AngularJS Example:

by Ztyx

HTML

<div ng-app="telavox.test">
    <div data-ng-controller="MyTestController">
        <p class="error" data-ng-show="error" data-ng-bind="error">
        </p>
        <p data-ng-repeat="item in mylist" data-ng-bind="item">
        </p>
    </div>
</div>

CSS

</style> <!-- Ugly Hack due to jsFiddle issue: http://goo.gl/BUfGZ --> 
<link rel="stylesheet" href="http://twitter.github.com/bootstrap/assets/css/bootstrap.css">
<script src="https://ajax.googleapis.com/ajax/libs/angularjs/1.0.6/angular.min.js"></script>
<style>
.error {
    color: red;
}
}

JavaScript

angular.module('telavox.test', [])
.factory('MySimulatedSlowHTTPService', function($q, $timeout) {
    var deferred = $q.defer();
    $timeout(function() {
        // Simulated slow fetch from an HTTP server
        deferred.reject("Could not fetch the list :-(")
    }, 3000);
    return deferred.promise;
})
.controller('MyTestController', function($scope, MySimulatedSlowHTTPService) {
    MySimulatedSlowHTTPService.then(function(mylist) {
        $scope.mylist = mylist;
    }, function(error) {
        $scope.error = error;
        $scope.mylist = [];
    });
});