
override func viewDidAppear(animated: Bool) {
if currentUser != nil {
self.performSegueWithIdentifier("login", sender: self)
}
}
and finally on my logout button i used
override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
if segue.identifier == "logout" {
PFUser.logOut() //Log user out
currentUser = PFUser.currentUser()!.username //Reset currentUser variable to nil
}
}
I hope that helps!
回答3:
Try commenting out the following line of code in your AppDelegate.swift file -
PFUser.enableAutomaticUser()
enableAutomaticUser() will log in an anonymous user once you call PFUser.logOut(), and the username for an anonymous user is nil.
回答4:
override func viewDidLoad(animated: Bool) {
var currentUser = PFUser.currentUser()?.username
if(currentUser != nil){
var loginAlert: UIAlertController = UIAlertController(title: "Signup/ Login", message:"Please Signup or Login" , preferredStyle: UIAlertControllerStyle.Alert)
loginAlert.addTextFieldWithConfigurationHandler({
textfield in
textfield.placeholder = "Your Username"
})
loginAlert.addTextFieldWithConfigurationHandler({
textfield in
textfield.placeholder = "Your Password"
textfield.secureTextEntry = true
})
loginAlert.addAction(UIAlertAction(title: "Login", style: UIAlertActionStyle.Default, handler: {alertAction in
let textFields: NSArray = loginAlert.textFields! as NSArray
let usernameTextFields: UITextField = textFields.objectAtIndex(0) as! UITextField
let passwordTextFields: UITextField = textFields.objectAtIndex(1) as! UITextField
PFUser.logInWithUsernameInBackground(usernameTextFields.text as String!, password: passwordTextFields.text as String!){
(loggedInuser: PFUser?, signupError: NSError?) -> Void in
if((loggedInuser) != nil){
println("User logged in successfully")
}else{
println("User login failed")
}
}
}))
loginAlert.addAction(UIAlertAction(title: "SignUp", style: UIAlertActionStyle.Default, handler: {alertAction in
let textFields: NSArray = loginAlert.textFields! as NSArray
let usernameTextFields: UITextField = textFields.objectAtIndex(0) as! UITextField
let passwordTextFields: UITextField = textFields.objectAtIndex(1) as! UITextField
var sweeter : PFUser = PFUser()
sweeter.username = usernameTextFields.text
sweeter.password = passwordTextFields.text
sweeter.signUpInBackgroundWithBlock {(sucess,error) -> Void in
if !(error != nil){
println("sign up success")
}else
{
println("constant error string\(error)")
}
}
}))
self.presentViewController(loginAlert, animated: true, completion: nil)
}
}
来源：https://stackoverflow.com/questions/30216819/swift-parse-pfuser-currentuser-never-equals-nil