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General Discussion

Posted by Jake Sieradzki
Jake Sieradzki
9,732 Points

Logging In and Logging Out Code Challenge

In the code challenge for logging in and logging out, I keep getting this wrong and I don't know if I'm being stupid but I really can't figure it out...

It's part 2 of 4 with this question: In viewDidLoad we see that the LoginViewController is presented automatically. Set the 'currentUser' variable using the appropriate method from the PFUser class. Then use that variable in an if statement to only perform the segue to LoginViewController if no user is logged in.

Here's my code:

#import "MainViewController.h"
#import "LoginViewController.h"
#import <Parse/Parse.h>

@implementation MainViewController

- (void)viewDidLoad {
    [super viewDidLoad];

    PFUser *currentUser = [PFUser currentUser];
    if (currentUser == nil) {
        [self performSegueWithIdentifier:@"showLogin" sender:self];
    }

    [self performSegueWithIdentifier:@"showLogin" sender:self];
}

- (IBAction)logOut:(id)sender {

    [self performSegueWithIdentifier:@"showLogin" sender:self];
}

@end
cameron swenson
cameron swenson
9,951 Points

You are calling the method :

[self performSegueWithIdentifier:@"showLogin" sender:self]

two times. Once inside the scope of :

if (currentUser == nil) {
    }

which is correct. The second time is in the scope of:

- (void)viewDidLoad {
}

which would be causing your conflict.

I much prefer using the statement below because it also sets up a a way for us to act on if the currentUser exists:

- (void)viewDidLoad {
    [super viewDidLoad];

    PFUser *currentUser;
    currentUser = [PFUser currentUser];
    if (currentUser) {
    }
else {
    [self performSegueWithIdentifier:@"showLogin" sender:self];
    }
}

1 Answer

agreatdaytocode
agreatdaytocode
24,757 Points
agreatdaytocode
agreatdaytocode
24,757 Points 
#import "MainViewController.h"
#import "LoginViewController.h"
#import <Parse/Parse.h>

@implementation MainViewController

- (void)viewDidLoad {
    [super viewDidLoad];


PFUser *currentUser = [PFUser currentUser];
if (currentUser) {
    // do stuff with the user
} else {
    // show the signup or login screen
}
}



- (IBAction)logOut:(id)sender {

    [self performSegueWithIdentifier:@"showLogin" sender:self];
}

@end