angularjs - Update Angular View dynamically when MongoDB collection length changes -

i wondering how angular watches database collection changes in mongo db. have variable tracking number of items in mongodb collection , front end view interpolate number whenever new item added collection front end. possible?

example:

var item = $resource('/api/items'),     allitems = item.query(function(results) {         return results;     });  $scope.alltodos = allitems.length; 

front end:

<p ng-show="alltodos > 0">total items: {{alltodos}}</p> 

let's assume had way of adding items via form on front end, submitting them database. how {{alltodos}} number dynamically increase (++) when add new item? in backbone.js, know there collection watch events, ie:

var collection = backbone.collection.extend({     //code... }),     c1         = new collection();  c1.bind("add", function() {     //do when add collection }); 

is possible angular? i'm sure is, please excuse green-ness. thanks!

$resource.query returns empty object immediately. allitems not expect be. once operation complete allitems populated data. there no need return callback

one way set alltodos inside callback:

item.query(function(results) {         $scope.alltodos = results.length;     }); 

or eliminate variable alltodos, make items visible in template (should part of controller's $scope).

var item = $resource('/api/items'); $scope.allitems = item.query(); 

and in html

<p ng-show="allitems.length > 0">total items: {{allitems.length}}</p>