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<div id="sidebar" class="interface">
<a class="toc_title" href="#">
Backbone.js <span class="version">(0.9.9)</span>
</a>
<ul class="toc_section">
<li>&raquo; <a href="http://github.com/documentcloud/backbone">GitHub Repository</a></li>
<li>&raquo; <a href="docs/backbone.html">Annotated Source</a></li>
</ul>
<a class="toc_title" href="#introduction">
Introduction
</a>
<a class="toc_title" href="#upgrading">
Upgrading
</a>
<a class="toc_title" href="#Events">
Events
</a>
<ul class="toc_section">
<li>– <a href="#Events-on">on</a></li>
<li>– <a href="#Events-off">off</a></li>
<li>– <a href="#Events-trigger">trigger</a></li>
<li>– <a href="#Events-once">once</a></li>
<li>– <a href="#Events-listenTo">listenTo</a></li>
<li>– <a href="#Events-stopListening">stopListening</a></li>
<li>- <a href="#Events-catalog"><b>Catalog of Built-in Events</b></a></li>
</ul>
<a class="toc_title" href="#Model">
Model
</a>
<ul class="toc_section">
<li>– <a href="#Model-extend">extend</a></li>
<li>– <a href="#Model-constructor">constructor / initialize</a></li>
<li>– <a href="#Model-get">get</a></li>
<li>– <a href="#Model-set">set</a></li>
<li>– <a href="#Model-escape">escape</a></li>
<li>– <a href="#Model-has">has</a></li>
<li>– <a href="#Model-unset">unset</a></li>
<li>– <a href="#Model-clear">clear</a></li>
<li>– <a href="#Model-id">id</a></li>
<li>– <a href="#Model-idAttribute">idAttribute</a></li>
<li>– <a href="#Model-cid">cid</a></li>
<li>– <a href="#Model-attributes">attributes</a></li>
<li>– <a href="#Model-changed">changed</a></li>
<li>– <a href="#Model-defaults">defaults</a></li>
<li>– <a href="#Model-toJSON">toJSON</a></li>
<li>– <a href="#Model-sync">sync</a></li>
<li>– <a href="#Model-fetch">fetch</a></li>
<li>– <a href="#Model-save">save</a></li>
<li>– <a href="#Model-destroy">destroy</a></li>
<li>– <a href="#Model-validate">validate</a></li>
<li>– <a href="#Model-url">url</a></li>
<li>– <a href="#Model-urlRoot">urlRoot</a></li>
<li>– <a href="#Model-parse">parse</a></li>
<li>– <a href="#Model-clone">clone</a></li>
<li>– <a href="#Model-isNew">isNew</a></li>
<li>– <a href="#Model-change">change</a></li>
<li>– <a href="#Model-hasChanged">hasChanged</a></li>
<li>– <a href="#Model-changedAttributes">changedAttributes</a></li>
<li>– <a href="#Model-previous">previous</a></li>
<li>– <a href="#Model-previousAttributes">previousAttributes</a></li>
</ul>
<a class="toc_title" href="#Collection">
Collection
</a>
<ul class="toc_section">
<li>– <a href="#Collection-extend">extend</a></li>
<li>– <a href="#Collection-model">model</a></li>
<li>– <a href="#Collection-constructor">constructor / initialize</a></li>
<li>– <a href="#Collection-models">models</a></li>
<li>– <a href="#Collection-toJSON">toJSON</a></li>
<li>– <a href="#Collection-sync">sync</a></li>
<li>– <a href="#Collection-Underscore-Methods"><b>Underscore Methods (28)</b></a></li>
<li>– <a href="#Collection-add">add</a></li>
<li>– <a href="#Collection-remove">remove</a></li>
<li>– <a href="#Collection-reset">reset</a></li>
<li>– <a href="#Collection-update">update</a></li>
<li>– <a href="#Collection-get">get</a></li>
<li>– <a href="#Collection-at">at</a></li>
<li>– <a href="#Collection-push">push</a></li>
<li>– <a href="#Collection-pop">pop</a></li>
<li>– <a href="#Collection-unshift">unshift</a></li>
<li>– <a href="#Collection-shift">shift</a></li>
<li>– <a href="#Collection-length">length</a></li>
<li>– <a href="#Collection-comparator">comparator</a></li>
<li>– <a href="#Collection-sort">sort</a></li>
<li>– <a href="#Collection-pluck">pluck</a></li>
<li>– <a href="#Collection-where">where</a></li>
<li>– <a href="#Collection-url">url</a></li>
<li>– <a href="#Collection-parse">parse</a></li>
<li>– <a href="#Collection-clone">clone</a></li>
<li>– <a href="#Collection-fetch">fetch</a></li>
<li>– <a href="#Collection-create">create</a></li>
</ul>
<a class="toc_title" href="#Router">
Router
</a>
<ul class="toc_section">
<li>– <a href="#Router-extend">extend</a></li>
<li>– <a href="#Router-routes">routes</a></li>
<li>– <a href="#Router-constructor">constructor / initialize</a></li>
<li>– <a href="#Router-route">route</a></li>
<li>– <a href="#Router-navigate">navigate</a></li>
</ul>
<a class="toc_title" href="#History">
History
</a>
<ul class="toc_section">
<li>– <a href="#History-start">start</a></li>
</ul>
<a class="toc_title" href="#Sync">
Sync
</a>
<ul class="toc_section">
<li>– <a href="#Sync">Backbone.sync</a></li>
<li>– <a href="#Sync-ajax">Backbone.ajax</a></li>
<li>– <a href="#Sync-emulateHTTP">Backbone.emulateHTTP</a></li>
<li>– <a href="#Sync-emulateJSON">Backbone.emulateJSON</a></li>
</ul>
<a class="toc_title" href="#View">
View
</a>
<ul class="toc_section">
<li>– <a href="#View-extend">extend</a></li>
<li>– <a href="#View-constructor">constructor / initialize</a></li>
<li>– <a href="#View-el">el</a></li>
<li>– <a href="#View-$el">$el</a></li>
<li>– <a href="#View-setElement">setElement</a></li>
<li>– <a href="#View-attributes">attributes</a></li>
<li>– <a href="#View-dollar">$ (jQuery or Zepto)</a></li>
<li>– <a href="#View-render">render</a></li>
<li>– <a href="#View-remove">remove</a></li>
<li>– <a href="#View-make">make</a></li>
<li>– <a href="#View-delegateEvents">delegateEvents</a></li>
<li>– <a href="#View-undelegateEvents">undelegateEvents</a></li>
</ul>
<a class="toc_title" href="#Utility">
Utility
</a>
<ul class="toc_section">
<li>– <a href="#Utility-Backbone-noConflict">Backbone.noConflict</a></li>
<li>– <a href="#Utility-Backbone-$">Backbone.$</a></li>
</ul>
<a class="toc_title" href="#examples">
Examples
</a>
<ul class="toc_section">
<li>– <a href="#examples-todos">Todos</a></li>
<li>– <a href="#examples-documentcloud">DocumentCloud</a></li>
<li>– <a href="#examples-usa-today">USA Today</a></li>
<li>– <a href="#examples-rdio">Rdio</a></li>
<li>– <a href="#examples-linkedin">LinkedIn Mobile</a></li>
<li>– <a href="#examples-hulu">Hulu</a></li>
<li>– <a href="#examples-flow">Flow</a></li>
<li>– <a href="#examples-gilt">Gilt Groupe</a></li>
<li>– <a href="#examples-newsblur">NewsBlur</a></li>
<li>– <a href="#examples-wordpress">WordPress.com</a></li>
<li>– <a href="#examples-foursquare">Foursquare</a></li>
<li>– <a href="#examples-bitbucket">Bitbucket</a></li>
<li>– <a href="#examples-disqus">Disqus</a></li>
<li>– <a href="#examples-khan-academy">Khan Academy</a></li>
<li>– <a href="#examples-do">Do</a></li>
<li>– <a href="#examples-irccloud">IRCCloud</a></li>
<li>– <a href="#examples-pitchfork">Pitchfork</a></li>
<li>– <a href="#examples-spin">Spin</a></li>
<li>– <a href="#examples-walmart">Walmart Mobile</a></li>
<li>– <a href="#examples-groupon">Groupon Now!</a></li>
<li>– <a href="#examples-basecamp">Basecamp</a></li>
<li>– <a href="#examples-slavery-footprint">Slavery Footprint</a></li>
<li>– <a href="#examples-stripe">Stripe</a></li>
<li>– <a href="#examples-airbnb">Airbnb</a></li>
<li>– <a href="#examples-diaspora">Diaspora</a></li>
<li>– <a href="#examples-soundcloud">SoundCloud Mobile</a></li>
<li>- <a href="#examples-artsy">Art.sy</a></li>
<li>– <a href="#examples-pandora">Pandora</a></li>
<li>– <a href="#examples-inkling">Inkling</a></li>
<li>– <a href="#examples-code-school">Code School</a></li>
<li>– <a href="#examples-cloudapp">CloudApp</a></li>
<li>– <a href="#examples-seatgeek">SeatGeek</a></li>
<li>– <a href="#examples-easel">Easel</a></li>
<li>– <a href="#examples-prose">Prose</a></li>
<li>– <a href="#examples-scrollkit">scroll kit</a></li>
<li>- <a href="#examples-jolicloud">Jolicloud</a></li>
<li>– <a href="#examples-battlefield">Battlefield Play4Free</a></li>
<li>– <a href="#examples-syllabus">Syllabus</a></li>
<li>– <a href="#examples-salon">Salon.io</a></li>
<li>– <a href="#examples-tilemill">TileMill</a></li>
<li>– <a href="#examples-blossom">Blossom</a></li>
<li>– <a href="#examples-decide">Decide</a></li>
<li>– <a href="#examples-trello">Trello</a></li>
<li>– <a href="#examples-tzigla">Tzigla</a></li>
</ul>
<a class="toc_title" href="#faq">
F.A.Q.
</a>
<ul class="toc_section">
<li>– <a href="#FAQ-why-backbone">Why Backbone?</a></li>
<li>– <a href="#FAQ-tim-toady">More Than One Way To Do It</a></li>
<li>– <a href="#FAQ-nested">Nested Models &amp; Collections</a></li>
<li>– <a href="#FAQ-bootstrap">Loading Bootstrapped Models</a></li>
<li>– <a href="#FAQ-extending">Extending Backbone</a></li>
<li>– <a href="#FAQ-mvc">Traditional MVC</a></li>
<li>– <a href="#FAQ-this">Binding "this"</a></li>
<li>– <a href="#FAQ-rails">Working with Rails</a></li>
</ul>
<a class="toc_title" href="#changelog">
Change Log
</a>
</div>
<div class="container">
<p>
<img id="logo" src="docs/images/backbone.png" alt="Backbone.js" />
</p>
<p>
Backbone.js gives structure to web applications
by providing <b>models</b> with key-value binding and custom events,
<b>collections</b> with a rich API of enumerable functions,
<b>views</b> with declarative event handling, and connects it all to your
existing API over a RESTful JSON interface.
</p>
<p>
The project is <a href="http://github.com/documentcloud/backbone/">hosted on GitHub</a>,
and the <a href="docs/backbone.html">annotated source code</a> is available,
as well as an online <a href="test/">test suite</a>,
an <a href="examples/todos/index.html">example application</a>,
a <a href="https://github.com/documentcloud/backbone/wiki/Tutorials%2C-blog-posts-and-example-sites">list of tutorials</a>
and a <a href="#examples">long list of real-world projects</a> that use Backbone.
Backbone is available for use under the <a href="http://github.com/documentcloud/backbone/blob/master/LICENSE">MIT software license</a>.
</p>
<p>
You can report bugs and discuss features on the
<a href="http://github.com/documentcloud/backbone/issues">GitHub issues page</a>,
on Freenode IRC in the <tt>#documentcloud</tt> channel, post questions to the
<a href="https://groups.google.com/forum/#!forum/backbonejs">Google Group</a>,
add pages to the <a href="https://github.com/documentcloud/backbone/wiki">wiki</a>
or send tweets to <a href="http://twitter.com/documentcloud">@documentcloud</a>.
</p>
<p>
<i>
Backbone is an open-source component of
<a href="http://documentcloud.org/">DocumentCloud</a>.
</i>
</p>
<h2 id="downloads">
Downloads &amp; Dependencies
<span style="padding-left: 7px; font-size:11px; font-weight: normal;" class="interface">(Right-click, and use "Save As")</span>
</h2>
<table>
<tr>
<td><a class="punch" href="backbone.js">Development Version (0.9.9)</a></td>
<td class="text"><i>56kb, Full source, lots of comments</i></td>
</tr>
<tr>
<td><a class="punch" href="backbone-min.js">Production Version (0.9.9)</a></td>
<td class="text"><i>6.3kb, Packed and gzipped</i></td>
</tr>
<tr>
<td><a class="punch" href="https://raw.github.com/documentcloud/backbone/master/backbone.js">Edge Version (master)</a></td>
<td>
<i>Unreleased, use at your own risk</i>
<a href="https://travis-ci.org/documentcloud/backbone">
<img width="89" height="13" src="https://travis-ci.org/documentcloud/backbone.png" />
</a>
</td>
</tr>
</table>
<p>
Backbone's only hard dependency is either
<a href="http://underscorejs.org/">Underscore.js</a> <small>( > 1.4.3)</small> or
<a href="http://lodash.com">Lo-Dash</a>.
For RESTful persistence, history support via <a href="#Router">Backbone.Router</a>
and DOM manipulation with <a href="#View">Backbone.View</a>, include
<a href="https://github.com/douglascrockford/JSON-js">json2.js</a>, and either
<a href="http://jquery.com">jQuery</a> <small>( > 1.4.2)</small> or
<a href="http://zeptojs.com/">Zepto</a>.
</p>
<h2 id="introduction">Introduction</h2>
<p>
When working on a web application that involves a lot of JavaScript, one
of the first things you learn is to stop tying your data to the DOM. It's all
too easy to create JavaScript applications that end up as tangled piles of
jQuery selectors and callbacks, all trying frantically to keep data in
sync between the HTML UI, your JavaScript logic, and the database on your
server. For rich client-side applications, a more structured approach
is often helpful.
</p>
<p>
With Backbone, you represent your data as
<a href="#Model">Models</a>, which can be created, validated, destroyed,
and saved to the server. Whenever a UI action causes an attribute of
a model to change, the model triggers a <i>"change"</i> event; all
the <a href="#View">Views</a> that display the model's state can be notified of the
change, so that they are able to respond accordingly, re-rendering themselves with
the new information. In a finished Backbone app, you don't have to write the glue
code that looks into the DOM to find an element with a specific <i>id</i>,
and update the HTML manually
&mdash; when the model changes, the views simply update themselves.
</p>
<p>
If you're new here, and aren't yet quite sure what Backbone is for, start by
browsing the <a href="#examples">list of Backbone-based projects</a>.
</p>
<p>
Many of the examples that follow are runnable. Click the <i>play</i> button
to execute them.
</p>
<h2 id="upgrading">Upgrading to 0.9.9</h2>
<p>
Backbone <b>0.9.9</b> should be considered as a release candidate
for an upcoming <b>1.0</b>. If you're upgrading from a previous version,
be sure to check the
<a href="#changelog">change log</a>. In brief, a few of the larger changes
are:
</p>
<ul>
<li>
Most importantly, Backbone events have two new methods:
<a href="#Events-listenTo">listenTo</a> and
<a href="#Events-stopListening">stopListening</a>. These are an
inversion-of-control flavor of the usual <tt>on</tt> and <tt>off</tt>,
and make it a little easier to clean up <i>all</i> events
that an object is listening to on other objects. When you destroy Views
with <a href="#View-remove">view.remove()</a>, this will now be done
automatically. Note that the usual rules about programming in a garbage
collected language still apply.
</li>
<li>
HTTP <tt>PATCH</tt> support, via <tt>model.save(attrs, {patch: true})</tt>,
if you'd like to send only partial updates to the server.
</li>
<li>
An <a href="#Collection-update">update</a> method was added to Collection,
which should make it easier to perform "smart" syncing updates with the
server, where models are added or removed, and updated attributes are merged
as appropriate. If you were previously using <br />
<tt>collection.fetch({add: true})</tt>,
use <tt>{update: true}</tt> now instead.
</li>
<li>
Backbone events now support <a href="#Events-once"</a>once</a>.
</li>
</ul>
<h2 id="Events">Backbone.Events</h2>
<p>
<b>Events</b> is a module that can be mixed in to any object, giving the
object the ability to bind and trigger custom named events. Events do not
have to be declared before they are bound, and may take passed arguments.
For example:
</p>
<pre class="runnable">
var object = {};
_.extend(object, Backbone.Events);
object.on("alert", function(msg) {
alert("Triggered " + msg);
});
object.trigger("alert", "an event");
</pre>
<p>
For example, to make a handy event dispatcher that can coordinate events
among different areas of your application: <tt>var dispatcher = _.clone(Backbone.Events)</tt>
</p>
<p id="Events-on">
<b class="header">on</b><code>object.on(event, callback, [context])</code><span class="alias">Alias: bind</span>
<br />
Bind a <b>callback</b> function to an object. The callback will be invoked
whenever the <b>event</b> is fired.
If you have a large number of different events on a page, the convention is to use colons to
namespace them: <tt>"poll:start"</tt>, or <tt>"change:selection"</tt>.
The event string may also be a space-delimited list of several events...
</p>
<pre>
book.on("change:title change:author", ...);
</pre>
<p>
To supply a <b>context</b> value for <tt>this</tt> when the callback is invoked,
pass the optional third argument: <tt>model.on('change', this.render, this)</tt>
</p>
<p>
Callbacks bound to the special
<tt>"all"</tt> event will be triggered when any event occurs, and are passed
the name of the event as the first argument. For example, to proxy all events
from one object to another:
</p>
<pre>
proxy.on("all", function(eventName) {
object.trigger(eventName);
});
</pre>
<p>
All Backbone event methods also support an event map syntax, as an alternative
to positional arguments:
</p>
<pre>
book.on({
"change:title": titleView.update,
"change:author": authorPane.update,
"destroy": bookView.remove
});
</pre>
<p id="Events-off">
<b class="header">off</b><code>object.off([event], [callback], [context])</code><span class="alias">Alias: unbind</span>
<br />
Remove a previously-bound <b>callback</b> function from an object. If no
<b>context</b> is specified, all of the versions of the callback with
different contexts will be removed. If no
callback is specified, all callbacks for the <b>event</b> will be
removed. If no event is specified, callbacks for <i>all</i> events
will be removed.
</p>
<pre>
// Removes just the `onChange` callback.
object.off("change", onChange);
// Removes all "change" callbacks.
object.off("change");
// Removes the `onChange` callback for all events.
object.off(null, onChange);
// Removes all callbacks for `context` for all events.
object.off(null, null, context);
// Removes all callbacks on `object`.
object.off();
</pre>
<p>
Note that calling <tt>model.off()</tt>, for example, will indeed remove <i>all</i> events
on the model &mdash; including events that Backbone uses for internal bookkeeping.
</p>
<p id="Events-trigger">
<b class="header">trigger</b><code>object.trigger(event, [*args])</code>
<br />
Trigger callbacks for the given <b>event</b>, or space-delimited list of events.
Subsequent arguments to <b>trigger</b> will be passed along to the
event callbacks.
</p>
<p id="Events-once">
<b class="header">once</b><code>object.once(event, callback, [context])</code>
<br />
Just like <a href="#Events-on">on</a>, but causes the bound callback to only
fire once before being removed. Handy for saying "the next time that X happens, do this".
</p>
<p id="Events-listenTo">
<b class="header">listenTo</b><code>object.listenTo(other, event, callback)</code>
<br />
Tell an <b>object</b> to listen to a particular event on an <b>other</b> object.
The advantage of using this form, instead of <tt>other.on(event, callback)</tt>,
is that <b>listenTo</b> allows the <b>object</b> to keep track of the events,
and they can be removed all at once later on.
</p>
<pre>
view.listenTo(model, 'change', view.render);
</pre>
<p id="Events-stopListening">
<b class="header">stopListening</b><code>object.stopListening([other], [event], [callback])</code>
<br />
Tell an <b>object</b> to stop listening to events. Either call
<b>stopListening</b> with no arguments to have the <b>object</b> remove
all of its <a href="#Events-listenTo">registered</a> callbacks ... or be more
precise by telling it to remove just the events it's listening to on a
specific object, or a specific event, or just a specific callback.
</p>
<pre>
view.stopListening();
view.stopListening(model);
</pre>
<p id="Events-catalog">
<b class="header">Catalog of Events</b>
<br />
Here's the complete list of built-in Backbone events, with arguments.
You're also free to trigger your own events on Models, Collections and
Views as you see fit. The <tt>Backbone</tt> object itself mixes in <tt>Events</tt>,
and can be used to emit any global events that your application needs.
</p>
<ul class="small">
<li><b>"add"</b> (model, collection, options) &mdash; when a model is added to a collection. </li>
<li><b>"remove"</b> (model, collection, options) &mdash; when a model is removed from a collection. </li>
<li><b>"reset"</b> (collection, options) &mdash; when the collection's entire contents have been replaced. </li>
<li><b>"sort"</b> (collection, options) &mdash; when the collection has been re-sorted. </li>
<li><b>"change"</b> (model, options) &mdash; when a model's attributes have changed. </li>
<li><b>"change:[attribute]"</b> (model, value, options) &mdash; when a specific attribute has been updated. </li>
<li><b>"destroy"</b> (model, collection, options) &mdash; when a model is <a href="#Model-destroy">destroyed</a>. </li>
<li><b>"request"</b> (model, xhr, options) &mdash; when a model (or collection) has started a request to the server. </li>
<li><b>"sync"</b> (model, resp, options) &mdash; when a model has been successfully synced with the server. </li>
<li><b>"error"</b> (model, collection) &mdash; when a model's validation fails, or a <a href="#Model-save">save</a> call fails on the server. </li>
<li><b>"route:[name]"</b> (params) &mdash; Fired by the router when a specific route is matched.</li>
<li><b>"route"</b> (router, route, params) &mdash; Fired by history when <i>any</i> route has been matched.</li>
<li><b>"all"</b> &mdash; this special event fires for <i>any</i> triggered event, passing the event name as the first argument. </li>
</ul>
<h2 id="Model">Backbone.Model</h2>
<p>
<b>Models</b> are the heart of any JavaScript application, containing
the interactive data as well as a large part of the logic surrounding it:
conversions, validations, computed properties, and access control. You
extend <b>Backbone.Model</b> with your domain-specific methods, and
<b>Model</b> provides a basic set of functionality for managing changes.
</p>
<p>
The following is a contrived example, but it demonstrates defining a model
with a custom method, setting an attribute, and firing an event keyed
to changes in that specific attribute.
After running this code once, <tt>sidebar</tt> will be
available in your browser's console, so you can play around with it.
</p>
<pre class="runnable">
var Sidebar = Backbone.Model.extend({
promptColor: function() {
var cssColor = prompt("Please enter a CSS color:");
this.set({color: cssColor});
}
});
window.sidebar = new Sidebar;
sidebar.on('change:color', function(model, color) {
$('#sidebar').css({background: color});
});
sidebar.set({color: 'white'});
sidebar.promptColor();
</pre>
<p id="Model-extend">
<b class="header">extend</b><code>Backbone.Model.extend(properties, [classProperties])</code>
<br />
To create a <b>Model</b> class of your own, you extend <b>Backbone.Model</b>
and provide instance <b>properties</b>, as well as optional
<b>classProperties</b> to be attached directly to the constructor function.
</p>
<p>
<b>extend</b> correctly sets up the prototype chain, so subclasses created
with <b>extend</b> can be further extended and subclassed as far as you like.
</p>
<pre>
var Note = Backbone.Model.extend({
initialize: function() { ... },
author: function() { ... },
coordinates: function() { ... },
allowedToEdit: function(account) {
return true;
}
});
var PrivateNote = Note.extend({
allowedToEdit: function(account) {
return account.owns(this);
}
});
</pre>
<p class="warning">
Brief aside on <tt>super</tt>: JavaScript does not provide
a simple way to call super &mdash; the function of the same name defined
higher on the prototype chain. If you override a core function like
<tt>set</tt>, or <tt>save</tt>, and you want to invoke the
parent object's implementation, you'll have to explicitly call it, along these lines:
</p>
<pre>
var Note = Backbone.Model.extend({
set: function(attributes, options) {
Backbone.Model.prototype.set.apply(this, arguments);
...
}
});
</pre>
<p id="Model-constructor">
<b class="header">constructor / initialize</b><code>new Model([attributes], [options])</code>
<br />
When creating an instance of a model, you can pass in the initial values
of the <b>attributes</b>, which will be <a href="#Model-set">set</a> on the
model. If you define an <b>initialize</b> function, it will be invoked when
the model is created.
</p>
<pre>
new Book({
title: "One Thousand and One Nights",
author: "Scheherazade"
});
</pre>
<p>
In rare cases, if you're looking to get fancy,
you may want to override <b>constructor</b>, which allows
you to replace the actual constructor function for your model.
</p>
<p>
If you pass a <tt>{collection: ...}</tt> as the <b>options</b>, the model
gains a <tt>collection</tt> property that will be used to indicate which
collection the model belongs to, and is used to help compute the model's
<a href="#Model-url">url</a>. The <tt>model.collection</tt> property is
otherwise added automatically when you first add a model to a collection.
</p>
<p id="Model-get">
<b class="header">get</b><code>model.get(attribute)</code>
<br />
Get the current value of an attribute from the model. For example:
<tt>note.get("title")</tt>
</p>
<p id="Model-set">
<b class="header">set</b><code>model.set(attributes, [options])</code>
<br />
Set a hash of attributes (one or many) on the model. If any of the attributes
change the model's state, a <tt>"change"</tt> event will be triggered, unless
<tt>{silent: true}</tt> is passed as an option. Change events for specific
attributes are also triggered, and you can bind to those as well, for example:
<tt>change:title</tt>, and <tt>change:content</tt>. You may also pass
individual keys and values.
</p>
<pre>
note.set({title: "March 20", content: "In his eyes she eclipses..."});
book.set("title", "A Scandal in Bohemia");
</pre>
<p>
If the model has a <a href="#Model-validate">validate</a> method,
it will be validated before the attributes are set, no changes will
occur if the validation fails, and <b>set</b> will return <tt>false</tt>.
Otherwise, <b>set</b> returns a reference to the model.
You may also pass an <tt>error</tt>
callback in the options, which will be invoked instead of triggering an
<tt>"error"</tt> event, should validation fail.
</p>
<p>
Passing <tt>{silent: true}</tt> as an option will defer the event.
This is useful when you want to change attributes provisionally or rapidly,
without propagating the change through the rest of the system.
That said, <tt>silent</tt> doesn't mean that the change (and event) won't happen,
it's merely silenced until the next <a href="#Model-change">change</a>.
</p>
<p id="Model-escape">
<b class="header">escape</b><code>model.escape(attribute)</code>
<br />
Similar to <a href="#Model-get">get</a>, but returns the HTML-escaped version
of a model's attribute. If you're interpolating data from the model into
HTML, using <b>escape</b> to retrieve attributes will prevent
<a href="http://en.wikipedia.org/wiki/Cross-site_scripting">XSS</a> attacks.
</p>
<pre class="runnable">
var hacker = new Backbone.Model({
name: "&lt;script&gt;alert('xss')&lt;/script&gt;"
});
alert(hacker.escape('name'));
</pre>
<p id="Model-has">
<b class="header">has</b><code>model.has(attribute)</code>
<br />
Returns <tt>true</tt> if the attribute is set to a non-null or non-undefined
value.
</p>
<pre>
if (note.has("title")) {
...
}
</pre>
<p id="Model-unset">
<b class="header">unset</b><code>model.unset(attribute, [options])</code>
<br />
Remove an attribute by deleting it from the internal attributes hash.
Fires a <tt>"change"</tt> event unless <tt>silent</tt> is passed as an option.
</p>
<p id="Model-clear">
<b class="header">clear</b><code>model.clear([options])</code>
<br />
Removes all attributes from the model, including the <tt>id</tt> attribute. Fires a <tt>"change"</tt> event unless
<tt>silent</tt> is passed as an option.
</p>
<p id="Model-id">
<b class="header">id</b><code>model.id</code>
<br />
A special property of models, the <b>id</b> is an arbitrary string
(integer id or UUID). If you set the <b>id</b> in the
attributes hash, it will be copied onto the model as a direct property.
Models can be retrieved by id from collections, and the id is used to generate
model URLs by default.
</p>
<p id="Model-idAttribute">
<b class="header">idAttribute</b><code>model.idAttribute</code>
<br />
A model's unique identifier is stored under the <tt>id</tt> attribute.
If you're directly communicating with a backend (CouchDB, MongoDB) that uses
a different unique key, you may set a Model's <tt>idAttribute</tt> to
transparently map from that key to <tt>id</tt>.
<pre class="runnable">
var Meal = Backbone.Model.extend({
idAttribute: "_id"
});
var cake = new Meal({ _id: 1, name: "Cake" });
alert("Cake id: " + cake.id);
</pre>
</p>
<p id="Model-cid">
<b class="header">cid</b><code>model.cid</code>
<br />
A special property of models, the <b>cid</b> or client id is a unique identifier
automatically assigned to all models when they're first created. Client ids
are handy when the model has not yet been saved to the server, and does not
yet have its eventual true <b>id</b>, but already needs to be visible in the UI.
Client ids take the form: <tt>c1, c2, c3 ...</tt>
</p>
<p id="Model-attributes">
<b class="header">attributes</b><code>model.attributes</code>
<br />
The <b>attributes</b> property is the internal hash containing the model's
state &mdash; usually (but not necessarily) a form of the JSON object
representing the model data on the server. It's often a straightforward
serialization of a row from the database, but it could also be client-side
computed state.
</p>
<p>
Please use <a href="#Model-set">set</a> to update the <b>attributes</b>
instead of modifying them directly. If you'd like to retrieve and munge a
copy of the model's attributes, use <a href="#Model-toJSON">toJSON</a>
instead.
</p>
<p class="warning">
Due to the fact that <a href="#Events">Events</a> accepts space separated
lists of events, attribute names should not include spaces.
</p>
<p id="Model-changed">
<b class="header">changed</b><code>model.changed</code>
<br />
The <b>changed</b> property is the internal hash containing all the attributes
that have changed since the last <tt>"change"</tt> event was triggered.
Please do not update <b>changed</b> directly. Its state is maintained internally
by <a href="#Model-set">set</a> and <a href="#Model-change">change</a>.
A copy of <b>changed</b> can be acquired from
<a href="#Model-changedAttributes">changedAttributes</a>.
</p>
<p id="Model-defaults">
<b class="header">defaults</b><code>model.defaults or model.defaults()</code>
<br />
The <b>defaults</b> hash (or function) can be used to specify the default
attributes for your model. When creating an instance of the model,
any unspecified attributes will be set to their default value.
