title: Remove focus from a text field Objective C Xcode
body: <p>In my app I have a text field, that when clicked, a picker view  appears.
  I want the focus to be removed from the field when I click done on the picker view because currently if I hit done then click the same text field the picker view won't appear again (say if user hits done by accident and wants to edit field again). 
  Please help, thanks </p>