How can I call this function in viewDidLoad() in iOS8 - swift

Question

I want to call this function in viewDidLoad but I don't know how one would do this. Can you please help me?
func loginWithFacebook(withcompletionHandler: (success:Bool) ->()){
var permissions : Array = [ "user_location","public_profile"]
PFFacebookUtils.logInInBackgroundWithReadPermissions(permissions, {
(user: PFUser?, error: NSError?) -> Void in
if let user = user {
if user.isNew {
println("User SIGNED UP and logged in through Facebook!")
self.fetchUserInforFromFacebook(withcompletionHandler)
println("User logged in through Facebook!")
withcompletionHandler(success: true)
}
} else {
println("Uh oh. The user cancelled the FACEBOOK LOGIN.")
self.showErrorMessage(error!)
withcompletionHandler(success: false)
}
})
}

Answer 1

If you call function with in function
override func viewDidLoad() {
super.viewDidLoad()
self.loginWithFacebook { (success) -> () in
// Your code.
}
}
if you want call it in same function then
override func viewDidLoad() {
super.viewDidLoad()
loginWithFacebook { (success) -> () in
// Your code.
}
}

Answer 2

override func viewDidLoad() {
super.viewDidLoad()
self.loginWithFacebook { (success) -> () in
if success { //succeeded } else { //failed } }
}
}

Answer 3

So in order to call your method, add this to your viewDidLoad:
override func viewDidLoad() {
super.viewDidLoad()
self.loginWithFacebook { (success) -> () in
// Your code.
}
}