</p>
<pre class="runnable">
var Meal = Backbone.Model.extend({
defaults: {
"appetizer": "caesar salad",
"entree": "ravioli",
"dessert": "cheesecake"
}
});
alert("Dessert will be " + (new Meal).get('dessert'));
</pre>
<p class="warning">
Remember that in JavaScript, objects are passed by reference, so if you
include an object as a default value, it will be shared among all instances.
Instead, define <b>defaults</b> as a function.
</p>
<p id="Model-toJSON">
<b class="header">toJSON</b><code>model.toJSON()</code>
<br />
Return a copy of the model's <a href="#Model-attributes">attributes</a> for JSON stringification.
This can be used for persistence, serialization, or for augmentation before
being handed off to a view. The name of this method is a bit confusing, as
it doesn't actually return a JSON string &mdash; but I'm afraid that it's
the way that the <a href="https://developer.mozilla.org/en/JSON#toJSON()_method">JavaScript API for <b>JSON.stringify</b> works</a>.
</p>
<pre class="runnable">
var artist = new Backbone.Model({
firstName: "Wassily",
lastName: "Kandinsky"
});
artist.set({birthday: "December 16, 1866"});
alert(JSON.stringify(artist));
</pre>
<p id="Model-sync">
<b class="header">sync</b><code>model.sync(method, model, [options])</code>
<br />
Uses <a href="#Sync">Backbone.sync</a> to persist the state of a model to
the server. Can be overridden for custom behavior.
</p>
<p id="Model-fetch">
<b class="header">fetch</b><code>model.fetch([options])</code>
<br />
Resets the model's state from the server by delegating to
<a href="#Sync">Backbone.sync</a>. Returns a
<a href="http://api.jquery.com/jQuery.ajax/#jqXHR">jqXHR</a>.
Useful if the model has never
been populated with data, or if you'd like to ensure that you have the
latest server state. A <tt>"change"</tt> event will be triggered if the
server's state differs from the current attributes. Accepts
<tt>success</tt> and <tt>error</tt> callbacks in the options hash, which
are passed <tt>(model, response, options)</tt>
and <tt>(model, xhr, options)</tt> as arguments, respectively.
</p>
<pre>
// Poll every 10 seconds to keep the channel model up-to-date.
setInterval(function() {
channel.fetch();
}, 10000);
</pre>
<p id="Model-save">
<b class="header">save</b><code>model.save([attributes], [options])</code>
<br />
Save a model to your database (or alternative persistence layer),
by delegating to <a href="#Sync">Backbone.sync</a>. Returns a
<a href="http://api.jquery.com/jQuery.ajax/#jqXHR">jqXHR</a> if
validation is successful and <tt>false</tt> otherwise. The <b>attributes</b>
hash (as in <a href="#Model-set">set</a>) should contain the attributes
you'd like to change &mdash; keys that aren't mentioned won't be altered &mdash; but,
a <i>complete representation</i> of the resource will be sent to the server.
As with <tt>set</tt>, you may pass individual keys and values instead of a hash.
If the model has a <a href="#Model-validate">validate</a>
method, and validation fails, the model will not be saved. If the model
<a href="#Model-isNew">isNew</a>, the save will be a <tt>"create"</tt>
(HTTP <tt>POST</tt>), if the model already
exists on the server, the save will be an <tt>"update"</tt> (HTTP <tt>PUT</tt>).
</p>
<p>
If instead, you'd only like the <i>changed</i> attributes to be sent to the
server, call <tt>model.save(attrs, {patch: true})</tt>. You'll get an HTTP
<tt>PATCH</tt> request to the server with just the passed-in attributes.
</p>
<p>
Calling <tt>save</tt> with new attributes will cause a <tt>"change"</tt>
event immediately, a <tt>"request"</tt> event as the Ajax request begins to
got to the server, and a <tt>"sync"</tt> event after the server has acknowledged
the successful change. Pass <tt>{wait: true}</tt> if you'd like to wait
for the server before setting the new attributes on the model.
</p>
<p>
In the following example, notice how our overridden version
of <tt>Backbone.sync</tt> receives a <tt>"create"</tt> request
the first time the model is saved and an <tt>"update"</tt>
request the second time.
</p>
<pre class="runnable">
Backbone.sync = function(method, model) {
alert(method + ": " + JSON.stringify(model));
model.id = 1;
};
var book = new Backbone.Model({
title: "The Rough Riders",
author: "Theodore Roosevelt"
});
book.save();
book.save({author: "Teddy"});
</pre>
<p>
<b>save</b> accepts <tt>success</tt> and <tt>error</tt> callbacks in the
options hash, which are passed <tt>(model, response, options)</tt> and
<tt>(model, xhr, options)</tt> as arguments, respectively.
The <tt>error</tt> callback will also be invoked if the model has a
<tt>validate</tt> method, and validation fails. If a server-side
validation fails, return a non-<tt>200</tt> HTTP response code, along with
an error response in text or JSON.
</p>
<pre>
book.save("author", "F.D.R.", {error: function(){ ... }});
</pre>
<p id="Model-destroy">
<b class="header">destroy</b><code>model.destroy([options])</code>
<br />
Destroys the model on the server by delegating an HTTP <tt>DELETE</tt>
request to <a href="#Sync">Backbone.sync</a>. Returns a
<a href="http://api.jquery.com/jQuery.ajax/#jqXHR">jqXHR</a> object, or
<tt>false</tt> if the model <a href="#Model-isNew">isNew</a>. Accepts
<tt>success</tt> and <tt>error</tt> callbacks in the options hash, which
are passed <tt>(model, response, options)</tt> and <tt>(model, xhr, options)</tt>
as arguments, respectively.
Triggers a <tt>"destroy"</tt> event on the model, which will bubble up
through any collections that contain it, a <tt>"request"</tt> event as it
begins the Ajax request to the server, and a <tt>"sync"</tt> event, after
the server has successfully acknowledged the model's deletion. Pass
<tt>{wait: true}</tt> if you'd like to wait for the server to respond
before removing the model from the collection.
</p>
<pre>
book.destroy({success: function(model, response) {
...
}});
</pre>
<p id="Model-validate">
<b class="header">validate</b><code>model.validate(attributes)</code>
<br />
This method is left undefined, and you're encouraged to override it with
your custom validation logic, if you have any that can be performed
in JavaScript. <b>validate</b> is called before <tt>set</tt> and
<tt>save</tt>, and is passed the model attributes updated with the values
from <tt>set</tt> or <tt>save</tt>.
If the attributes are valid, don't return anything from <b>validate</b>;
if they are invalid, return an error of your choosing. It
can be as simple as a string error message to be displayed, or a complete
error object that describes the error programmatically. If <b>validate</b>
returns an error, <tt>set</tt> and <tt>save</tt> will not continue, and the
model attributes will not be modified.
Failed validations trigger an <tt>"error"</tt> event.
</p>
<pre class="runnable">
var Chapter = Backbone.Model.extend({
validate: function(attrs) {
if (attrs.end < attrs.start) {
return "can't end before it starts";
}
}
});
var one = new Chapter({
title : "Chapter One: The Beginning"
});
one.on("error", function(model, error) {
alert(model.get("title") + " " + error);
});
one.set({
start: 15,
end: 10
});
</pre>
<p>
<tt>"error"</tt> events are useful for providing coarse-grained error
messages at the model or collection level, but if you have a specific view
that can better handle the error, you may override and suppress the event
by passing an <tt>error</tt> callback directly:
</p>
<pre>
account.set({access: "unlimited"}, {
error: function(model, error) {
alert(error);
}
});
</pre>
<p id="Model-url">
<b class="header">url</b><code>model.url()</code>
<br />
Returns the relative URL where the model's resource would be located on
the server. If your models are located somewhere else, override this method
with the correct logic. Generates URLs of the form: <tt>"/[collection.url]/[id]"</tt>
by default, but you may override by specifying an explicit <tt>urlRoot</tt>
if the model's collection shouldn't be taken into account.
</p>
<p>
Delegates to <a href="#Collection-url">Collection#url</a> to generate the
URL, so make sure that you have it defined, or a <a href="#Model-urlRoot">urlRoot</a>
property, if all models of this class share a common root URL.
A model with an id of <tt>101</tt>, stored in a
<a href="#Collection">Backbone.Collection</a> with a <tt>url</tt> of <tt>"/documents/7/notes"</tt>,
would have this URL: <tt>"/documents/7/notes/101"</tt>
</p>
<p id="Model-urlRoot">
<b class="header">urlRoot</b><code>model.urlRoot or model.urlRoot()</code>
<br />
Specify a <tt>urlRoot</tt> if you're using a model <i>outside</i> of a collection,
to enable the default <a href="#Model-url">url</a> function to generate
URLs based on the model id. <tt>"/[urlRoot]/id"</tt><br />
Normally, you won't need to define this.
Note that <tt>urlRoot</tt> may also be a function.
</p>
<pre class="runnable">
var Book = Backbone.Model.extend({urlRoot : '/books'});
var solaris = new Book({id: "1083-lem-solaris"});
alert(solaris.url());
</pre>
<p id="Model-parse">
<b class="header">parse</b><code>model.parse(response)</code>
<br />
<b>parse</b> is called whenever a model's data is returned by the
server, in <a href="#Model-fetch">fetch</a>, and <a href="#Model-save">save</a>.
The function is passed the raw <tt>response</tt> object, and should return
the attributes hash to be <a href="#Model-set">set</a> on the model. The
default implementation is a no-op, simply passing through the JSON response.
Override this if you need to work with a preexisting API, or better namespace
your responses.
</p>
<p>
If you're working with a Rails backend that has a version prior to 3.1,
you'll notice that its default <tt>to_json</tt> implementation includes
a model's attributes under a namespace. To disable this behavior for
seamless Backbone integration, set:
</p>
<pre>
ActiveRecord::Base.include_root_in_json = false
</pre>
<p id="Model-clone">
<b class="header">clone</b><code>model.clone()</code>
<br />
Returns a new instance of the model with identical attributes.
</p>
<p id="Model-isNew">
<b class="header">isNew</b><code>model.isNew()</code>
<br />
Has this model been saved to the server yet? If the model does not yet have
an <tt>id</tt>, it is considered to be new.
</p>
<p id="Model-change">
<b class="header">change</b><code>model.change()</code>
<br />
Manually trigger the <tt>"change"</tt> event and a <tt>"change:attribute"</tt>
event for each attribute that has changed. If you've been passing
<tt>{silent: true}</tt> to the <a href="#Model-set">set</a> function in order to
aggregate rapid changes to a model, you'll want to call <tt>model.change()</tt>
when you're all finished.
