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Caleb Kleveter
Treehouse Moderator 37,862 PointsLogging in and logging out. Part 2/4
I completely bamboozled over this one, I searched the forums an I couldn't find a helpful post. Best to all!
#import "MainViewController.h"
#import "LoginViewController.h"
#import <Parse/Parse.h>
@implementation MainViewController
- (void)viewDidLoad {
[super viewDidLoad];
PFUser *currentUser;
PFUser *currentUser = [PFUsr currentUser];
if (currentUser == nil) {
[self performSegueWithIdentifier:@"showLogin" sender:self];
}
- (IBAction)logOut:(id)sender {
[self performSegueWithIdentifier:@"showLogin" sender:self];
}
@end
#import "LoginViewController.h"
#import "UIAlertView.h"
#import <Parse/Parse.h>
@implementation LoginViewController
- (void)viewDidLoad {
[super viewDidLoad];
}
- (IBAction)login:(id)sender {
// This is an example of how to declare a block named loginHandler. It starts with a
// return type, then the name of the block with a special syntax for naming. The next
// set of parentheses hold the parameters and their types. Then assigning the block
// on the right side looks just like how we defined it in the video (carat with the
// same parameters in parentheses).
void (^loginHandler)(PFUser *user, NSError *error) = ^(PFUser *user, NSError *error) {
if (error) {
UIAlertView *alertView = [[UIAlertView alloc] initWithTitle:@"Sorry!"
message:@"Error logging in."
delegate:nil cancelButtonTitle:@"OK" otherButtonTitles:nil];
[alertView show];
}
else {
[self.navigationController popToRootViewControllerAnimated:YES];
}
};
// Add your code below!
}
@end
3 Answers
Steve Hunter
57,712 PointsAnd you've declared the PFUser instance twice:
PFUser *currentUser;
PFUser *currentUser = [PFUser currentUser];
Needs to be:
PFUser *currentUser = [PFUser currentUser];
Or over two lines like:
PFUser *currentUser;
currentUser = [PFUser currentUser];
Steve Hunter
57,712 PointsTypo here -> PFUser *currentUser = [PFUsr currentUser];
PFUsr not PFUser ... does that fix it?
Steve.
Caleb Kleveter
Treehouse Moderator 37,862 PointsHi Steve,
In the code challenge " PFUser *currentUser;" is already there, the instructions are: "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."
I tried the following code:
currentUser = [PFUser currentUser];
if (currentUser) {
And I got this error: "Bummer! Don't forget to prevent performSegueWithIdentifier from being called! Hint: Check if 'currentUser' is nil."
Caleb Kleveter
Treehouse Moderator 37,862 PointsI got it, my code looks like this:
currentUser = [PFUser currentUser];
if (currentUser == nil) {