Cannot get optional method of PFLoginViewControllerDelegate to implement properly when using Parse.com Framework

Question

I have been trying to get this to work for the past 4 hours. I actually did get it to work about an hour ago, but then came back after a break, played with the code a little, and now it is not working again.

I am trying to implement an optional BOOL method that is declared in PFLoginViewControllerDelegate and it looks like this:

-(BOOL)logInViewController:(PFLogInViewController *)logInController shouldBeginLogInWithUsername:(NSString *)username password:(NSString *)password;

In this Parse tutorial here, it says to paste the following code in to define this BOOL method:

// Sent to the delegate to determine whether the log in request should be submitted to the server.
-(BOOL)logInViewController:(PFLogInViewController *)logInController shouldBeginLogInWithUsername:(NSString *)username password:(NSString *)password {
// Check if both fields are completed
if (username && password && username.length != 0 && password.length != 0) {
    return YES; // Begin login process
}

[[[UIAlertView alloc] initWithTitle:@"Missing Information"
                      message:@"Make sure you fill out all of the information!"
                      delegate:nil
                      cancelButtonTitle:@"ok"
                      otherButtonTitles:nil] show];
return NO; // Interrupt login process
}

The problem is that I do not get the proper alert view window with a title of "Missing Information" and a body of "Make sure you fill out all of the information!".

I get an alert view window with the title of "Account Error" and a body of "Please double-check your information and try again".

Why is this BOOL method not working properly for me?

Below is the code inside of my View Controller's header file:

#import <Parse/Parse.h>

@interface ParseLoginViewController : PFLogInViewController <PFLogInViewControllerDelegate, PFSignUpViewControllerDelegate>

@end

Below is the code inside of my View Controller's main file:

#import "ParseLoginViewController.h"
#import <Parse/Parse.h>

@interface ParseLoginViewController ()

@end

@implementation ParseLoginViewController

- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil
{
self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil];
if (self) {
    // Custom initialization
}
return self;
}

- (void)viewDidLoad
{
[super viewDidLoad];
// Do any additional setup after loading the view.

}

- (void)didReceiveMemoryWarning
{
[super didReceiveMemoryWarning];
// Dispose of any resources that can be recreated.
}

- (void)viewDidAppear:(BOOL)animated {
[super viewDidAppear:animated];

if (![PFUser currentUser]) { // No user logged in
    // Create the log in view controller
    PFLogInViewController *logInViewController = [[PFLogInViewController alloc] init];
    [logInViewController setDelegate:self]; // Set ourselves as the delegate

    // Create the sign up view controller
    PFSignUpViewController *signUpViewController = [[PFSignUpViewController alloc] init];
    [signUpViewController setDelegate:self]; // Set ourselves as the delegate

    // Assign our sign up controller to be displayed from the login controller
    [logInViewController setSignUpController:signUpViewController];

    // Present the log in view controller
    [self presentViewController:logInViewController animated:YES completion:NULL];

}

}

// Sent to the delegate to determine whether the log in request should be submitted to the server.
- (BOOL)logInViewController:(PFLogInViewController *)logInController shouldBeginLogInWithUsername:(NSString *)username password:(NSString *)password {
// Check if both fields are completed
if (username && password && username.length != 0 && password.length != 0) {
    return YES; // Begin login process
}

[[[UIAlertView alloc] initWithTitle:@"Missing Information"
                            message:@"Make sure you fill out all of the information!"
                           delegate:nil
                  cancelButtonTitle:@"ok"
                  otherButtonTitles:nil] show];
return NO; // Interrupt login process
}


@end

Answer 1

Your UIAlertView is showing but getting dismissed quickly as another UIAlertView from SDK is kicking in.

From quick search that, as you know you won't be able to change ParseSDK. But you might be able to override the UIAlertView String via LocalisedString

NSString *ok = NSLocalizedString(@"OK", @"OK");
NSString *title = NSLocalizedString(@"Missing Information", @"Account Error");
NSString *message = NSLocalizedString(@"Make sure you fill out all of the information!", @"Please double-check your information and try again");

Ref: https://parse.com/questions/override-default-pfloginviewcontroller-login-error