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iOS Build a Self-Destructing Message iPhone App Using Parse.com as a Backend and Adding Users Logging In and Logging Out

Posted by Lisa Webb
Lisa Webb
Courses Plus Student 9,494 Points

Challenge Task 2/4 to work. I have tried what is available on the forums but keep getting the "Bummer" message.

import "MainViewController.h"

import "UIAlertView.h"

import <Parse/Parse.h>

@implementation LoginViewController

-(void)ViewDidLoad { [super viewDidLoad];

PFUser *currentUser; currentUser *[PFUser currentUser]; if (!currentUser) { [self performSegueWithIdentifier:@"showLogin" sender:self]; } } -(IBAction)logOut:(id)sender { [PFUser logOut]; [self performSegueWithIdentifier:@"showLogin" sender:self]; }

MainViewController.m 
#import "MainViewController.h"
#import "LoginViewController.h"
#import <Parse/Parse.h>
@implementation MainViewController

- (void)viewDidLoad {
    [super viewDidLoad];

    PFUser *currentUser;

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

- (IBAction)logOut:(id)sender {

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

@end
LoginViewController.m 
#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