</p>
<p id="Model-hasChanged">
<b class="header">hasChanged</b><code>model.hasChanged([attribute])</code>
<br />
Has the model changed since the last <tt>"change"</tt> event? If an <b>attribute</b>
is passed, returns <tt>true</tt> if that specific attribute has changed.
</p>
<p class="warning">
Note that this method, and the following change-related ones,
are only useful during the course of a <tt>"change"</tt> event.
</p>
<pre>
book.on("change", function() {
if (book.hasChanged("title")) {
...
}
});
</pre>
<p id="Model-changedAttributes">
<b class="header">changedAttributes</b><code>model.changedAttributes([attributes])</code>
<br />
Retrieve a hash of only the model's attributes that have changed. Optionally,
an external <b>attributes</b> hash can be passed in, returning
the attributes in that hash which differ from the model. This can be used
to figure out which portions of a view should be updated, or what calls
need to be made to sync the changes to the server.
</p>
<p id="Model-previous">
<b class="header">previous</b><code>model.previous(attribute)</code>
<br />
During a <tt>"change"</tt> event, this method can be used to get the
previous value of a changed attribute.
</p>
<pre class="runnable">
var bill = new Backbone.Model({
name: "Bill Smith"
});
bill.on("change:name", function(model, name) {
alert("Changed name from " + bill.previous("name") + " to " + name);
});
bill.set({name : "Bill Jones"});
</pre>
<p id="Model-previousAttributes">
<b class="header">previousAttributes</b><code>model.previousAttributes()</code>
<br />
Return a copy of the model's previous attributes. Useful for getting a
diff between versions of a model, or getting back to a valid state after
an error occurs.
</p>
<h2 id="Collection">Backbone.Collection</h2>
<p>
Collections are ordered sets of models. You can bind <tt>"change"</tt> events
to be notified when any model in the collection has been modified,
listen for <tt>"add"</tt> and <tt>"remove"</tt> events, <tt>fetch</tt>
the collection from the server, and use a full suite of
<a href="#Collection-Underscore-Methods">Underscore.js methods</a>.
</p>
<p>
Any event that is triggered on a model in a collection will also be
triggered on the collection directly, for convenience.
This allows you to listen for changes to specific attributes in any
model in a collection, for example:
<tt>Documents.on("change:selected", ...)</tt>
</p>
<p id="Collection-extend">
<b class="header">extend</b><code>Backbone.Collection.extend(properties, [classProperties])</code>
<br />
To create a <b>Collection</b> class of your own, extend <b>Backbone.Collection</b>,
providing instance <b>properties</b>, as well as optional <b>classProperties</b> to be attached
directly to the collection's constructor function.
</p>
<p id="Collection-model">
<b class="header">model</b><code>collection.model</code>
<br />
Override this property to specify the model class that the collection
contains. If defined, you can pass raw attributes objects (and arrays) to
<a href="#Collection-add">add</a>, <a href="#Collection-create">create</a>,
and <a href="#Collection-reset">reset</a>, and the attributes will be
converted into a model of the proper type.
</p>
<pre>
var Library = Backbone.Collection.extend({
model: Book
});
</pre>
<p id="Collection-constructor">
<b class="header">constructor / initialize</b><code>new Collection([models], [options])</code>
<br />
When creating a Collection, you may choose to pass in the initial array
of <b>models</b>. The collection's <a href="#Collection-comparator">comparator</a>
may be included as an option. Passing <tt>false</tt> as the
comparator option will prevent sorting. If you define an
<b>initialize</b> function, it will be invoked when the collection is
created.
</p>
<pre>
var tabs = new TabSet([tab1, tab2, tab3]);
</pre>
<p id="Collection-models">
<b class="header">models</b><code>collection.models</code>
<br />
Raw access to the JavaScript array of models inside of the collection. Usually you'll
want to use <tt>get</tt>, <tt>at</tt>, or the <b>Underscore methods</b>
to access model objects, but occasionally a direct reference to the array
is desired.
</p>
<p id="Collection-toJSON">
<b class="header">toJSON</b><code>collection.toJSON()</code>
<br />
Return an array containing the attributes hash of each model in the
collection. This can be used to serialize and persist the
collection as a whole. The name of this method is a bit confusing, because
it conforms to
<a href="https://developer.mozilla.org/en/JSON#toJSON()_method">JavaScript's JSON API</a>.
</p>
<pre class="runnable">
var collection = new Backbone.Collection([
{name: "Tim", age: 5},
{name: "Ida", age: 26},
{name: "Rob", age: 55}
]);
alert(JSON.stringify(collection));
</pre>
<p id="Collection-sync">
<b class="header">sync</b><code>collection.sync(method, collection, [options])</code>
<br />
Uses <a href="#Sync">Backbone.sync</a> to persist the state of a
collection to the server. Can be overridden for custom behavior.
</p>
<p id="Collection-Underscore-Methods">
<b class="header">Underscore Methods (28)</b>
<br />
Backbone proxies to <b>Underscore.js</b> to provide 28 iteration functions
on <b>Backbone.Collection</b>. They aren't all documented here, but
you can take a look at the Underscore documentation for the full details&hellip;
</p>
<ul class="small">
<li><a href="http://underscorejs.org/#each">forEach (each)</a></li>
<li><a href="http://underscorejs.org/#map">map (collect)</a></li>
<li><a href="http://underscorejs.org/#reduce">reduce (foldl, inject)</a></li>
<li><a href="http://underscorejs.org/#reduceRight">reduceRight (foldr)</a></li>
<li><a href="http://underscorejs.org/#find">find (detect)</a></li>
<li><a href="http://underscorejs.org/#filter">filter (select)</a></li>
<li><a href="http://underscorejs.org/#reject">reject</a></li>
<li><a href="http://underscorejs.org/#all">every (all)</a></li>
<li><a href="http://underscorejs.org/#any">some (any)</a></li>
<li><a href="http://underscorejs.org/#include">include (contains)</a></li>
<li><a href="http://underscorejs.org/#invoke">invoke</a></li>
<li><a href="http://underscorejs.org/#max">max</a></li>
<li><a href="http://underscorejs.org/#min">min</a></li>
<li><a href="http://underscorejs.org/#sortBy">sortBy</a></li>
<li><a href="http://underscorejs.org/#groupBy">groupBy</a></li>
<li><a href="http://underscorejs.org/#sortedIndex">sortedIndex</a></li>
<li><a href="http://underscorejs.org/#shuffle">shuffle</a></li>
<li><a href="http://underscorejs.org/#toArray">toArray</a></li>
<li><a href="http://underscorejs.org/#size">size</a></li>
<li><a href="http://underscorejs.org/#first">first (head, take)</a></li>
<li><a href="http://underscorejs.org/#initial">initial</a></li>
<li><a href="http://underscorejs.org/#rest">rest (tail)</a></li>
<li><a href="http://underscorejs.org/#last">last</a></li>
<li><a href="http://underscorejs.org/#without">without</a></li>
<li><a href="http://underscorejs.org/#indexOf">indexOf</a></li>
<li><a href="http://underscorejs.org/#lastIndexOf">lastIndexOf</a></li>
<li><a href="http://underscorejs.org/#isEmpty">isEmpty</a></li>
<li><a href="http://underscorejs.org/#chain">chain</a></li>
</ul>
<pre>
Books.each(function(book) {
book.publish();
});
var titles = Books.map(function(book) {
return book.get("title");
});
var publishedBooks = Books.filter(function(book) {
return book.get("published") === true;
});
var alphabetical = Books.sortBy(function(book) {
return book.author.get("name").toLowerCase();
});
</pre>
<p id="Collection-add">
<b class="header">add</b><code>collection.add(models, [options])</code>
<br />
Add a model (or an array of models) to the collection. Fires an <tt>"add"</tt>
event, which you can pass <tt>{silent: true}</tt> to suppress. If a
<a href="#Collection-model">model</a> property is defined, you may also pass
raw attributes objects, and have them be vivified as instances of the model.
Pass <tt>{at: index}</tt> to splice the model into the collection at the
specified <tt>index</tt>. If you're adding models to the collection that are
<i>already</i> in the collection, they'll be ignored, unless you pass
<tt>{merge: true}</tt>, in which case their attributes will be merged
into the corresponding models, firing any appropriate <tt>"change"</tt> events.
</p>
<pre class="runnable">
var ships = new Backbone.Collection;
ships.on("add", function(ship) {
alert("Ahoy " + ship.get("name") + "!");
});
ships.add([
{name: "Flying Dutchman"},
{name: "Black Pearl"}
]);
</pre>
<p class="warning">
Note that adding the same model (a model with the same <tt>id</tt>) to
a collection more than once <br /> is a no-op.
</p>
<p id="Collection-remove">
<b class="header">remove</b><code>collection.remove(models, [options])</code>
<br />
Remove a model (or an array of models) from the collection. Fires a
<tt>"remove"</tt> event, which you can use <tt>silent</tt>
to suppress. If you're a callback listening to the <tt>"remove"</tt> event,
the index at which the model is being removed from the collection is available
as <tt>options.index</tt>.
</p>
<p id="Collection-reset">
<b class="header">reset</b><code>collection.reset([models], [options])</code>
<br />
Adding and removing models one at a time is all well and good, but sometimes
you have so many models to change that you'd rather just update the collection
in bulk. Use <b>reset</b> to replace a collection with a new list
of models (or attribute hashes), triggering a single <tt>"reset"</tt> event
at the end. Pass <tt>{silent: true}</tt> to suppress the <tt>"reset"</tt> event.
For convenience, within a <tt>"reset"</tt> event, the list of any previous
models is available as <tt>options.previousModels</tt>.
</p>
<p>
Here's an example using <b>reset</b> to bootstrap a collection during initial page load,
in a Rails application:
</p>
<pre>
&lt;script&gt;
var Accounts = new Backbone.Collection;
Accounts.reset(&lt;%= @accounts.to_json %&gt;);
&lt;/script&gt;
</pre>
<p>
Calling <tt>collection.reset()</tt> without passing any models as arguments
will empty the entire collection.
</p>
<p id="Collection-update">
<b class="header">update</b><code>collection.update(models, [options])</code>
<br />
The <b>update</b> method tries to peform a "smart" update of the collection
with the passed list of models. If a model in the list isn't yet in the
collection it will be added; if the model is already in the collection
its attributes will be merged; and if the collection contains any models that
<i>aren't</i> present in the list, they'll be removed. All of the appropriate
<tt>"add"</tt>, <tt>"remove"</tt>, and <tt>"change"</tt> events are fired
as this happens. If you'd like to customize the behavior, you can disable
it with options: <tt>{add: false}</tt>, <tt>{remove: false}</tt>, or <tt>{merge: false}</tt>.
