title: Control selection in UITextView
body: <p>I do not want the user to be able to select the first few characters of my <code>UITextView</code>. I have tried subclassing it and noticed methods such as <code>-setSelectedRange:</code> and <code>-setSelectedTextRange:</code>. Both are called at different times but it seems like it's the latter that I need.</p>
  
  <p>The <code>-setSelectedTextRange:</code> method takes a <code>UITextRange</code> object, which has a <code>UITextPosition</code> property called "start". This sounds like what I want but I cannot write to it, and there are no classes for this object.</p>
  
  <p>Does anyone have any ideas on how I can do this? FWIW, I'm trying to replicate what Facebook have on their "Check-In" view on their iPhone app.</p>
  
  <p>Thanks in advance!</p>