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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 Des Gayle
Des Gayle
2,987 Points

Using Parse.com as a Backend code challenge

Any idea why this line of code is not correct?

PFUser logInWithUsernameInBackground:@"test" password:@"test" block:^(loginHandler);

1 Answer

Stone Preston
Stone Preston
42,016 Points
Stone Preston
Stone Preston
42,016 Points

you need brackets around the method call. also all you have to pass in for the block parameter is the name of the block, you dont need ^() around it.

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

also be sure you place this code below the block definition:

- (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];

}
Des Gayle
Des Gayle
2,987 Points

Gah! So close! I swear, as soon as I go to sleep I forget everything.

Thanks a lot, really appreciate it.

-DG