</p>
<pre>
var vanHalen = new Collection([eddie, alex, stone, roth]);
vanHalen.update([eddie, alex, stone, hagar]);
// Fires a "remove" event for roth, and an "add" event for "hagar".
// Updates any of stone, alex, and eddie's attributes that may have
// changed over the years.
</pre>
<p id="Collection-get">
<b class="header">get</b><code>collection.get(id)</code>
<br />
Get a model from a collection, specified by an <a href="#Model-id">id</a>,
a <a href="#Model-cid">cid</a>, or by passing in a <b>model</b>.
</p>
<pre>
var book = Library.get(110);
</pre>
<p id="Collection-at">
<b class="header">at</b><code>collection.at(index)</code>
<br />
Get a model from a collection, specified by index. Useful if your collection
is sorted, and if your collection isn't sorted, <b>at</b> will still
retrieve models in insertion order.
</p>
<p id="Collection-push">
<b class="header">push</b><code>collection.push(model, [options])</code>
<br />
Add a model at the end of a collection. Takes the same options as
<a href="#Collection-add">add</a>.
</p>
<p id="Collection-pop">
<b class="header">pop</b><code>collection.pop([options])</code>
<br />
Remove and return the last model from a collection. Takes the same options as
<a href="#Collection-remove">remove</a>.
</p>
<p id="Collection-unshift">
<b class="header">unshift</b><code>collection.unshift(model, [options])</code>
<br />
Add a model at the beginning of a collection. Takes the same options as
<a href="#Collection-add">add</a>.
</p>
<p id="Collection-shift">
<b class="header">shift</b><code>collection.shift([options])</code>
<br />
Remove and return the first model from a collection. Takes the same options as
<a href="#Collection-remove">remove</a>.
</p>
<p id="Collection-length">
<b class="header">length</b><code>collection.length</code>
<br />
Like an array, a Collection maintains a <tt>length</tt> property, counting
the number of models it contains.
</p>
<p id="Collection-comparator">
<b class="header">comparator</b><code>collection.comparator</code>
<br />
By default there is no <b>comparator</b> for a collection.
If you define a comparator, it will be used to maintain
the collection in sorted order. This means that as models are added,
they are inserted at the correct index in <tt>collection.models</tt>.
A comparator can be defined as a
<a href="http://underscorejs.org/#sortBy">sortBy</a>
(pass a function that takes a single argument),
as a
<a href="https://developer.mozilla.org/en/JavaScript/Reference/Global_Objects/Array/sort">sort</a>
(pass a comparator function that expects two arguments),
or as a string indicating the attribute to sort by.
</p>
<p>
"sortBy" comparator functions take a model and return a numeric or string
value by which the model should be ordered relative to others.
"sort" comparator functions take two models, and return <tt>-1</tt> if
the first model should come before the second, <tt>0</tt> if they are of
the same rank and <tt>1</tt> if the first model should come after.
</p>
<p>
Note how even though all of the chapters in this example are added backwards,
they come out in the proper order:
</p>
<pre class="runnable">
var Chapter = Backbone.Model;
var chapters = new Backbone.Collection;
chapters.comparator = function(chapter) {
return chapter.get("page");
};
chapters.add(new Chapter({page: 9, title: "The End"}));
chapters.add(new Chapter({page: 5, title: "The Middle"}));
chapters.add(new Chapter({page: 1, title: "The Beginning"}));
alert(chapters.pluck('title'));
</pre>
<p class="warning">
Collections with a comparator will not automatically re-sort if you
later change model attributes, so you may wish to call
<tt>sort</tt> after changing model attributes that would affect the order.
</p>
<p id="Collection-sort">
<b class="header">sort</b><code>collection.sort([options])</code>
<br />
Force a collection to re-sort itself. You don't need to call this under
normal circumstances, as a collection with a <a href="#Collection-comparator">comparator</a>
will sort itself whenever a model is added. Calling <b>sort</b>
triggers a <tt>"sort"</tt> event on the collection, unless silenced by passing
<tt>{silent: true}</tt>
</p>
<p id="Collection-pluck">
<b class="header">pluck</b><code>collection.pluck(attribute)</code>
<br />
Pluck an attribute from each model in the collection. Equivalent to calling
<tt>map</tt>, and returning a single attribute from the iterator.
</p>
<pre class="runnable">
var stooges = new Backbone.Collection([
{name: "Curly"},
{name: "Larry"},
{name: "Moe"}
]);
var names = stooges.pluck("name");
alert(JSON.stringify(names));
</pre>
<p id="Collection-where">
<b class="header">where</b><code>collection.where(attributes)</code>
<br />
Return an array of all the models in a collection that match the
passed <b>attributes</b>. Useful for simple cases of <tt>filter</tt>.
</p>
<pre class="runnable">
var friends = new Backbone.Collection([
{name: "Athos", job: "Musketeer"},
{name: "Porthos", job: "Musketeer"},
{name: "Aramis", job: "Musketeer"},
{name: "d'Artagnan", job: "Guard"},
]);
var musketeers = friends.where({job: "Musketeer"});
alert(musketeers.length);
</pre>
<p id="Collection-url">
<b class="header">url</b><code>collection.url or collection.url()</code>
<br />
Set the <b>url</b> property (or function) on a collection to reference
its location on the server. Models within the collection will use <b>url</b>
to construct URLs of their own.
</p>
<pre>
var Notes = Backbone.Collection.extend({
url: '/notes'
});
// Or, something more sophisticated:
var Notes = Backbone.Collection.extend({
url: function() {
return this.document.url() + '/notes';
}
});
</pre>
<p id="Collection-parse">
<b class="header">parse</b><code>collection.parse(response)</code>
<br />
<b>parse</b> is called by Backbone whenever a collection's models are
returned by the server, in <a href="#Collection-fetch">fetch</a>.
The function is passed the raw <tt>response</tt> object, and should return
the array of model attributes to be <a href="#Collection-add">added</a>
to the collection. The default implementation is a no-op, simply passing
through the JSON response. Override this if you need to work with a
preexisting API, or better namespace your responses.
</p>
<pre>
var Tweets = Backbone.Collection.extend({
// The Twitter Search API returns tweets under "results".
parse: function(response) {
return response.results;
}
});
</pre>
<p id="Collection-clone">
<b class="header">clone</b><code>collection.clone()</code>
<br />
Returns a new instance of the collection with an identical list of models.
</p>
<p id="Collection-fetch">
<b class="header">fetch</b><code>collection.fetch([options])</code>
<br />
Fetch the default set of models for this collection from the server,
resetting the collection when they arrive. The <b>options</b> hash takes
<tt>success</tt> and <tt>error</tt>
callbacks which will be passed <tt>(collection, response, options)</tt>
and <tt>(collection, xhr, options)</tt> as arguments, respectively.
When the model data returns from the server, the collection will be (efficiently)
<a href="#Collection-reset">reset</a>, unless you pass <tt>{update: true}</tt>,
in which case it will use <a href="#Collection-update">update</a> to (intelligently)
merge the fetched models.
Delegates to <a href="#Sync">Backbone.sync</a>
under the covers for custom persistence strategies and returns a
<a href="http://api.jquery.com/jQuery.ajax/#jqXHR">jqXHR</a>.
The server handler for <b>fetch</b> requests should return a JSON array of
models.
</p>
<pre class="runnable">
Backbone.sync = function(method, model) {
alert(method + ": " + model.url);
};
var Accounts = new Backbone.Collection;
Accounts.url = '/accounts';
Accounts.fetch();
</pre>
<p>
The behavior of <b>fetch</b> can be customized by using the available
<a href="#Collection-update">update</a> options. For example, to fetch a
collection, getting an <tt>"add"</tt> event for every new model, and
a <tt>"change"</tt> event for every changed existing model, without
removing anything: <tt>collection.fetch({update: true, remove: false})</tt>
</p>
<p>
<b>jQuery.ajax</b> options can also be passed directly as <b>fetch</b> options,
so to fetch a specific page of a paginated collection:
<tt>Documents.fetch({data: {page: 3}})</tt>
</p>
<p>
Note that <b>fetch</b> should not be used to populate collections on
page load &mdash; all models needed at load time should already be
<a href="#FAQ-bootstrap">bootstrapped</a> in to place. <b>fetch</b> is
intended for lazily-loading models for interfaces that are not needed
immediately: for example, documents with collections of notes that may be
toggled open and closed.
</p>
<p id="Collection-create">
<b class="header">create</b><code>collection.create(attributes, [options])</code>
<br />
Convenience to create a new instance of a model within a collection.
Equivalent to instantiating a model with a hash of attributes,
saving the model to the server, and adding the model to the set after being
successfully created. Returns
the model, or <tt>false</tt> if a validation error prevented the
model from being created. In order for this to work, you should set the
<a href="#Collection-model">model</a> property of the collection.
The <b>create</b> method can accept either an attributes hash or an
existing, unsaved model object.
</p>
<p>
Creating a model will cause an immediate <tt>"add"</tt> event to be
triggered on the collection, a <tt>"request"</tt> event as the new model is
sent to the server, as well as a <tt>"sync"</tt> event, once the
server has responded with the successful creation of the model. Pass <tt>{wait: true}</tt>
if you'd like to wait for the server before adding the new model to the collection.
</p>
<pre>
var Library = Backbone.Collection.extend({
model: Book
});
var NYPL = new Library;
var othello = NYPL.create({
title: "Othello",
author: "William Shakespeare"
});
</pre>
<h2 id="Router">Backbone.Router</h2>
<p>
Web applications often provide linkable, bookmarkable, shareable URLs for
important locations in the app. Until recently, hash fragments
(<tt>#page</tt>) were used to provide these permalinks, but with the
arrival of the History API, it's now possible to use standard URLs (<tt>/page</tt>).
<b>Backbone.Router</b> provides methods for routing client-side pages, and
connecting them to actions and events. For browsers which don't yet support
the History API, the Router handles graceful fallback and transparent
translation to the fragment version of the URL.
</p>
<p>
During page load, after your application has finished creating all of its routers,
be sure to call <tt>Backbone.history.start()</tt>, or
<tt>Backbone.history.start({pushState: true})</tt> to route the initial URL.
