Develop Reference

Ember - No Data in hasMany Relationship On Initial Load

ember-cli - 3.20, ember-data - 3.30
I am trying to modify the data in a hasMany relationship in the controller setup but the relationship has no data. However, all the data is there after the page is fully loaded (i.e. in my template/actions, all relationship data is there)
I have a Quiz application with Many-Many relationship with Questions.
models/Quiz.js
import { computed } from '#ember/object';
import DS from 'ember-data';
const { attr, hasMany, Model } = DS;
export default Model.extend({
description: attr('string'),
questions: hasMany('question', {async: true}) //also tried with async false
});
models/Question.js
export default Model.extend({
question: attr('string'),
quizzes: hasMany('quiz', {async: true}) //also tried with async false
});
Go to url '/quiz/1' and Route calls findRecord on quiz
routes/quizzes/quiz.js
import Route from '#ember/routing/route';
export default Route.extend({
model(params) { return this.store.findRecord('quiz', params.quiz_id); }
});
controllers/quizzes/quiz.js
import { computed } from '#ember/object';
import Controller from '#ember/controller';
export default Controller.extend({
quiz: computed.alias('model'),
//also attempted in setupController/afterModel in router
modelChanged: function() {
let quiz = this.get('quiz');
let questions = quiz.get('questions'); //questions has no data
questions.then(questions => {
Promise.all(questions.map(question => {
//modify questions/answers here
}));
});
}.observes('model')
actions: {
getQuestions() {
let questions = this.get('quiz.questions'); //questions now has data
}
})};
I have tried to get the question data in both setupController() and afterModel() with no luck.
Note:
The quizzes are nested routes able to select between each quiz to display. So if you navigate from '/quiz/1' to '/quiz/2' and then back to 'quiz/1', the question data is available in the observer, setupController, afterModel, etc. So, the second time you access a specific quiz, the data is available in setup. (data is always available in template/actions).
Any ideas?

Temporary Workaround:
Use an observer on 'quiz.questions' along with a flag to check if first time hitting observer.
import { computed } from '#ember/object';
import Controller from '#ember/controller';
export default Controller.extend({
quiz: computed.alias('model'),
areAnswersSet: false,
observeQuestions: function() {
let questions = this.get('quiz.questions');
if (!this.areAnswersSet && questions.length !== 0) {
this.toggleProperty('areAnswersSet');
questions.forEach(question => { //modify question });
}
}.observes('quiz.questions.[]')
Drawback: Observer will still get called on every questions change. Only needed on initial load.

There were a few bugs in Ember Data 3.3.0 that were related to relationships. It’s worth upgrading to Ember Data 3.3.1 to see if your issue goes away ...

Content is undefined when trying to work with a record in Ember

I am trying to update a record in the Ember store. When I try to do this, it returns the following error:
Uncaught Error: Assertion Failed: Cannot delegate set('name', test) to the 'content' property of object proxy : its 'content' is undefined.
The controller looks like this:
import Ember from 'ember';
export default Ember.Controller.extend({
model: null,
event: {
name: "test",
id: "adfg8943224xcvsdf"
},
actions: {
editEvent (event) {
var Event = this.store.find('event', event.id);
Event.set('name', event.name);
Event.save()
}
}
});
The route looks like this:
import Ember from 'ember';
export default Ember.Route.extend(AuthenticatedRouteMixin, {
model () {
return {
event: this.store.find('event')
}
},
setupController (controller, model) {
controller.set('model', model);
}
});
The template triggers the action, sending along a object called event, which has properties like name and id. The values of the event object come from the controller and have been set before triggering the editEvent action:
<form {{action 'editEvent' event on="submit"}}>

