How does AngularJS return a value from async call?

Question

Watch this video,

https://www.youtube.com/watch?v=IRelx4-ISbs

You'll find that the code has a line wrote this:

$scope.twitterResult = $scope.twitter.get({q:$scope.searchTerm});

This is a litter quirk: the 'get' method of 'twitter' is obviously a async function, how does it return a value to $scope.twitterResult???

jsFiddle(Can't work cause the twitter API has changed):

http://jsfiddle.net/johnlindquist/qmNvq/

Related: stackoverflow.com/q/15464273/497356

Andrew Whitaker
– Andrew Whitaker

2013-11-29 03:10:28 +00:00
Commented Nov 29, 2013 at 3:10 — Andrew Whitaker
– Andrew Whitaker, Commented Nov 29, 2013 at 3:10

iKBAHT · Accepted Answer · 2013-11-29 03:30:02Z

0

This code $scope.twitter.get({q:$scope.searchTerm}); return defer object. Angular view arranged so that view will be update when defer object resolve. It's just a convenience.

answered Nov 29, 2013 at 3:30

iKBAHT

7226 silver badges20 bronze badges

Sign up to request clarification or add additional context in comments.

2 Comments

Xieranmaya Over a year ago

But how does the deferred object knows which variable should it change? Or the deferred object can change itself?

iKBAHT Over a year ago

When Angular encounters a promise inside the view, it automatically sets up a success callback and substitutes the promise for the resulting value once it has been resolved. Using promises directly on the view is a feature of AngularJS that many people are unaware of, but it opens up a lot of opportunities for making our controllers as lean as possible. Example: plnkr.co/edit/pL4lF9JYXZ7EVJNv7PJK?p=preview

Ramesh Rajendran · Accepted Answer · 2013-11-29 08:26:40Z

0

$scope.twitterResult = $scope.twitter.get({q:$scope.searchTerm});

Your code is good for only angular binding.

But if you need to get data on run time, you need to write this below format.

If $scope.twitter is a URL,Then write it

$http.get($scope.twitter, {q:$scope.searchTerm}).success(function (response) {
$scope.twitterResult=response;
}

$http is must defined in contoller

answered Nov 29, 2013 at 8:26

Ramesh Rajendran

38.9k49 gold badges159 silver badges241 bronze badges

Collectives™ on Stack Overflow

How does AngularJS return a value from async call?

2 Answers 2

2 Comments

Comments

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

2 Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Linked

Related