Determine which button is selected on button-bar

ionic-v1
1

Is there a way to determine which button is selected/active on button-bar such as the example below?

<div class="button-bar">
  <a class="button">First</a>
  <a class="button">Second</a>
  <a class="button">Third</a>
</div>
2

depends on what you want to do?
something like this works:

<div class="button-bar">
  <a class="button" ng-click="first()">First</a>
  <a class="button" ng-click="second()">Second</a>
  <a class="button" ng-click="third()">Third</a>
</div>