I believe what is happening is that your model hook is returning a POJO that contains a promise that will resolve. If you want to pass that to your action then you need to do
<form {{action 'editEvent' model.event on="submit"}}>
That being said you should really just return a promise from your model hook so that Ember will wait for your data to load before rendering the template. With the way you have it setup now, if your data takes a long time to load, someone could submit the form before the model is loaded and you'll get an error.
I think you want your route to look like this (no need to override setupController):
import Ember from 'ember';
export default Ember.Route.extend(AuthenticatedRouteMixin, {
model () {
return this.store.find('event');
}
});
Then in your template:
<form {{action 'editEvent' model on="submit"}}>
If you need to load multiple models then you should use Ember.RSVP.hash.
See this answer: EmberJS: How to load multiple models on the same route?
Also, I'm not quite sure what your action is trying to do but you don't need to find the record again. The code you posted for your action doesn't actually do anything. It gets the event and then sets the event's name to its own name.
actions: {
editEvent (event) {
// you already have the event, you passed it in as a parameter
// you don't need to query the store again for it.
var Event = this.store.find('event', event.id);
// This doesn't do anything as it just sets the event.name to itself
Event.set('name', event.name);
Event.save()
}
}
I think you mean to do this:
actions: {
editEvent (event) {
event.set('name', 'updated name');
event.save();
}
}

How to asynchronously load and append data to model on checkbox change of component?

I am currently developing an ember application which has two components.
One component represents a map the other one represents a friendslist.
Both components are placed in the same handlebar template.
What I try to achieve is that a user can check a checkbox in the friendslist component and in the next step his or her posts are loaded asynchronously from facebook (the friend itself was already loaded in the beforeModel hook). Those asynchronously loaded posts should be append to the already existing friend object in the model. Afterwards the map component should be informed about the changes and refresh itself or call a function which will draw points on the map.
At the moment I am trying to set the checked property of a single friend (which would be the same approach as appending the posts but will be easier for now):
// index.hbs
{{map-widget posts=model.posts friends=model.friends}}
{{friends-list checkedFriend='checkedFriend' friends=model.friends}}
// friends-list.hbs (component)
<ul>
{{#each friends as |friend|}}
<li>
{{input type="checkbox" id=friend.facebookID checked=friend.checked change=(action checkedFriend)}} <p>{{friend.name}}</p>
</li>
{{/each}}
</ul>
// friends-list.js (component)
import Ember from 'ember';
export default Ember.Component.extend({
actions: {
checkedFriend: function () {
this.sendAction('checkedFriend');
}
}
});
// index.js (route)
export default Ember.Route.extend(AuthenticatedRouteMixin, {
...
model: function() {
return Ember.RSVP.hash({
posts: this.get('currentUserPosts'),
friends: this.get('friends')
});
},
actions: {
checkedFriend: function () {
// Update just the first friend here to see if the approach works
// Get the friends array from the model
const model = this.controller.get('model');
const friends = model.friends;
// Update the friend
Ember.set(friends[0], 'checked', true);
// Map component receives an update here,
// but "DEPRECATION: You modified (mut model.friends) twice in a single render." warning occurs
this.set('friends', friends);
}
}
})
The current approach works more or less. However, I get a depreciation warning that I modified the model twice in a single render which in my opinion is a sign for a bad design from myside.
What I would like know is how a good approach for my task described above would look like. If I am already on the right way I would be glad if anyone could tell me why this double rendering error appears.
The core problem is how to correctly update the model and how to inform the components especially the component which did not set the action about the changes so that those are refreshed.
Thank you in advance.

