Update ng-options hosted by a directive - angularjs

Question

I have a custom directive that displays a dropdownlist.
Is it possible to dynamically re-populate the ng-options from a datasource that comes from the controller that hosts the directive.
The datasource itself comes from a service.
Currently it works well from the initial array passed to the directive, but when I add new data (from the controller/service to this array I would like to update the item list.
Any help?
EDIT :
This is how I use my directive.
<select-item-obj-from-array datasource="ctrl.ActivityAddresses" ng-model="form.Activity.AddressID" name="AddressID" value="AddressID" label="City" .... />
My directive looks like:
app.directive('selectItemObjFromArray', function () {
return {
restrict: 'E',
replace: true,
template: function (element, attrs) {
var tpl = '';
tpl += "<div><div class=\"form-group clearfix\" >";
tpl += '<label for="' + attrs.name + '" class="col-lg-3 control-label">' + attrs.label + '</label>';
tpl += '<div class="col-lg-9">';
tpl += '<select ng-disabled="ngDisabled" name="' + attrs.name + '" ng-model="ngModel" chosen="datasource" ng-options="c.Name for c in datasource"></select>';
tpl += '</div>';
tpl += '</div>';
tpl += '</div>';
return tpl;
},
scope: {
ngModel: "=",
datasource: "="
},
link: function (scope, elem, attrs) {
var select = elem.find("select").eq(0);
select.chosen();
scope.$watch(function () {
return select[0].length;
},
function (newvalue, oldvalue) {
if (newvalue !== oldvalue) {
select.trigger("chosen:updated");
}
});
scope.$watch(attrs.ngModel, function () {
select.trigger('chosen:updated');
});
}
};
});
if my controller/service updated the ctrl.ActivityAddresses I don't know how to "reinvoke" the directive to update the dropdownlist..

Answer 1

You can broadcast from your service like this:
var broadcast = function() {
$rootScope.$broadcast('items.update');
};
Assuming that items is an array.
Then you can catch the broadcast in your controller or directive:
$scope.$on('items.update', function (event) {
//Do whatever you want with the items.
});
I think this is what you want? You don't need to change the ng-options directive for this.