How to architect an Ember.js application - ember.js

It's been difficult to keep up with the evolution of Ember JS as its approached (and reached!) version 1.0.0. Tutorials and documentation have come and gone, leading to a lot of confusion about best practices and the intent of the original developers.
My question is exactly that: What are the best practices for Ember JS? Are there any updated tutorials or working samples showing how Ember JS is intended to be used? Code samples would be great!
Thanks to everyone, especially the Ember JS devs!

Mike Grassotti's Minimum Viable Ember.js QuickStart Guide
This quickstart guide should get you from zero to slightly-more-than-zero in a couple of minutes. When done, you should feel somewhat confident that ember.js actually works and hopefully will be interested enough to learn more.
WARNING: Don't just try this guide then think ember-sucks cause "I could write that quickstart-guide better in jQuery or Fortran" or whatever. I am not trying to sell you on ember or anything, this guide is little more than a hello-world.
Step 0 - Check out jsFiddle
this jsFiddle has all the code from this answer
Step 1 - Include ember.js and other required libraries
Ember.js requires both jQuery and Handlebars. Be sure those libraries are loaded before ember.js:
<script type='text/javascript' src='http://code.jquery.com/jquery-1.9.1.js'></script>
<script type='text/javascript' src="http://cdnjs.cloudflare.com/ajax/libs/handlebars.js/1.0.0-rc.3/handlebars.js"></script>
<script type='text/javascript' src="http://cdnjs.cloudflare.com/ajax/libs/ember.js/1.0.0-rc.1/ember.js"></script>
Step 2 - Describe your application's user interface using one or more handlebars templates
By default ember will replace body of your html page using content of one or more handlbars templates. Someday these templates will be in separate .hbs files assembled by sprockets or maybe grunt.js. For now we will keep everything in one file and use script tags.
First, let's add a single application template:
<script type="text/x-handlebars" data-template-name="application">
<div class="container">
<h1>Ember.js is easy?<small> Minimum Viable Ember.js QuickStart Guide</small></h1>
<p>{{message}}</p>
</div>
</script>
Step 3 - Initialize your ember application
Just add another script block with App = Ember.Application.create({}); to load ember.js and initialize your application.
<script type='text/javascript'>
App = Ember.Application.create({});
</script>
That's all you need to create a basic ember application, but it's not very interesting.
Step 4: Add a controller
Ember evaluates each handlebars templates in the context of a controller. So application template has a matching ApplicationController. Ember creates is automatically if you don't define one, but here let's customize it to add a message property.
<script type='text/javascript'>
App.ApplicationController = Ember.Controller.extend({
message: 'This is the application template'
});
</script>
Step 5: Define routes + more controllers and templates
Ember router makes it easy to combine templates/controllers into an application.
<script type='text/javascript'>
App.Router.map(function() {
this.route("index", { path: "/" });
this.route("list", { path: "/list" });
});
App.IndexController = Ember.Controller.extend({
message: 'Hello! See how index.hbs is evaluated in the context of IndexController'
});
App.ListRoute = Ember.Route.extend({
setupController: function(controller) {
controller.set('content', ['angular.js', 'backbone.js', 'ember.js']);
}
});
</script>
To make this work, we modify our the application template by adding an {{outlet}} helper. Ember router will render appropriate template into the outlet depending on user's route. We will also use the {{linkTo}} helper to add navigation links.
<script type="text/x-handlebars" data-template-name="application">
<div class="container">
<h1>Ember.js is easy?<small> Minimum Viable Ember.js QuickStart Guide</small></h1>
<p>{{message}}</p>
<div class="row">
{{#linkTo index class="span3 btn btn-large btn-block"}}Home{{/linkTo}}
{{#linkTo list class="span3 btn btn-large btn-block"}}List{{/linkTo}}
</div>
{{outlet}}
</div>
</script>
<script type="text/x-handlebars" data-template-name="list">
<h3 class="demo-panel-title">This is the list template</h3>
<ul>
{{#each item in content}}
<li>{{item}}</li>
{{/each}}
</ul>
</script>
<script type="text/x-handlebars" data-template-name="index">
<h3 class="demo-panel-title">This is the index template</h3>
<p>{{message}}</p>
</script>
Done!
A working example of this application is available here.
You can use this jsFiddle as a starting point for your own ember apps
Next Steps...
Read the Ember Guides
Maybe buy the Peepcode screencast
Ask questions here on Stack Overflow or in ember IRC
For reference, my original answer:
My question is for any Ember.js expert, and certainly the respective tutorial authors: When should I use design patterns from one tutorial, and when from the other?
These two tutorials represent best practices at the time they were written. For sure there is something that can be learned from each, both are sadly doomed to become out of date because ember.js is moving very quickly. Of the two, Trek's is far more current.
What components of each are personal preferences, and what components will prove essential as my app matures?
If you are developing a new ember application I would not recommend following the Code Lab approach. It is just too out-of-date to be useful.
In Code Lab's design, Ember seems to be closer to existing within the application (even though it is 100% of his custom JS), whereas Trek's application seems to live more within Ember.
Your comment is bang-on. CodeLab is making taking advantage of core ember components and accessing them from global scope. When it was written (9 months ago) this was pretty common but today best-practice for writing ember applications is much closer to what Trek was doing.
That said, even Trek's tutorial is becoming out-of-date. Components that were required ApplicationView and ApplicationController are now generated by the framework itself.
By far the most current resource is the set of guides published at http://emberjs.com/guides/
- they have been written from the ground up over the last few weeks and reflect the latest (pre-release) version of ember.
I'd also check out trek's wip project here: https://github.com/trek/ember-todos-with-build-tools-tests-and-other-modern-conveniences
EDIT:
#sly7_7 : I'd also give an other example, using ember-data https://github.com/dgeb/ember_data_example

