iPad keyboard will not dismiss if modal ViewContro

Question

Note:

See accepted answer (not top voted one) for solution as of iOS 4.3.

This question is about a behavior discovered in the iPad keyboard, where it refuses to be dismissed if shown in a modal dialog with a navigation controller.

Basically, if I present the navigation controller with the following line as below:

navigationController.modalPresentationStyle = UIModalPresentationFormSheet;

The keyboard refuses to be dismissed. If I comment out this line, the keyboard goes away fine.

...

I've got two textFields, username and password; username has a Next button and password has a Done button. The keyboard won't go away if I present this in a modal navigation controller.

WORKS

broken *b = [[broken alloc] initWithNibName:@"broken" bundle:nil];
[self.view addSubview:b.view];

DOES NOT WORK

broken *b = [[broken alloc] initWithNibName:@"broken" bundle:nil];
UINavigationController *navigationController = 
[[UINavigationController alloc]
 initWithRootViewController:b];
navigationController.modalPresentationStyle = UIModalPresentationFormSheet;
navigationController.modalTransitionStyle = UIModalTransitionStyleFlipHorizontal;
[self presentModalViewController:navigationController animated:YES];
[navigationController release];
[b release];

If I remove the navigation controller part and present 'b' as a modal view controller by itself, it works. Is the navigation controller the problem?

WORKS

broken *b = [[broken alloc] initWithNibName:@"broken" bundle:nil];
b.modalTransitionStyle = UIModalTransitionStyleFlipHorizontal;
[self presentModalViewController:b animated:YES];
[b release];

WORKS

broken *b = [[broken alloc] initWithNibName:@"broken" bundle:nil];
UINavigationController *navigationController = 
    [[UINavigationController alloc]
         initWithRootViewController:b];
[self presentModalViewController:navigationController animated:YES];
[navigationController release];
[b release];

Answer 1

I found that disablesAutomaticKeyboardDismissal and adding a disablesAutomaticKeyboardDismissal function didn't work for my UITextField in a modal dialog.

The onscreen keyboard just wouldn't go away.

My solution was to disable all text-input controls in my dialog, then re-enable the relevant ones a fraction of a second later.

It seems as though when iOS sees that none of the UITextField controls are enabled, then it does get rid of the keyboard.