title: UITextField input validation in iOS 7
body: <p>What is the approppriate way in iOS 7 to deal with text input field validation?
  Is there an alternative to showing the dialog?</p>
  
  <p>I do not have much experience with iOS apps (I'm more of an android fan) and I would like it to be similar to android's:</p>
  
  <pre><code>mEditText.setError("Error string");
  </code></pre>
  
  <p>Closest thing I found is this <a href="https://github.com/ustwo/US2FormValidator">library</a>, but I would like to know if there is something native in iOS (if possible, I would like to avoid using 3rd party libs).</p>
  
  <p>Thanks in advance.</p>