Keyboard hide in iPad don't work

I have many views and the problem appears in all of them. I have 'n' UITextField's in a UIView, I implement the UITextFieldDelegate method to hide the keyboard when the user press the "Done" button like this:

- (BOOL)textFieldShouldReturn:(UITextField *)textField {
    [textField resign开发者_C百科FirstResponder];
    return YES;
}

Nothing special. The problem is that doesn't work. The method executes without problem but the keyboard doesn't hide.

Any help?

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The problem was that the view where the field was display was deployed as UIModalPresentationFormSheet, change it to UIModalPresentationPageSheet fix the problem.