presentModalView not shown when called inside delegate

Question

I have a UIViewController called MainViewController (it is inside a navigationController). I have another UIViewController called OptionsViewController. Inside OptionsViewController I have a logout button and when clicked it calls a delegate in the MainViewController:

- (IBAction) logout:(id)sender
{
    [self.delegate viewController:self loginSuccess:YES]; //calls this delegate

    NSUserDefaults *standardDefaults = [NSUserDefaults standardUserDefaults];
    NSString * username = [standardDefaults stringForKey:@"kApplicationUserNameKey"]; 
    NSError * error = nil;

    [standardDefaults removeObjectForKey:@"kApplicationUserNameKey"];
    [SFHFKeychainUtils deleteItemForUsername:username andServiceName:@"convore" error:&error];
    [self dismissModalViewControllerAnimated:YES];
}

The delegate called at MainViewController is:

- (void) viewController:(OptionsViewController*)viewCon loginSuccess:(BOOL)loadFlag
{
    if (loadFlag){
        LoginViewController* lvc = [[LoginViewController alloc] init];
        lvc.delegate = self;
        [self.navigationController presentModalViewController:lvc animated:YES];
          //this same code works in the viewDidLoad (it presents the LoginViewController, but not here)
        [lvc release];

        [self.groups removeAllObjects];
        [self.table reloadData];

        Topic * topic = [Topic object];
        topic.tid = [NSNumber numberWithInt:-2];
        self.detailViewController.topic = topic;
        self.detailViewController.detailItem = topic.tid;
    }
}

The issue is that when this delegate is called, it should present a LoginViewController (as can be seen from the code above), however it doesn't. I tried to put the presentModalViewController code in the delegate inside the viewDidLoad of MainViewController and it shows up, but when trying to show it in this delegate it doesn't. Why is this? And yes I checked the delegate is getting called (tried putting a NSLog inside the delegate)

UPDATE:

The OptionsViewController is shown as a modalViewController as well with the following code from MainViewController:

- (IBAction)showOptions:(id)sender
{
    if ([self.detailViewController.message isFirstResponder])
        [self.detailViewController setViewMovedUp:NO];


    OptionsViewController * opt = [[OptionsViewController alloc] init];
    opt.delegate = self;
    opt.mgvc = self;
    UINavigationController * uinc = [[UINavigationController alloc] initWithRootViewController:opt];
    uinc.navigationBar.tintColor = [UIColor blackColor];
    uinc.modalPresentationStyle = UIModalPresentationFormSheet;
    uinc.title = @"";
    uinc.modalTransitionStyle = UIModalTransitionStyleFlipHorizontal;  //transition shouldn't matter
    [self presentModalViewController:opt animated:YES];

    float xCenter = 384;
    float yCenter = 512;
    if (self.splitViewController.interfaceOrientation == UIInterfaceOrientationPortrait || self.splitViewController.interfaceOrientation == UIInterfaceOrientationPortraitUpsideDown){
        xCenter = 384;
        yCenter = 512;
    } else if (self.splitViewController.interfaceOrientation == UIInterfaceOrientationLandscapeLeft || self.splitViewController.interfaceOrientation == UIInterfaceOrientationLandscapeRight){
        xCenter = 512;
        yCenter = 384;
    }

    uinc.view.superview.frame = CGRectMake(0, 0 , 318, 209);//it's important to do this after presentModalViewController
    uinc.view.superview.center = CGPointMake(xCenter, yCenter);
    [opt release];

}

When I try to just show OptionsViewController itself (without the UINavigationController, everything works fine). Why is this?

Answer 1

Are you sure your view is inside a navigation controller? If not, change the line to:

[self presentModalViewController:lvc animated:YES];