title: get all RadioGroup options ID
body: <blockquote>
    <p>Why is it possible to change the background color but it's not to set
    the new text????</p>
  </blockquote>
  
  <pre><code>RadioGroup allRadioGroups[] = {button1, button2};
  </code></pre>
  
  <blockquote>
    <p>why I can do these ones:</p>
  </blockquote>
  
  <pre><code>allRadioGroups[0].getChildAt(1).setBackgroundColor(Color.parseColor("#216059"));
  
  allRadioGroups[1].getChildAt(3).setEnables(false);
  </code></pre>
  
  <blockquote>
    <p>but I can't do these ones:</p>
  </blockquote>
  
  <pre><code>allRadioGroups[0].getChildAt(1).isChecked();
  
  allRadioGroups[1].getChildAt(3).setText("My Text");
  </code></pre>