You could make a Class - FriendEntry. By calling its constructor you will recieve an instance of FriendEntry. Now you will be modifying instance instead of original record (which indeed is not right).
var FriendEntry = Ember.Object.extend({
init: function() {
this._super(...arguments);
this.set('somethingFriendly', true);
}
});
export default Ember.Controller.extend({
friendsEntries: Ember.computed.map('model.friends', function(friend) {
// Call the constructor
return FriendEntry.create({
friend: friend,
checked: false,
posts: []
})
})
});
Ok so your component would look something like this.
{{friends-list checkedFriend='changeFriendCheckedStatus' entries=friendEntries}}
// friends-list.hbs (component)
<ul>
{{#each entries as |entry|}}
{{input type="checkbox" checked=entry.friend.checked change=(action checkedFriend entry)}} <p>{{entry.friend.name}}</p>
{{/each}}
</ul>
// friends-list.js (component)
import Ember from 'ember';
export default Ember.Component.extend({
actions: {
checkedFriend: function (entry) {
this.sendAction('checkedFriend', entry);
}
}
});
Back to controller
actions: {
changeFriendCheckedStatus(friendEntry) {
ic.ajax.request(API.HOST + '/someUrlForPosts/' + friendEntry.get('id)).then(givenFriendPosts => {
entry.get('posts').pushObjects(givenFriendPosts);
})
}
}
If i understood correctly you have 2 models I friends and posts (DS.belongsTo('friend')). You would need to encapsulate both into friendEntry (friend, posts).
So your map-widget would also look like this {{map-widget friendEntries=friendEntries}}
Instead of querying posts in model you could encapsulate them like this.
friendsEntries: function() {
return DS.PromiseArray.create({
promise: Ember.RSVP.all(this.get('model.friends')).then(friends => {
return friends.map(friend => {
return FriendEntry.create({
friend: friend,
checked: false,
posts: store.query('posts', { friend: friend.get('id') }
});
});
})
});
}.property('model.friends.[]')

How do I call a controller action from an Ember route while doing a transition?

My objective is to display a fancy "loading..." graphic on my page while Ember fetches model data through the Ember route.
This led me to http://emberjs.com/guides/routing/loading-and-error-substates/. That inspired me to create an action on my page's controller which would show the "loading" overlay window in the DOM. For example, here's my controller:
controllers/users.js:
export default Ember.ArrayController.extend({
...
actions: {
displayLoading: function() {
// Show the DOM element that says "Loading..."
},
...
}
});
I'd like to call that while my data is loading, so I then define a route as follows:
routes/users.js:
export default Ember.Route.extend({
model: function( params ) {
return this.store.find('user', params );
},
actions: {
loading: function(transition, originRoute) {
transition.send('displayLoading');
}
}
});
But when I do this, I get this error:
Uncaught Error: Nothing handled the action 'displayLoading'. If you did handle the action, this error can be caused by returning true from an action handler in a controller, causing the action to bubble.
So my question is where can I define this action so that my loading method will be able to call it?
Note that trying this.send('displayLoading') gave me this error:
Can't trigger action 'displayLoading' because your app hasn't finished transitioning into its first route. To trigger an action on destination routes during a transition, you can call .send() on the Transition object passed to the model/beforeModel/afterModel hooks..
Update: I am able to catch this action on the route itself, but then I still can't call the action on my controller.
Update #2: Thanks to #kingpin2k's answer, I've resolved this. For those interested, here is a full solution:
controllers/users.js:
export default Ember.ArrayController.extend( {
actions: {
showLoading: function() {
this.set('isLoading', true);
},
hideLoading: function() {
this.set('isLoading', false);
},
}
});
routers/users.js:
export default Ember.Route.extend({
model: function( params ) {
return this.store.find('user', params );
},
actions: {
loading: function() {
this.controllerFor('users').send('showLoading');
},
didTransition: function() {
this.controllerFor('users').send('hideLoading');
}
}
});
A key insight was that I can set an isLoading property on my controller which determines whether my modal "Loading..." window is showing in the Handlebars template.

use controllerFor, http://emberjs.com/api/classes/Ember.Route.html#method_controllerFor
loading: function(transition, originRoute) {
var controller = this.controllerFor('foo');
controller.send('displayLoading');
}

