In my game I don't want the GameCenter login popup appearing automatically when the app launches. So instead I have a GameCenter button that the user can tap to login with. When they press the button, the login screen appears.
However, it seems like when you launch the app again after logging in, the user still isn't "logged in". They still have to press the button again and then a little banner appears saying "Welcome back, User!". Is there a way to automatically relogin the user without them having to press the button each time? I already entered my credentials, why do I have to authenticate again?
Here is my code, when the user presses the button:
self.authenticatePlayer()
And here's the authenticate method:
func authenticatePlayer() {
let localPlayer = GKLocalPlayer.localPlayer()
localPlayer.authenticateHandler = {
(view, error) in
if view != nil {
self.view?.window?.rootViewController?.presentViewController(view!, animated: true, completion: nil)
} else {
}
}
}
I need something that can welcome back the user if they already logged in, but NOT ask them to login if they haven't logged in already.
To understand the behavior you're seeing, we need to look at how the authentication process works.
It starts when you set the authentication handler. This is the signal that tells your app to try and talk to Game Center. The authentication handler's completion block has three possible conditions:
Error: something went wrong
Receives a view controller: the login view controller tells you the player isn't logged in
Receives nil view controller: the lack of an error + lack of a view controller tells you the player was already logged in.
Although IOS may be aware of your login state (or attempting to fake your login state using cached info), your app loses that context when you exit. When you startup again, there's been no attempt to set the authentication handler, thus no attempt to verify authentication status until your user presses the button, thus your app doesn't know whether the user is logged in or not.
I think the following approach will get pretty close to what you're looking for:
set the authentication handler and initiate the authentication as early as possible in your first viewController's viewDidLoad. Do this as early as possible in your start up sequence.
If the user isn't authenticated, you will receive a login view controller. Don't present it. Instead, save it. Don't present it unless/until the user presses the button.
If the user is already logged in, they will see the welcome back message as soon as the game starts, and you'll be able to proceed since the user is still logged in.
Related
Auth.auth().signIn(withEmail:
In my case, When I first time open app and sign in firebase account like above code
then I reopen app
let user = Auth.auth().currentUser
user is not nil and then I reopen app get currentUser again user is nil that mean I did not sign in
I have the other app do like this, but the user always not nil.
I wonder why this happens.
Firebase automatically restores the authenticated user when the app restarts. But this requires a call to the servers, which may take some time. If you check Auth.auth().currentUser while the check is still in progress, you will get nil as the result.
To ensure you get the value once this initial check is done, use an auth state listener as shown in the first snippet in the documentation on getting the current user. From there:
Auth.auth().addStateDidChangeListener { auth, user in
// ...
}
Once this listener fires for the first time:
either the user variable will have a value if the user authentication state could be restored,
or it is nil if the user was not signed in last time the app ran, or the authentication state couldn't be restored (for example, because the account is disabled, or the password was changed).
I think it a big possibility you might be signed in on another device or signed in a different profile and didn't know, you might have some sync problems or security issues that did a safety measurement until you fix the security issue
When logging a user in or signing the user up for the first time and using phone auth it says:
Save the verification ID and restore it when your app loads. By doing
so, you can ensure that you still have a valid verification ID if your
app is terminated before the user completes the sign-in flow (for
example, while switching to the SMS app).
I'm not exactly sure what is the purpose of saving it.
0- the user opens the app and they are on the Login screen
1- the user adds their phone number (below)
2- the callback receives the authVerificationID
3- before the user is taken to the SMS screen, the app is somehow terminated
4- when the user opens the app again, because they haven't logged in yet, they are right back on the Login screen. When they enter their phone number again, they receive either a brand new authVerificationID or the same one (I'm not sure), and they are taken to the SMS screen. Either way both are valid and will get them to the SMS screen.
What does saving the authVerificationID do when no matter what, if the app is terminated, they have to add their phone number again because they will be back on the Login screen?
If the answer is "check if the authVerificationID is saved, and if it is then bring them to the SMS screen instead of the Login screen" then that is bad ux. The user might come back an hour later, when they first open the app they will see the SMS screen and be confused.
PhoneAuthProvider.provider().verifyPhoneNumber(phoneNumber, uiDelegate: nil) { (verificationID, error) in
guard let verificationID = verificationID else { return }
UserDefaults.standard.set(verificationID, forKey: "authVerificationID") // how does this help me?
// A. take user to sms view controller
// B. use authVerificationID && verificationCode for sms sign-in
}
The answer is pretty much what you said - if the user leaves your app in the middle of the auth flow, you can you can resume the sign-in flow from where they left off - i.e. the SMS verification step.