There is an important project that both new and veteran Ember.js developers should take advantage of:
Ember-CLI
While it does require some comfort level with the command line, you can generate a modern Ember project with community recommended best practices in a matter of seconds.
While it is beneficial to setup an Ember.js project the hard way as in Mike Grassotti's answer, you should not be doing that for production code. Especially when we have such a powerful and easy to use project like Ember-CLI to show us the Yehuda approved happy path.

There is 30 minutes fresh screencast made by #tomdale: https://www.youtube.com/watch?v=Ga99hMi7wfY

I would highly recommend using Yeoman and its accompanying ember generator. Out of the box you get all the tools you need to develop, test and prepare an app for production. As an added bonus, you'll be able to split your view templates into multiple files and start with an intelligent directory structure that will facilitate you in creating a maintainable codebase.
I've written a tutorial on getting it up and running in about 5 minutes. Just install node.js and follow along here

The Fire Up Ember - Peepcode screencast is worth a watch.

Also go through this free tutorial titled Let’s Learn Ember from Tuts+ Premium. Its free because its from their free courses series.
This course, as the Tuts guys call it, is divided into fourteen easy to follow chapters.
I hope this helps.
Regards,

I prefer the charcoal yeoman approach. It gives you a ton of stuff out of the box including:
a nice folder architecture using a 'module' approach.
neuter
live reload
minify
uglify
jshint
and more.
and its super easy to setup, just run yo charcoal to create an app then yo charcoal:module myModule to add a new module.
more info here: https://github.com/thomasboyt/charcoal

I've just created a Starter Kit, if you would like to use the latest EmberJS with Ember-Data, with Emblem template engine. All wrapped in Middleman, so you can develop with CoffeeScript. Everything on my GitHub: http://goo.gl/a7kz6y

Although outdated Flame on Ember.js
is still a good tutorial for someone looking at ember for the first time.

I've started building a series of videos that start from before Ember and build towards using Ember in anger in serious use-cases for real-world things.
If you're interested in seeing this hit the light of day (I'm more than happy to eventually put it public if there's interest) you should definitely go over to the post I made and hit "like" (or just comment here, I guess):
http://discuss.emberjs.com/t/making-ember-easier-to-approach-aka-crazy-screencasts-videos-that-will-stick-in-your-mind-for-learning-ember/5284
I'm super keen to make it to help the community flourish, but also to help people learn how to build standard web sites in an easy way.

Related

Sahrethis emberJs

I want to add sharethis in emberjs templates.
After a lot of test i manage to make it work by adding the script tag inside the template itself.
<script type="text/javascript" src="http://platform-api.sharethis.com/js/sharethis.js#property=xxxxxxxxx&product=inline-share-buttons"></script>
Is their a way to do it in a better way ?
I would like to add the script in the page header and to force rerendering of sharethis in the controller of my view after the rendering.
But i was not able to make it work in ember.
Note : i use ember 1.13
If you want a cleaner solution, you can check out this ember component:
https://github.com/webnuts/ember-cli-share-this
It'll add a share-this component which you can use in your templates like so:
{{#share-this}}
<span class='st_facebook_hcount' displayText='Facebook'></span>
<span class='st_twitter_hcount' displayText='Tweet'></span>
{{/share-this}}

ember not working on jsfiddle

For some reason ember won't work in jsfiddle at the moment. And, I mean it won't work for my simple example, it won't work for other fiddles such as this starter kit, or this one, or either of the fiddles in this post.
I've tried this on Chrome and Firefox on two different machines. And, on my example, I've tried a range of CDNs, methods of including the libraries, versions, body declarations and actual code.
I must be doing something dumb because I keep getting different errors depending on which example I look at, which seems to indicate something fundamentally wrong but I assume jsfiddle works (or worked) in general.
Is anyone else seeing the same thing as me?
Apparently, posts with links to jsfiddle must be accompanied by code now? I've seen other posts with jsfiddle links and no code? Isn't this the whole point of jsfiddle? Well, here's the code.
Add the app initialization script:
var App = Ember.Application.create();
and wrap your handlebars in the correct <script> tags:
<script type="text/x-handlebars" data-template-name="application">
....
</script>
Updated JSFiddle

