StackOverflow_24208265: watch-not-updating-in-ng-repeat

Illustration of answer to http://stackoverflow.com/questions/24208265/watch-not-updating-in-ng-repeat.

by ExpertSystem

HTML

<script src="http://code.angularjs.org/1.2.16/angular.min.js"></script>
<div ng-controller="myCtrl">
    Unit price:
    <input type="number" ng-model="unit_price" />
    <br />
    Quantity:
    <input type="number" ng-model="quantity" />
    <hr />
    Total: {{total}}
</div>

JavaScript

var app = angular.module('myApp', []);
app.controller('myCtrl', function ($scope) {
    $scope.unit_price = 0;
    $scope.quantity   = 0;

    $scope.$watchCollection('[unit_price, quantity]', function(newValues) {
        $scope.total = $scope.unit_price * $scope.quantity;
    });
});