Please allow ads on our site
LoginAngularJS : How to watch service variables?
General Tech Bugs & Fixes 3 years ago
User submissions are the sole responsibility of contributors, with TuteeHUB disclaiming liability for accuracy, copyrights, or consequences of use; content is for informational purposes only and not professional advice.
Answers (3)
In order for the controller to detect when aService.foo is updated I have cobbled together this pattern where I add aService to the controller's $scope and then use $scope.$watch():
function FooCtrl($scope, aService) {
$scope.aService = aService;
$scope.foo = aService.foo;
$scope.$watch('aService.foo', function (newVal, oldVal, scope) {
if(newVal) {
scope.foo = newVal;
}
});
}This feels long-handed, and I've been repeating it in every controller that uses the service's variables. Is there a better way to accomplish watching shared variables?
manpreet 3 years ago
factory('aService', function() {
var observerCallbacks = [];
//register an observer
this.registerObserverCallback = function(callback){
observerCallbacks.push(callback);
};
//call this when you know 'foo' has been changed
var notifyObservers = function(){
angular.forEach(observerCallbacks, function(callback){
callback();
});
};
//example of when you may want to notify observers
this.foo = someNgResource.query().$then(function(){
notifyObservers();
});
});manpreet 3 years ago
factory('aService', function() {
var observerCallbacks = [];
//register an observer
this.registerObserverCallback = function(callback){
observerCallbacks.push(callback);
};
//call this when you know 'foo' has been changed
var notifyObservers = function(){
angular.forEach(observerCallbacks, function(callback){
callback();
});
};
//example of when you may want to notify observers
this.foo = someNgResource.query().$then(function(){
notifyObservers();
});
});No matter what stage you're at in your education or career, TuteeHUB will help you reach the next level that you're aiming for. Simply,Choose a subject/topic and get started in self-paced practice sessions to improve your knowledge and scores.
Similar Forum
Explore Other Libraries
Online Exams
Question Bank
Career News
Feeds
Full Forms
Dictionary
Interview Question
Gigs
Quotes
Lyrics
Videos
Courses
Blogs
Tutorials
Forum
Educators
Corporates
Tools
manpreet![Tuteehub forum best answer]()
Best Answer
3 years ago
I have a service, say:
And I would like to use
footo control a list that is rendered in HTML: