object cannot be nil - On a segue?

Question

All I want to do in my code is move from one view to another. No matter how many different ways I try to go around it, any segue or any change from the current view causes this error:

*** Terminating app due to uncaught exception 'NSInvalidArgumentException',
reason: '*** -[__NSArrayM insertObject:atIndex:]: object cannot be nil'

There's no indication of what object it's talking about at all, and the app is crashing on my segue line. Oh and I'm using Xcode 5-DP and iOS 7. Here's my source:

LoginViewController.h

#import <UIKit/UIKit.h>
#import "ECSlidingViewController.h"
#import "MenuViewController.h"
#import <MessageUI/MessageUI.h>
#import <CoreData/CoreData.h>

@interface LoginViewController : UIViewController <UITextFieldDelegate>
@property (weak, nonatomic) IBOutlet UITextField *userTextField;
@property (weak, nonatomic) IBOutlet UITextField *passwordTextField;

- (IBAction)signupTouched:(UIButton *)sender;
- (IBAction)logInPressed:(id)sender;
- (IBAction)backgroundTouched:(id)sender;
- (IBAction)revealMenu:(id)sender;
@end

LoginViewController.m (Exception on line 8)

#import "LoginViewController.h"
#import "RegisterView.h"
#import <Parse/Parse.h>

@implementation LoginViewController

- (IBAction)signupTouched:(UIButton *)sender {
    [self performSegueWithIdentifier:@"signup" sender:self];
    //                    THE APPLICATION CRASHES ON THIS LINE ABOVE
}

//Login button pressed
-(IBAction)logInPressed:(id)sender
{
    //If user logged succesful:
    //[self performSegueWithIdentifier:@"LoginSuccesful" sender:self];

    if (![self.userTextField.text isEqual:@""]) {
        [PFUser logInWithUsernameInBackground:self.userTextField.text password:self.passwordTextField.text block:^(PFUser *user, NSError *error) {
            if (user) {
                //Open the wall
                //[self performSegueWithIdentifier:@"LoginSuccesful" sender:self];
                UIAlertView *loginAlertView = [[UIAlertView alloc] initWithTitle:@"Great!"  message:@"You have logged in" delegate:nil cancelButtonTitle:@"Get roaming" otherButtonTitles:nil, nil];
                [loginAlertView show];
            } else {
                //Something bad has ocurred
                NSString *errorString = [[error userInfo] objectForKey:@"error"];
                UIAlertView *errorAlertView = [[UIAlertView alloc] initWithTitle:@"Error" message:errorString delegate:nil cancelButtonTitle:@"Ok" otherButtonTitles:nil, nil];
                [errorAlertView show];
            }
        }];
    } else {
        //Something bad has ocurred
        NSString *errorString = @"You did not type any credentials!";
        UIAlertView *errorAlertView = [[UIAlertView alloc] initWithTitle:@"Error" message:errorString delegate:nil cancelButtonTitle:@"Okay" otherButtonTitles:nil, nil];
        [errorAlertView show];
    }
}

- (IBAction)backgroundTouched:(id)sender {
    [self.userTextField resignFirstResponder];
    [self.passwordTextField resignFirstResponder];
}

- (BOOL)textFieldShouldReturn:(UITextField *)textField {
    [textField resignFirstResponder];
    return NO;
}

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

    if (![self.slidingViewController.underLeftViewController isKindOfClass:[MenuViewController class]]) {
        self.slidingViewController.underLeftViewController = [self.storyboard instantiateViewControllerWithIdentifier:@"Menu"];
    }
    self.slidingViewController.underRightViewController = nil;

    [self.view addGestureRecognizer:self.slidingViewController.panGesture];
}

- (IBAction)revealMenu:(id)sender
{
    [self.slidingViewController anchorTopViewTo:ECRight];
}

- (void)viewDidLoad
{
    [super viewDidLoad];
    self.userTextField.delegate = self;
    self.passwordTextField.delegate = self;
    // Do any additional setup after loading the view.
}

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

- (void)viewDidUnload {
    [self setUserTextField:nil];
    [self setPasswordTextField:nil];
    [super viewDidUnload];
}
@end

I've googled, and I've googled. No-one else seems to be having an issue like this. I tried cleaning out my entire iOS Simulator and everything to no avail, following a solution that appeared to work for others. I've tried every type of segue possible and none are working.

Thanks in advance!

Answer 1

Recheck your configuration and use of the ECSlidingViewController, and it's topViewController.