I am developing an angularjs app as a part of my angularjs learning. I have controllers and from there I am calling service layers.
leagueManager.service("teamsService", function($http){
var teams = {};
$http.get('data/teams.json').then(function(data) {
teams = data;
});
this.getTeams = function(){
return teams;
};
});
I noticed that because of the asynchronous nature of $http.get.then stuff, the data is not retrieved immediately and hence I would not get the "teams" when I would call getTeams() from the controller (teamsController), I would get nothing.
Any idea how do I resolve this?
Second Attempt: After reading about deferred and promises on angular as suggested by the post below, I tried following but it still has no effect. My variable teams is not being populates as I want and they are populated afterwards and that is not helping in my UI:
My controller teamsController.js
leagueManager.controller('teamsController', function($scope, $location, teamsService, $routeParams){
//init function to initialize data when controller is called everytime.
var init = function(){
$scope.teams = [];
var promise = teamsService.getTeams();
promise.then(
function(data){
console.log("teams after promise:="+data);
$scope.teams = data;
}
,function(reason)
{
alert('Failed: ' + reason);
}
);
console.log("teams in the scope:="+$scope.teams);
};
init();
});
And here is my ServiceLayer teamsService.js
leagueManager.service("teamsService", function($http, $q){
this.getTeams = function(){
var deferred = $q.defer();
var url = 'data/teams.json';
$http.get(url).success(function(data, status) {
// Some extra manipulation on data if you want...
deferred.resolve(data);
}).error(function(data, status) {
deferred.reject(data);
});
return deferred.promise;
}
});
Can you or someone help me what I am doing wrong? This is what is printed in the browser console upon execution:
teams in the scope:= teamsController.js:27
teams after promise:=[object Object],[object Object],[object Object],[object Object],[object Object]
This simply shows that I do get the json object but not at the time I want. For some reason this deffered/promise thing had no impact.
PLEASE HELP THIS NEW ANGULAR ENTHUSIAST
Yeah you will need to use a promise interface. So instead of returning a teams object, directly you'll have to return a promise:
Promise Resources:
In the service:
leagueManager.service("teamsService", function($http){
var deferred = $q.defer();
$http.get('data/teams.json').then(function(data) {
deferred.resolve(data);
});
this.getTeams = function(){
return deferred.promise;
};
});
Then in the controller:
$scope.team = {};
var promise = teamsService.getTeams();
promise.then(function(data) {
$scope.teams = data;
});