title: NSTextField and controlTextDidEndEditing
body: <p>I have a class 'EditingField' extending the NSTextField. The textfields are variables in my AppDelegate.</p>
  
  <p>I wish to do something after the user has ended editing the textfield. Apparently i am to use the <code>controlTextDidEndEditing</code> or <code>textFieldDidEndEditing</code>. Which one am i to use?</p>
  
  <p>Furthermore where exactly am i to implement the methods and how do i set a delegate if that is required?</p>