Once the user leaves your app, you have no guarantees that your app will not be terminated. It depends entirely on the OS. So your user might end up in a cycle where they just can't complete the sign-up (however unlikely this case is).
As for bad UX comment - it's very subjective (and depends on your design), and also time-dependent.
This is how users navigate through my app:
Enter a phone number
Enter verification number (This allows them access to my Firestore)
Enters a username
Now they're in the main app
Pretty straightforward however the problem is if the app crashes (for whatever reason) or closes when they are entering the username, they are still technically signed in to my Firestore.
It's a problem because I programmed the app such that when the user reopens the app, they immediately go to the main screen (I created an app manager to handle this). If they close the app (or if it crashes) before they enter a username, they can go right to the main screen without a username.
I've made several different attempts in the applicationWillTerminate method to track which view controller the user is in, sign out so that when the user open the app again, my App Manager says, Auth.auth().currentUser == nil and goes to the initial view controller to start the registration process again.
var viewController : UIViewController?
var vc = UsernameViewController()
if viewController == vc {
let firebaseAuth = Auth.auth()
do {
try firebaseAuth.signOut()
} catch let signOutError as NSError {
print ("Error signing out: %#", signOutError)
}
I expect the user who did not get a chance to create a username because the app closed or crashed to to return to the initial view controller rather than the main screen of the app.
I am currently experiencing the opposite.
Scenario:
I want to call the logout function if the app is terminated. I'm able to do it using native code:
- (void)applicationWillTerminate:(UIApplication *)app
{
// Run Logout function
}
Problem:
How to do it in IBM mobilefirst hybrid app?
// ************************************************
Edited
First of all, user login in to the app, if the user key in the correct user id and password, it will add the userIdentity into "loginRealm".
WL.Server.setActiveUser("loginRealm", userIdentity);
Next, user closes the apps without logout. So, when the user login for the another time, MFP server will not return any feedback since it will hit this exception:
Cannot change identity of an already logged in user in realm
'loginRealm'. The application must logout first.
Hence, I have to logout the user from MFP server by setting the "loginRealm" to null in adapter;
WL.Server.setActiveUser("loginRealm", null);
The above line of code is in the logout function defined in authentication-config.xml.
The client side device runs this line of code and it will trigger the logout function. Besides, it will reload the App upon success:
WL.Client.logout('loginRealm', {
onSuccess: WL.Client.reloadApp
});
Steps that I've tried:
1) At WlcommonInit() I added WL.Client.updateUserInfo(); and if WL.Client.isUserAuthenticated("loginRealm") return true I will logout the user from server. However, WL.Client.isUserAuthenticated("loginRealm") will always return false. This is because, it needs to take sometime around (30seconds to 2 minutes) for the flag to turn true after WL.Client.updateUserInfo();. So my login still fail and hit the same error.
2) I tried to logout the users during the user click login button. But the app will refresh and return to login page again due to reloadApp. The logout code I get from IBM mobilefirst website. So user need to click and type 2 times in order to login into the main menu.
WL.Client.logout('loginRealm', {
onSuccess: WL.Client.reloadApp
});
Am I doing it wrongly? Or are there any other methods to get WL.Client.isUserAuthenticated("loginRealm") return true instantly after WL.Client.updateUserInfo(); ? Can we remove the reload app line of code in logout function?
I don't think this is doable, because that logout function (in MFP) will require server connectivity (request and response) and if the app is by then killed, I think it's going to cause unpredictable results.
Note though that it seems to be not recommended to use that function anyway? applicationWillTerminate when is it called and when not
What you should do perhaps in order to simulate it, is to logout-on-login, so that it would appear that the app is logged out when opening it. You can extend the duration of the splash screen so that the end-user will not see that s/he is logged in (in case the session was still alive between the closing and re-opening of the app), until really logged out and then you can display the login screen again or any other required screen.
In my iOS app I made a Login page as the entry point of the app (using storyboard)
However I don't want the user to see the login page each time he uses the app, so I thought of launching the Home page of the app if the user already performed a login in the past.
For that I started to save the login act with NSUserDefaults but I do not know in which of the LoginViewController method I should check for it? Also, is this way to feature "auto logging" a good practice?
Best place is in application:didFinishLaunchingWithOptions
if ([[NSUserDefaults standardUserDefaults] integerForKey:#"UserID"]==0) {
//no user login go back to login page
}
else{
//go in main screen of you application as user already login "root" is storyboard ID of main screen
self.window.rootViewController=[self.window.rootViewController.storyboard instantiateViewControllerWithIdentifier:#"root"];
}