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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 Brett Abamonte
Brett Abamonte
7,564 Points

Code Challenge Help, totally stuck!!

Challenge task 3 of 4 Now switch to LoginViewController.m. Blocks can also be declared and passed around as variables, as we can see in the existing code below. This code declares a block named loginHandler on line 17. In the login method (where it says "Add your code below!"), add a call to the PFUser class method logInWithUsernameInBackground:password:block:. Use @"test" as the 1st and 2nd parameters. Then pass in loginHandler as the 3rd parameter.

I don't know what the @"test" is and I don't know how to pass the loginHandler as the third parameter.

My code is [PFUser logInWithUsernameInBackground:username password:password block:^(@"test", @"test", (^loginHandler)){ }];

CAN ANYBODY HELP!!!!!!

2 Answers

agreatdaytocode
agreatdaytocode
24,757 Points
agreatdaytocode
agreatdaytocode
24,757 Points

Try this:

- (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!
    [PFUser logInWithUsernameInBackground:@"test" password:@"test" block:loginHandler];

}
Brett Abamonte
Brett Abamonte
7,564 Points
Brett Abamonte
Brett Abamonte
7,564 Points

Thanks!!