</p>
<p id="Router-extend">
<b class="header">extend</b><code>Backbone.Router.extend(properties, [classProperties])</code>
<br />
Get started by creating a custom router class. Define actions that are
triggered when certain URL fragments are
matched, and provide a <a href="#Router-routes">routes</a> hash
that pairs routes to actions. Note that you'll want to avoid using a
leading slash in your route definitions:
</p>
<pre>
var Workspace = Backbone.Router.extend({
routes: {
"help": "help", // #help
"search/:query": "search", // #search/kiwis
"search/:query/p:page": "search" // #search/kiwis/p7
},
help: function() {
...
},
search: function(query, page) {
...
}
});
</pre>
<p id="Router-routes">
<b class="header">routes</b><code>router.routes</code>
<br />
The routes hash maps URLs with parameters to functions on your router,
similar to the <a href="#View">View</a>'s <a href="#View-delegateEvents">events hash</a>.
Routes can contain parameter parts, <tt>:param</tt>, which match a single URL
component between slashes; and splat parts <tt>*splat</tt>, which can match
any number of URL components. Part of a route can be made optional by
surrounding it in parentheses <tt>(/:optional)</tt>.
</p>
<p>
For example, a route of <tt>"search/:query/p:page"</tt> will match
a fragment of <tt>#search/obama/p2</tt>, passing <tt>"obama"</tt>
and <tt>"2"</tt> to the action.
</p>
<p>
A route of <tt>"file/*path"</tt> will match
<tt>#file/nested/folder/file.txt</tt>, passing
<tt>"nested/folder/file.txt"</tt> to the action.
</p>
<p>
A route of <tt>"docs/:section(/:subsection)"</tt> will match
<tt>#docs/faq</tt> and <tt>#docs/faq/installing</tt>, passing
<tt>"faq"</tt> to the action in the first case, and passing <tt>"faq"</tt>
and <tt>"installing"</tt> to the action in the second.
</p>
<p>
When the visitor presses the back button, or enters a URL, and a particular
route is matched, the name of the action will be fired as an
<a href="#Events">event</a>, so that other objects can listen to the router,
and be notified. In the following example, visiting <tt>#help/uploading</tt>
will fire a <tt>route:help</tt> event from the router.
</p>
<pre>
routes: {
"help/:page": "help",
"download/*path": "download",
"folder/:name": "openFolder",
"folder/:name-:mode": "openFolder"
}
</pre>
<pre>
router.on("route:help", function(page) {
...
});
</pre>
<p id="Router-constructor">
<b class="header">constructor / initialize</b><code>new Router([options])</code>
<br />
When creating a new router, you may pass its
<a href="#Router-routes">routes</a> hash directly as an option, if you
choose. All <tt>options</tt> will also be passed to your <tt>initialize</tt>
function, if defined.
</p>
<p id="Router-route">
<b class="header">route</b><code>router.route(route, name, [callback])</code>
<br />
Manually create a route for the router, The <tt>route</tt> argument may
be a <a href="#Router-routes">routing string</a> or regular expression.
Each matching capture from the route or regular expression will be passed as
an argument to the callback. The <tt>name</tt> argument will be triggered as
a <tt>"route:name"</tt> event whenever the route is matched. If the
<tt>callback</tt> argument is omitted <tt>router[name]</tt> will be used
instead.
</p>
<pre>
initialize: function(options) {
// Matches #page/10, passing "10"
this.route("page/:number", "page", function(number){ ... });
// Matches /117-a/b/c/open, passing "117-a/b/c" to this.open
this.route(/^(.*?)\/open$/, "open");
},
open: function(id) { ... }
</pre>
<p id="Router-navigate">
<b class="header">navigate</b><code>router.navigate(fragment, [options])</code>
<br />
Whenever you reach a point in your application that you'd like to save
as a URL, call <b>navigate</b> in order to update the URL.
If you wish to also call the route function, set the <b>trigger</b>
option to <tt>true</tt>.
To update the URL without creating an entry in the browser's history,
set the <b>replace</b> option to <tt>true</tt>.
</p>
<pre>
openPage: function(pageNumber) {
this.document.pages.at(pageNumber).open();
this.navigate("page/" + pageNumber);
}
# Or ...
app.navigate("help/troubleshooting", {trigger: true});
# Or ...
app.navigate("help/troubleshooting", {trigger: true, replace: true});
</pre>
<h2 id="History">Backbone.history</h2>
<p>
<b>History</b> serves as a global router (per frame) to handle <tt>hashchange</tt>
events or <tt>pushState</tt>, match the appropriate route, and trigger callbacks. You shouldn't
ever have to create one of these yourself &mdash; you should use the reference
to <tt>Backbone.history</tt> that will be created for you automatically if you make use
of <a href="#Router">Routers</a> with <a href="#Router-routes">routes</a>.
</p>
<p>
<b>pushState</b> support exists on a purely opt-in basis in Backbone.
Older browsers that don't support <tt>pushState</tt> will continue to use
hash-based URL fragments, and if a hash URL is visited by a
<tt>pushState</tt>-capable browser, it will be transparently upgraded to
the true URL. Note that using real URLs requires your web server to be
able to correctly render those pages, so back-end changes are required
as well. For example, if you have a route of <tt>/documents/100</tt>,
your web server must be able to serve that page, if the browser
visits that URL directly. For full search-engine crawlability, it's best to
have the server generate the complete HTML for the page ... but if it's a web
application, just rendering the same content you would have for the root URL,
and filling in the rest with Backbone Views and JavaScript works fine.
</p>
<p id="History-start">
<b class="header">start</b><code>Backbone.history.start([options])</code>
<br />
When all of your <a href="#Router">Routers</a> have been created,
and all of the routes are set up properly, call <tt>Backbone.history.start()</tt>
to begin monitoring <tt>hashchange</tt> events, and dispatching routes.
</p>
<p>
To indicate that you'd like to use HTML5 <tt>pushState</tt> support in
your application, use <tt>Backbone.history.start({pushState: true})</tt>.
If you'd like to use <tt>pushState</tt>, but have browsers that don't support
it natively use full page refreshes instead, you can add
<tt>{hashChange: false}</tt> to the options.
</p>
<p>
If your application is not being served from the root url <tt>/</tt> of your
domain, be sure to tell History where the root really is, as an option:
<tt>Backbone.history.start({pushState: true, root: "/public/search/"})</tt>
</p>
<p>
When called, if a route succeeds with a match for the current URL,
<tt>Backbone.history.start()</tt> returns <tt>true</tt>. If no defined
route matches the current URL, it returns <tt>false</tt>.
</p>
<p>
If the server has already rendered the entire page, and you don't want the
initial route to trigger when starting History, pass <tt>silent: true</tt>.
</p>
<p>
Because hash-based history in Internet Explorer relies on an
<tt>&lt;iframe&gt;</tt>, be sure to only call <tt>start()</tt> after the DOM
is ready.
</p>
<pre>
$(function(){
new WorkspaceRouter();
new HelpPaneRouter();
Backbone.history.start({pushState: true});
});
</pre>
<h2 id="Sync">Backbone.sync</h2>
<p>
<b>Backbone.sync</b> is the function that Backbone calls every time it
attempts to read or save a model to the server. By default, it uses
<tt>(jQuery/Zepto).ajax</tt> to make a RESTful JSON request and returns a
<a href="http://api.jquery.com/jQuery.ajax/#jqXHR">jqXHR</a>. You can override
it in order to use a different persistence strategy, such as WebSockets,
XML transport, or Local Storage.
</p>
<p>
The method signature of <b>Backbone.sync</b> is <tt>sync(method, model, [options])</tt>
</p>
<ul>
<li><b>method</b> – the CRUD method (<tt>"create"</tt>, <tt>"read"</tt>, <tt>"update"</tt>, or <tt>"delete"</tt>)</li>
<li><b>model</b> – the model to be saved (or collection to be read)</li>
<li><b>options</b> – success and error callbacks, and all other jQuery request options</li>
</ul>
<p>
With the default implementation, when <b>Backbone.sync</b> sends up a request to save
a model, its attributes will be passed, serialized as JSON, and sent in the HTTP body
with content-type <tt>application/json</tt>. When returning a JSON response,
send down the attributes of the model that have been changed by the server, and need
to be updated on the client. When responding to a <tt>"read"</tt> request from a collection
(<a href="#Collection#fetch">Collection#fetch</a>), send down an array
of model attribute objects.
</p>
<p>
Whenever a model or collection begins a <b>sync</b> with the server, a
<tt>"request"</tt> event is emitted. If the request completes successfully
you'll get a <tt>"sync"</tt> event, and an <tt>"error"</tt> event if not.
</p>
<p>
The <b>sync</b> function may be overriden globally as <tt>Backbone.sync</tt>,
or at a finer-grained level, by adding a <tt>sync</tt> function to a Backbone
collection or to an individual model.
</p>
<p>
The default <b>sync</b> handler maps CRUD to REST like so:
</p>
<ul>
<li><b>create &rarr; POST &nbsp; </b><tt>/collection</tt></li>
<li><b>read &rarr; GET &nbsp; </b><tt>/collection[/id]</tt></li>
<li><b>update &rarr; PUT &nbsp; </b><tt>/collection/id</tt></li>
<li><b>delete &rarr; DELETE &nbsp; </b><tt>/collection/id</tt></li>
</ul>
<p>
As an example, a Rails handler responding to an <tt>"update"</tt> call from
<tt>Backbone</tt> might look like this: <i>(In real code, never use
</i><tt>update_attributes</tt><i> blindly, and always whitelist the attributes
you allow to be changed.)</i>
</p>
<pre>
def update
account = Account.find params[:id]
account.update_attributes params
render :json => account
end
</pre>
<p>
One more tip for integrating Rails versions prior to 3.1 is to disable
the default namespacing for <tt>to_json</tt> calls on models by setting
<tt>ActiveRecord::Base.include_root_in_json = false</tt>
</p>
<p id="Sync-ajax">
<b class="header">ajax</b><code>Backbone.ajax = function(request) { ... };</code>
<br />
If you want to use a custom AJAX function, or your endpoint doesn't support
the <a href="http://api.jquery.com/jQuery.ajax/">jQuery.ajax</a> API
and you need to tweak things, you can do so by setting <tt>Backbone.ajax</tt>.
</p>
<p id="Sync-emulateHTTP">
<b class="header">emulateHTTP</b><code>Backbone.emulateHTTP = true</code>
<br />
If you want to work with a legacy web server that doesn't support Backbone's
default REST/HTTP approach, you may choose to turn on <tt>Backbone.emulateHTTP</tt>.
