<!doctype html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>AngularJs Demo</title>
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/2.3.0/css/bootstrap.min.css">
<script src="//ajax.googleapis.com/ajax/libs/angularjs/1.3.0-rc.0/angular.min.js"></script>
<script src="demo.js"></script>
</head>
<body ng-app="demo" >
<div ng-controller="DemoController" class="container">
<b> Demo</b>
<div>
Quantità : {{quantita}}
</div>
<br/>
<div>
<button class="btn" ng-click="incrementa()">Incrementa</button>
</div>
</div>
</body>
</html>
angular.module('demo', [])
.controller('DemoController', ['$scope', function($scope) {
$scope.quantita = 1;
$scope.incrementa = function() {
$scope.quantita++;
};
}]);