angularjs - $on('value...) gives me "undefined is not a function" in angularfire -



angularjs - $on('value...) gives me "undefined is not a function" in angularfire -

i have started utilize angularjs , next tutorial angularjs angularfire. in tutorial there section larn how utilize child_added

angular.module('firebaseapp').service('messageservice', function(fburl, $q, $firebase) { var messageref = new firebase(fburl).child('messages'); var firemessage = $firebase(messageref).$asarray(); homecoming { childadded: function childadded(limitnumber, cb) { firemessage.$on('child_added', function(snapshot){ console.log(snapshot); var val = snapshot.val(); cb.call(this,{ user: val.user, text: val.text, name: snapshot.name() }); }); },

and main controller :

messageservice.childadded(5, function(addedchild){ $timeout(function() { $scope.messages.push(addedchild); }); });

when utilize code, chrome developer tools giving error :

typeerror: undefined not function

adressing .$on in messageservice , .childadded in controller.

this video tutorial , can see him working this. checked many answers not find way. best shot guess different versions of angularjs , angularfire. did not help me either. can help me solve it?

thank in advance.

i thought i'd offer bit of clarity on topic taking tutorial on tutsplus. first, should pay attending versions of firebase , angularfire using, compared instructor using. might seem obvious, there many out there fail realize it. whenever watching tutorial, should check version of bundle using. world of software moves fast, , up-to-date tutorials luxury.

pay attending bower.json file in project. note version of next lines: "firebase": "~2.0.4", "angularfire": "~0.9.0"

you can see here version of dependencies used. chances are, me, , version differ find in teacher's version. instructor offers source files on course of study main page. download files, should titled sourcefiles_rtwebappangularfirebase.zip. 1 time downloaded, open it, , see list of packaged zip files contained in file called firebase source. find lesson-16-angularfire.zip, , open it. folder titled "firebase" should provided, , there find instructor's app created during tutorial. check out bower.json file, , check against have. according found, both versions of firebase , angularfire vastly different. means 1 thing: have reading do.

go here , check out releases of angularfire: https://github.com/firebase/angularfire/releases

scroll down, , read release notes of v0.8.0. of import note found here.

$on() , $off() no longer exist. similar functionality can obtained $watch() should discouraged trying manually manage server events (manipulation should done info transformations through $extendfactory() instead).

obviously now, understand can't follow blindly in instructor's footsteps. have seek mimicking app's functionality. reading posted above, can utilize $watch obtain similar functionality. however, tried create work, , functionality $watch delivers not functionality trying achieve. ideally, should synchronize our empty messages array $scope.messages $firebase(messageref).$asarray(). wouldn't fun though.

the route took this: looked @ cb.call() doing, following

messageservice.childadded(function(addedchild) { $scope.messages.push(addedchild); });

this phone call function pushes object created cherry picked values obtained snapshot returned 'child_added' event. real leverage here snapshot, provided $firebase module firebase.on(). if read docs "child_added" event, says

this event triggered 1 time each initial kid @ location, , triggered 1 time again every time new kid added. datasnapshot passed callback reflect info relevant child

the datasnapshot returned every "initial" kid @ location, populates list of messages. means can alter this:

firemessage.$on('child_added', function(snapshot){ console.log(snapshot); var val = snapshot.val(); cb.call(this,{ user: val.user, text: val.text, name: snapshot.name() }); });

back this:

messageref.on('child_added', function(snapshot) { var val = snapshot.val(); cb.call(this, user: val.user, text: val.text, name: snapshot.key() }); });

the messages should populate 1 time again on front end page. code should stable plenty follow instructor during remainder of refactor lesson.

angularjs angularfire

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