当用户注销我的iOS应用程序时，下次他们尝试使用Facebook登录时，应该重新输入其登录凭据

Question

I'm building an iOS app with Parse and Facebook frameworks.

I log the user in

-(void)updateUserInformation
{

    FBRequest *request = [FBRequest requestForMe];

    [request startWithCompletionHandler:^(FBRequestConnection *connection, id result, NSError *error) {

        if (!error){

            NSDictionary *userDictionary = (NSDictionary *)result;

            NSString *facebookID = userDictionary[@"id"];
            NSURL *pictureURL = [NSURL URLWithString:[NSString stringWithFormat:@"https://graph.facebook.com/%@/picture?type=large&return_ssl_resources=1", facebookID]];

            NSMutableDictionary *userProfile = [[NSMutableDictionary alloc]initWithCapacity:8];
            if (userDictionary[@"name"]){
                userProfile[kJFUserProfileNameKey] = userDictionary[@"name"];
            }
            if (userDictionary[@"first_name"]){
                userProfile[kJFUserProfileFirstNameKey] = userDictionary[@"first_name"];
            }
            if (userDictionary[@"location"][@"name"]){
                userProfile[kJFUserProfileLocationKey] = userDictionary[@"location"][@"name"];
            }
            if (userDictionary[@"gender"]){
                userProfile[kJFUserProfileGenderKey] = userDictionary[@"gender"];
            }
            if (userDictionary[@"birthday"]){
                userProfile[kJFUserProfileBirthdayKey] = userDictionary[@"birthday"];
                NSDateFormatter *formatter = [[NSDateFormatter alloc]init];
                [formatter setDateStyle:NSDateFormatterShortStyle];
                NSDate *date = [formatter dateFromString:userDictionary[@"birthday"]];
                NSDate *now = [NSDate date];
                NSTimeInterval seconds = [now timeIntervalSinceDate:date];
                int age = seconds / 31536000;
                userProfile[kJFUserProfileAgeKey] = @(age);
            }
            if (userDictionary[@"interested_in"]){
                userProfile[kJFUserProfileInterestedInKey] = userDictionary[@"interested_in"];
            }
            if (userDictionary[@"relationship_status"]){
                userProfile[kJFUserProfileRelationshipStatusKey] = userDictionary[@"relationship_status"];
            }
            if ([pictureURL absoluteString]){
                userProfile[kJFUserProfilePictureURL] = [pictureURL absoluteString];
            }

            [[PFUser currentUser] setObject:userProfile forKey:kJFUserProfileKey];
            [[PFUser currentUser] saveInBackground];

        }

    }];

}

#pragma mark - from initial login controller



- (IBAction)loginWithFBButtonPressed:(UIButton *)sender {

    NSArray *permissionsArray = @[ @"user_about_me", @"user_relationships", @"user_birthday", @"user_location", @"user_friends"];

    [PFFacebookUtils logInWithPermissions:permissionsArray block:^(PFUser *user, NSError *error) {
        [_activityIndicator stopAnimating]; // Hide loading indicator

        if (!user) {
            if (!error) {
                NSLog(@"Uh oh. The user cancelled the Facebook login.");
            } else {
                NSLog(@"Uh oh. An error occurred: %@", error);
            }
        } else{
            [self performSegueWithIdentifier:@"loginToMainSegue" sender:self];
            [self updateUserInformation];
        }
    }];

}

No problem logging users in or out. But when I do log the user out and pop to the root view controller (the one with the "login with facebook" button), if I click that button, Facebook opens on a Safari tab with the last user's Facebook account already active. Instead of having to enter login information, the user gets the message "You have already authorized thisApp " and a "cancel" and "ok" button.

The logout button is occurring from within a TableViewController.

[UPDATE 1]

Even after implementing these additional methods, my user is still logged into Facebook. I tried the unLink method but that doesn't seem to be what I'm after, because after doing that, when I log a user back in, that user's in-app data no longer is attributed to him.

if (indexPath.row == 3) {
    identifier = nil;

    NSLog(@"pressed logout");

    [PFUser logOut];
    [[PFFacebookUtils session]closeAndClearTokenInformation];
    [[PFFacebookUtils session]close];
    [[FBSession activeSession]closeAndClearTokenInformation];
    [[FBSession activeSession]close];
    [FBSession setActiveSession:nil];

    [self.navigationController popToRootViewControllerAnimated:YES];
}

What do I have to do to actually log the user out of Facebook from the phone itself, as opposed to just from this current session on the app?

Answer 1

hi don't know which Facebook sdk you are using but normally for logout from Facebook you have to clear token information and close session refer developers.facebook and following links.

http://developers.facebook.com/docs/reference/ios/3.0/class/FBSession/

http://developers.facebook.com/docs/reference/ios/3.0/class/FBSession/#close

[FBSession.activeSession closeAndClearTokenInformation];
[FBSession.activeSession close];
[FBSession setActiveSession:nil];

you can also check this two question related your issue :-

Facebook graph api log out not working

Facebook iOS SDK 3.1.1 "closeAndClearTokenInformation" method no working

hope its helps you

Answer 2

Try unlinking the user object from Facebook before you logout.

[PFFacebookUtils unlinkUserInBackground:[PFUser currentUser] block:^(BOOL Success,NSError *unlinkError){
                    if(!unlinkError){
                        // User unlinked
                    }else{
                       // Erro while unlink user
                    }
                }];

Answer 3

Your app can choose to use Facebook for login, and control login/logout on your app only.

The login to their Facebook account is done by proxy if needed, but you can't log them out of Facebook, as that would impact all other apps using Facebook.

If the user wants to log out of Facebook they either use the Facebook app or do it in the Settings on their device.