Disable Ionic button bar in HTML Application

Dear All,

I am using Ionic button-bar in my HTML5 mobile application. The button-bar has 2 buttons (Accept and Reject). When The user clicks on Accept (or Reject) the entire button-bar should be disabled so that no new selection can be made.
Javascript:

document.getElementById("hoAccept").disabled = true;//disable accept
document.getElementById("hoReject").disabled = true;//disable reject

HTML:

<div class="button-bar">
      <a id="hoAccept" class="button button-small button-dark" onclick="Response('accept')">Accept</a>
      <a id="hoReject" class="button button-small button-dark" onclick="Response('reject')">Reject</a>
</div>

So whenever the control goes into Response() the bar should be disabled. However the same is not happening. I also tried giving id to the div and disable the div itself; but it did not work. May be there is a different technique to disable Ionic button-bar?
Can any one please provide a solution to it?
Links already referred: