title: Change class in angularjs through controller
body: <p>Please help me to change the class of input[type=button] dynamically using angularjs and controller.</p>
  
  <p><div class="snippet" data-lang="js" data-hide="false">
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  <pre class="snippet-code-js lang-js prettyprint-override"><code>app.controller('anodekeypadcntrl',function($scope){
   
   
   $scope.clickTwentyFour = function(event){
     In this function I need to highlight the button (adding the .active class to it) 
   };
                               
  });</code></pre>
  <pre class="snippet-code-html lang-html prettyprint-override"><code>&lt;div class="keypadcontainer" ng-controller="anodekeypadcntrl as child"&gt;
    ------
    &lt;input type="button" value="24" id="twentyFour" class="twentyfour anodeKeypadButton"
   ng-click="clickTwentyFour($event)" /&gt;
    -------------
  &lt;/div&gt;</code></pre>
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  </div>
  </p>