Angular: Empty Fiddle
http://angularjs.org/
HTML
<script src="https://code.angularjs.org/1.5.2/angular.js"></script>
<div ng-controller="MyCtrl">
<div ng-repeat="message in messages" ng-class="{'sent': userId == message.id, 'received': userId != message.id}">
<div class="message1" ng-if="message.id !== messages[$index-1].id">
{{message.name}}
</div>
</div>
</div>
JavaScript
var myApp = angular.module('myApp',[]);
//myApp.directive('myDirective', function() {});
myApp.controller('MyCtrl', function MyCtrl($scope) {
$scope.messages = [{
id : 11,
name : 'name11'
},{
id : 11,
name : 'name12'
},{
id : 13,
name : 'name13'
}];
});