Question

I have a UIViewController called LoginViewController. The UIViewController has two UITextField, username and password. This is displayed as a modalViewController when the first time the app is launched and there isn’t any credentials in the keychain. When the user clicks on the login button the keyboard that is presented is dismissed. The code is:

- (IBAction) loginClick: (UIButton *) sender
{
    if ([username isFirstResponder]){
        [username resignFirstResponder];
    }

    if ([password isFirstResponder]){
        [password resignFirstResponder];
    }

    [RKObjectManager sharedManager].client.username = username.text;
    [RKObjectManager sharedManager].client.password = password.text;
    [progressLock lock]; 
    [progressLock unlockWithCondition:0];
    [HUD showWhileExecuting:@selector(myTask) onTarget:self withObject:nil animated:YES];
    [[RKObjectManager sharedManager] loadObjectsAtResourcePath:@"/account/verify.json" objectClass:[Login class] delegate: self];
}

Now inside the app there is an options button. When this is click it will present a modalViewController which has a logout button in it. Clicking on this logout button will present the LoginViewController again. The code is:

- (IBAction) logout:(id)sender
{
    NSUserDefaults *standardDefaults = [NSUserDefaults standardUserDefaults];
    NSString * username = [standardDefaults stringForKey:@"kApplicationUserNameKey"]; 
    NSError * error = nil;

    [standardDefaults removeObjectForKey:@"kApplicationUserNameKey"];
    [SFHFKeychainUtils deleteItemForUsername:username andServiceName:@"convore" error:&error];
    LoginViewController* lvc = [[LoginViewController alloc] init];
    lvc.delegate = self;
    [self.mgvc.groups removeAllObjects];
    [self.mgvc.table reloadData];

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

    [self presentModalViewController:lvc animated:YES];
    [lvc release];  
}

What’s weird is that I can’t seem to dismiss the keyboard when I click on the login button this time. Why is this? Is it because as of now I am displaying the LoginViewController from a modalviewcontroller? How do I solve this weird issue?

Answer 1

I don’t know whether the fact that you can’t dismiss the keyboard is due to presenting the login in a modal view, nor do I see anything evidently wrong with your code.

I would suggest you to change your flow and make:

1. the logout button dismiss your first modal view and,

2. your login view be displayed as a normal view, once the modal view disappears.

Explicitly, you can do 2 either by one of several means:

1. trying and pushing the login view controller on your navigation controller (if you have one);

2. selecting it in a tab bar controller (if you use one);

3. your modal view is shown above a view; when the modal is dismissed, that view appears again, and so the viewWillAppear selector of its view controller is called; that’s the place where you can check if you are logged in or out and show the login, if necessary; if you don’t know how to detect if your are in or out, you can always set a flag in the view controller when you dismiss the logout modal view.

   1. (after reading your comment: modal view is not full screen, so viewWillAppear is not called: you can either send viewWillAppear yourself, or send a different, custom message to your superordinate view controller so that it knows that the login view should be displayed (and possibly refresh the view).

   2. EDIT: try something like this (this requires that you call your own selector, not viewWillAppear):

      [baseNonModalViewController performSelector:@selector(yourSelector) withObject:nil afterDelay:0.0];

Executing performSelector with a 0.0 delay, has only the effect of scheduling yourSelector for execution on the main loop. This way, first the modal will be completely dismissed, then the login view will be displayed.