Mpondomise Mpondomise - 1 month ago 9
AngularJS Question

angularjs firebase user auth service not communicating with the views

I have a service which passes on the parameter

pseudonym
to the evironment. I call on this
pseudonym
in my views, but it doesn't appear at all.

How can I fix this to display the value in my views?


MyUser service:


app.service('MyUser', ['DatabaseRef', 'firebase', function(DatabaseRef, firebase) {
var pseudonym ="";
var userId = firebase.auth().currentUser.uid;

return {
pseudonym: function() {
DatabaseRef.ref('/users/' + userId).once('value')
.then(function (snapshot) {
pseudonym = snapshot.val().pseudonym;
console.log("pseudony: ", pseudonym);
return pseudonym;
});

}
}
}]);


in my console, I see the value for the
pseudonym
. but not in my view html using {{pseudonym}}


and here is the example view controller:


app.controller('ExampleCtrl', ["MyUser",
function (MyUser) {
$scope.pseudonym = MyUser.pseudonym();
}]);

Answer

Return the promise created by the .then method:

app.service('MyUser', ['DatabaseRef', 'firebase', function(DatabaseRef, firebase) {
    //var pseudonym ="";
    var userId = firebase.auth().currentUser.uid;

    return {
        getUserName: function() {
            //return promise
            return (
                DatabaseRef.ref('/users/' + userId).once('value')
                    .then(function onSuccess(snapshot) {
                        let pseudonym = snapshot.val().pseudonym;
                        console.log("pseudony: ", pseudonym);
                        return pseudonym;
                })
            );
        }
    }
}]);

Then extract the value from that promise:

var app = angular.module('app', []);
app.controller('loginController',['$scope', 'MyUser',function($scope, MyUser)
{
    let promise = MyUser.getUserName();
    //Extract data from promise
    promise.then( function onSuccess(pseudonym) {
        $scope.pseudonym  = pseudonym;
        console.log($scope.pseudonym);
    });
}]);

The .then method of an object always returns a promise derived from the value (or promise) returned by the handler function furnished as an argument to that .then method.

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