title: Format UITextField for dollar input from user in swift
body: <p>I am trying to get a better grasp of delegates and I am trying to create a dollar sign field that begins with the text $0.00, and then fills in the dollar figure as digits are added. For example, typing 4-2-7-5 would produce $0.00, $0.04, $0.42, $4.27, $42.75.</p>
  
  <p>I have created a UITextField and a delegate file for this behavior. I have no idea how to proceed and I am a complete noob in this concept. I found a thread that does explore this concept, but the thread is far more advanced and I don't understand the syntax being used. That question is at: <a href="https://stackoverflow.com/questions/21078572/format-a-uitextfield-for-currency">Format a UITextField for currency</a></p>
  
  <p>I really want to know how to make this happen, but more importantly WHY it works. </p>