When I give click to the button "Done" with the keyboard open, it does not do the action if not that hidden the keyboard, what could be?
Not 100% sure what you are asking. Can you clarify your question, perhaps with a code example of what you are trying to do?
As a guess, do you want to hide the keyboard when "Done" is pressed? If so you want to call ResignFirstResponder on the text field, e.g.:
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