Emberjs nothing handled this action

Error : Uncaught Error: Nothing handled the action 'rollDice'. If you did handle the action, this error can be caused by returning true from an action handler in a controller, causing the action to bubble.
I made sure that the method in the controller had the same name as the action.
???
HTML portion
<script type="text/x-handlebars">
{{outlet}}
</script>
<script type="text/x-handlebars" id="index">
{{#linkTo "roll"}}Lets roll dice!{{/linkTo}}
</script>
<script type="text/x-handlebars" id="roll">
<p class="centerme">A Dice Roller.</p>
<p> </p>
<p>Click to play!<br/>
<button id="play" {{action 'rollDice'}}>Roll Dice</button>
</p>
<section id="roll-wrap">Dice stuff</section>
<script>
Controller
DiceRoller.RollController = Ember.ObjectController.extend({
var diceModel = this.get('model');
actions: {
rollDice: function () {
var x=[270,1080,1440,810];
var rand1=Math.floor(Math.random()*4);
var rand2=Math.floor(Math.random()*4);
diceModel.set('rotateXvalue',x[rand1]+"deg");
diceModel.set('rotateYvalue',x[rand2]+"deg");
diceModel.save();
}.property('diceModel.rotateXvalue','diceModel.rotateYvalue')
}
});
Routing
DiceRoller.Router.map(function() {
this.resource("roll");
});
DiceRoller.IndexRoute = Ember.Route.extend({
redirect: function(){
this.transitionTo("roll");
}
});
DiceRoller.DiceRoute = Ember.Route.extend({
model: function() {
return this.store.find('Dice');
}
});
Model
DiceRoller.Dice = DS.Model.extend({
rotateXvalue: DS.attr('string'),
rotateYvalue: DS.attr('string')
});
DiceRoller.Dice.FIXTURES = [
{
rotateXvalue: '40deg',
rotateYvalue: '37deg'
}
];
http://jsbin.com/qosujasi/1/
My JS bin, so far it gives me an error about setting the content of an object proxy.

You've named your controller incorrectly. The correct controller for the roll route would be DiceRoller.RollController.
In the RollController, you should get the model inside the roleDice action and you don't need the list of properties. That's for computed properties, not actions.
DiceRoller.RollController = Ember.ObjectController.extend({
actions: {
rollDice: function () {
var diceModel = this.get('model');
var x=[270,1080,1440,810];
var rand1=Math.floor(Math.random()*4);
var rand2=Math.floor(Math.random()*4);
diceModel.set('rotateXvalue',x[rand1]+"deg");
diceModel.set('rotateYvalue',x[rand2]+"deg");
diceModel.save();
}
}
});
Check out this jsBin.
You need to create the model record to be able to set values on it in your route, like this:
DiceRoller.RollRoute = Ember.ObjectController.extend({
model:function() {
return this.store.createRecord('dice');
}
});

I am fresh new to Ember.js and also struggling, but for me it worked to either move actions: {...} from controller to route:
DiceRoller.DiceRoute = Ember.Route.extend({
model: function() {
return this.store.find('Dice');
},
actions: {...} // move actions here
});
OR to use ApplicationController instead of RollController:
DiceRoller.ApplicationController = Ember.ObjectController.extend({
var diceModel = this.get('model');
actions: {
rollDice: function () {
var x=[270,1080,1440,810];
var rand1=Math.floor(Math.random()*4);
var rand2=Math.floor(Math.random()*4);
diceModel.set('rotateXvalue',x[rand1]+"deg");
diceModel.set('rotateYvalue',x[rand2]+"deg");
diceModel.save();
}.property('diceModel.rotateXvalue','diceModel.rotateYvalue')
}
});
Not saying it is the correct way! Just saying it worked for me - still learning ;-)

When you follow Ember official tutorial, and get to the Templates->Actions chapter, you will probably run into this error on first example because this example uses Components that are explained later. I tried adding action to templates/about.hbs and creating component/about.js with action handler, but these two wouldn't work together. Im guessing the trick is to define hbs file in templates/components/ but before that I got the action working by creating
controllers/about.js like this:
import Ember from 'ember';
export default Ember.Controller.extend({
isBody: false,
actions: {
toggleBody() {
console.log("Look at me go!");
this.toggleProperty('isBody');
}
}
});
This is EmberCli environment, v2.0.0 and they say Controllers and Components will merge into one thing soon, so...