Updating backed array in Ember.js rc1 does not propogate to view

I am trying to upgrade a partially built UI to the latest Ember.js rc1 and it has turned into a very big rewrite job thanks to the dramatically changed API. Most info out there (and here) has been rendered useless. I've had to go through the documentation again several times to get things partially working but there are a lot of loose ends. Here is a biggie. The views do not update like they did under the previous version. I'm missing something that must have to do with rerender, {{outlet}} or something else that I'm not aware of. The ember guides seem to need updates.
The template is very simple:
<script type="text/x-handlebars" data-template-name="index">
<button {{action "addOne"}}>add one</button>
<ul>
{{#each item in controller}}
<li>{{item.title}}</li>
{{/each}}
</ul>
</script>
When clicked, the button adds a new element to the backed array. The console logs show that the array is growing, but the template does not change. Here is a jsfiddle to illustrate how far I've gotten. Can anyone figure out what needs to be added?
I modified your example to highlight the fact when we use arrays in Ember, that we are using Ember arrays (Ember.A() or Em.A() if you want to make explicit this fact). From my understanding, you can use the methods Em.A().addObject and Em.A().removeObject to achieve the basic functionality using the Ember.Object getter and setter methods, (i.e. .get() & .set()) .
In order be properly observed by the Ember application, it is important to use the Ember getters and setters.
A modified version of your fiddle.

archetypal code from Ember's own site not working -- any ideas?

There are several extensive code examples on a tutorial page at the ember web site that are all failing in a specific way. As this is supposed to be archetypal ember code ostensibly to direct newcomers how to code in ember, I am at a loss. Could someone who knows ember have a look at the code. (An example is directly above that bookmark I listed, and includes both the templates and js.
Specifically what's happening is that the main root page template has an outlet 'footer' that's only written to by the subpages, but when you navigate back to the home (root/index) page, that outlet still has the info from the subpages showing, which it shouldn't. The same thing is happening with the template called 'traversal' whose outlet is only written to by the subpages, but that outlet is also still showing info in it when you navigate back to the root.
I did run across a function disconnectOutlet in the API docs, but it says you shouldn't hardly ever have to use it, and its not in the example code. I tried it - evidently not actually in the api anymore.
If you want to run that code above you'll need the following from the ember site:
<link rel="stylesheet" href="css/style.css">
<script src="js/libs/jquery-1.7.2.min.js"></script>
<script src="js/libs/handlebars-1.0.rc.1.js"></script>
<script src="js/libs/ember-1.0.pre.min.js"></script>
As you mentioned, disconnectOutlet was added by this pull request. You can use it to remove an outletView (by name) from a controller. For example, remove myOutletViewName from applicationController when exiting a certain route:
aRoute: Ember.Route.extend({
exit: function(router) {
router.applicationController.disconnectOutlet('myOutletViewName')
}
})
Note that if you use {{outlet}} in your template, without specifying a name, the default name is view so you do:
router.applicationController.disconnectOutlet('view')

Ember.js handling jQuery location changes

Quick question.
I found handling site navigation (not the routing aprt, just a simple nav bar) with ember.js a little complex.
So I thought I will just code this aprt with jQuery, push history into location url and hope that Ember.js will detect this change and the router take action.
Scenario :
1) ember.js will use a DIV for rootElement and the navbar is declared in the body.
<body>
<div id="nav">
<ul><li><a>Item1</a></li></ul>
</div>
<div id="rootEmberApp"></div>
</body>
2) then a jQuery script will be bound to the links (item1) of the nav div and push changes to the URL but preventing default action without stopping the propgation (I didn't want to reload all the scripts). Something like :
$(document).ready(function(){
$("#navigation a").click(function(event){
App.router.location.setURL('/ember/listItems');
event.preventDefault();
});
3) I was hoping that Ember.js will fire at this time and take action.
I didn't succeed.
Is it silly ? Any idea how to do that ?
Thanks a lot.
Update 1 : thanks for the answer. Yes you're right. I was just not fully pleased with the solutions I tried or found about a nav bar. I will look again the todoMVC example and its use of the CollectionView. From a beginner point of view, the CollectionView seems a good way to describe (declare) the View and at the same times it's not easy to read (it's easier when the view is written with pure html and the js is bound to it ala jQuery).
Thanks again
This will probably not be a satisfactory answer, but... this is not the Ember Way. A core concept of Ember routing is that once the app loads, the source of truth is in Javascript. As you move through an Ember app, the router transitions from state to state and the URL is updated as a side effect. You're trying to turn that on it's head. It's not impossible -- you can definitely get what you're trying to do to work. However, I wanted you to know that it goes against the intention the designers had in mind.