title: EXTJS5 Binding Radiogroup
body: <p>There are some days that I'm trying to build a code that allows binding a radiogroup.</p>
  
  <p>However, despite efforts, I have not succeed. </p>
  
  <p>What is missing in my code? </p>
  
  <p>Can you help me, please?</p>
  
  <p>Fiddle:</p>
  
  <p><a href="https://fiddle.sencha.com/#fiddle/bao" rel="nofollow">https://fiddle.sencha.com/#fiddle/bao</a></p>