问当用户退出我的iOS应用程序时，当他们下一次尝试使用Facebook登录时，他们必须重新输入他们的登录凭据。

EN

-(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];
        }
    }];

}

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];
}