Setting this option will fake <tt>PUT</tt> and <tt>DELETE</tt> requests with
a HTTP <tt>POST</tt>, setting the <tt>X-HTTP-Method-Override</tt> header
with the true method. If <tt>emulateJSON</tt> is also on, the true method
will be passed as an additional <tt>_method</tt> parameter.
</p>
<pre>
Backbone.emulateHTTP = true;
model.save(); // POST to "/collection/id", with "_method=PUT" + header.
</pre>
<p id="Sync-emulateJSON">
<b class="header">emulateJSON</b><code>Backbone.emulateJSON = true</code>
<br />
If you're working with a legacy web server that can't handle requests
encoded as <tt>application/json</tt>, setting <tt>Backbone.emulateJSON = true;</tt>
will cause the JSON to be serialized under a <tt>model</tt> parameter, and
the request to be made with a <tt>application/x-www-form-urlencoded</tt>
mime type, as if from an HTML form.
</p>
<h2 id="View">Backbone.View</h2>
<p>
Backbone views are almost more convention than they are code &mdash; they
don't determine anything about your HTML or CSS for you, and can be used
with any JavaScript templating library.
The general idea is to organize your interface into logical views,
backed by models, each of which can be updated independently when the
model changes, without having to redraw the page. Instead of digging into
a JSON object, looking up an element in the DOM, and updating the HTML by hand,
you can bind your view's <tt>render</tt> function to the model's <tt>"change"</tt>
event &mdash; and now everywhere that
model data is displayed in the UI, it is always immediately up to date.
</p>
<p id="View-extend">
<b class="header">extend</b><code>Backbone.View.extend(properties, [classProperties])</code>
<br />
Get started with views by creating a custom view class. You'll want to
override the <a href="#View-render">render</a> function, specify your
declarative <a href="#View-delegateEvents">events</a>, and perhaps the
<tt>tagName</tt>, <tt>className</tt>, or <tt>id</tt> of the View's root
element.
</p>
<pre>
var DocumentRow = Backbone.View.extend({
tagName: "li",
className: "document-row",
events: {
"click .icon": "open",
"click .button.edit": "openEditDialog",
"click .button.delete": "destroy"
},
initialize: function() {
this.listenTo(this.model, "change", this.render);
}
render: function() {
...
}
});
</pre>
<p>
Properties like <tt>tagName</tt>, <tt>id</tt>, <tt>className</tt>,
<tt>el</tt>, and <tt>events</tt> may also be defined as a function, if
you want to wait to define them until runtime.
</p>
<p id="View-constructor">
<b class="header">constructor / initialize</b><code>new View([options])</code>
<br />
When creating a new View, the options you pass &mdash; after being merged
into any default options already present on the view &mdash;
are attached to the view as <tt>this.options</tt> for future reference.
There are several special
options that, if passed, will be attached directly to the view:
<tt>model</tt>, <tt>collection</tt>,
<tt>el</tt>, <tt>id</tt>, <tt>className</tt>, <tt>tagName</tt> and <tt>attributes</tt>.
If the view defines an <b>initialize</b> function, it will be called when
the view is first created. If you'd like to create a view that references
an element <i>already</i> in the DOM, pass in the element as an option:
<tt>new View({el: existingElement})</tt>
</p>
<pre>
var doc = Documents.first();
new DocumentRow({
model: doc,
id: "document-row-" + doc.id
});
</pre>
<p id="View-el">
<b class="header">el</b><code>view.el</code>
<br />
All views have a DOM element at all times (the <b>el</b> property),
whether they've already been inserted into the page or not. In this
fashion, views can be rendered at any time, and inserted into the DOM all
at once, in order to get high-performance UI rendering with as few
reflows and repaints as possible. <tt>this.el</tt> is created from the
view's <tt>tagName</tt>, <tt>className</tt>, <tt>id</tt> and <tt>attributes</tt> properties,
if specified. If not, <b>el</b> is an empty <tt>div</tt>.
</p>
<pre class="runnable">
var ItemView = Backbone.View.extend({
tagName: 'li'
});
var BodyView = Backbone.View.extend({
el: 'body'
});
var item = new ItemView();
var body = new BodyView();
alert(item.el + ' ' + body.el);
</pre>
<p id="View-$el">
<b class="header">$el</b><code>view.$el</code>
<br />
A cached jQuery (or Zepto) object for the view's element. A handy
reference instead of re-wrapping the DOM element all the time.
</p>
<pre>
view.$el.show();
listView.$el.append(itemView.el);
</pre>
<p id="View-setElement">
<b class="header">setElement</b><code>view.setElement(element)</code>
<br />
If you'd like to apply a Backbone view to a different DOM element, use
<b>setElement</b>, which will also create the cached <tt>$el</tt> reference
and move the view's delegated events from the old element to the new one.
</p>
<p id="View-attributes">
<b class="header">attributes</b><code>view.attributes</code>
<br />
A hash of attributes that will be set as HTML DOM element attributes on the
view's <tt>el</tt> (id, class, data-properties, etc.), or a function that
returns such a hash.
</p>
<p id="View-dollar">
<b class="header">$ (jQuery or Zepto)</b><code>view.$(selector)</code>
<br />
If jQuery or Zepto is included on the page, each view has a
<b>$</b> function that runs queries scoped within the view's element. If you use this
scoped jQuery function, you don't have to use model ids as part of your query
to pull out specific elements in a list, and can rely much more on HTML class
attributes. It's equivalent to running: <tt>view.$el.find(selector)</tt>
</p>
<pre>
ui.Chapter = Backbone.View.extend({
serialize : function() {
return {
title: this.$(".title").text(),
start: this.$(".start-page").text(),
end: this.$(".end-page").text()
};
}
});
</pre>
<p id="View-render">
<b class="header">render</b><code>view.render()</code>
<br />
The default implementation of <b>render</b> is a no-op. Override this
function with your code that renders the view template from model data,
and updates <tt>this.el</tt> with the new HTML. A good
convention is to <tt>return this</tt> at the end of <b>render</b> to
enable chained calls.
</p>
<pre>
var Bookmark = Backbone.View.extend({
template: _.template(…),
render: function() {
this.$el.html(this.template(this.model.toJSON()));
return this;
}
});
</pre>
<p>
Backbone is agnostic with respect to your preferred method of HTML templating.
Your <b>render</b> function could even munge together an HTML string, or use
<tt>document.createElement</tt> to generate a DOM tree. However, we suggest
choosing a nice JavaScript templating library.
<a href="http://github.com/janl/mustache.js">Mustache.js</a>,
<a href="http://github.com/creationix/haml-js">Haml-js</a>, and
<a href="http://github.com/sstephenson/eco">Eco</a> are all fine alternatives.
Because <a href="http://underscorejs.org/">Underscore.js</a> is already on the page,
<a href="http://underscorejs.org/#template">_.template</a>
is available, and is an excellent choice if you prefer simple
interpolated-JavaScript style templates.
</p>
<p>
Whatever templating strategy you end up with, it's nice if you <i>never</i>
have to put strings of HTML in your JavaScript. At DocumentCloud, we
use <a href="http://documentcloud.github.com/jammit/">Jammit</a> in order
to package up JavaScript templates stored in <tt>/app/views</tt> as part
of our main <tt>core.js</tt> asset package.
</p>
<p id="View-remove">
<b class="header">remove</b><code>view.remove()</code>
<br />
Removes a view from the DOM, and calls
<a href="#Events-stopListening">stopListening</a> to remove any bound
model events that the view has <a href="#Events-listenTo">listenTo</a>'d.
</p>
<p id="View-make">
<b class="header">make</b><code>view.make(tagName, [attributes], [content])</code>
<br />
Convenience function for creating a DOM element of the given type (<b>tagName</b>),
with optional attributes and HTML content. Used internally to create the
initial <tt>view.el</tt>.
</p>
<pre class="runnable">
var view = new Backbone.View;
var el = view.make("b", {"class": "bold"}, "Bold! ");
$("#make-demo").append(el);
</pre>
<div id="make-demo"></div>
<p id="View-delegateEvents">
<b class="header">delegateEvents</b><code>delegateEvents([events])</code>
<br />
Uses jQuery's <tt>delegate</tt> function to provide declarative callbacks
for DOM events within a view.
If an <b>events</b> hash is not passed directly, uses <tt>this.events</tt>
as the source. Events are written in the format <tt>{"event selector": "callback"}</tt>.
The callback may be either the name of a method on the view, or a direct
function body.
Omitting the <tt>selector</tt> causes the event to be bound to the view's
root element (<tt>this.el</tt>). By default, <tt>delegateEvents</tt> is called
within the View's constructor for you, so if you have a simple <tt>events</tt>
hash, all of your DOM events will always already be connected, and you will
never have to call this function yourself.
</p>
<p>
The <tt>events</tt> property may also be defined as a function that returns
an <b>events</b> hash, to make it easier to programmatically define your
events, as well as inherit them from parent views.
</p>
<p>
Using <b>delegateEvents</b> provides a number of advantages over manually
using jQuery to bind events to child elements during <a href="#View-render">render</a>. All attached
callbacks are bound to the view before being handed off to jQuery, so when
the callbacks are invoked, <tt>this</tt> continues to refer to the view object. When
<b>delegateEvents</b> is run again, perhaps with a different <tt>events</tt>
hash, all callbacks are removed and delegated afresh &mdash; useful for
views which need to behave differently when in different modes.
</p>
<p>
A view that displays a document in a search result might look
something like this:
</p>
<pre>
var DocumentView = Backbone.View.extend({
events: {
"dblclick" : "open",
"click .icon.doc" : "select",
"contextmenu .icon.doc" : "showMenu",
"click .show_notes" : "toggleNotes",
"click .title .lock" : "editAccessLevel",
"mouseover .title .date" : "showTooltip"
},
render: function() {
this.$el.html(this.template(this.model.toJSON()));
return this;
},
open: function() {
window.open(this.model.get("viewer_url"));
},
select: function() {
this.model.set({selected: true});
},
...
});
</pre>
<p id="View-undelegateEvents">
<b class="header">undelegateEvents</b><code>undelegateEvents()</code>
<br />
Removes all of the view's delegated events. Useful if you want to disable
or remove a view from the DOM temporarily.
</p>
<h2 id="Utility">Utility</h2>
<p id="Utility-Backbone-noConflict">
<b class="header">Backbone.noConflict</b><code>var backbone = Backbone.noConflict();</code>
<br />
Returns the <tt>Backbone</tt> object back to its original value. You can
use the return value of <tt>Backbone.noConflict()</tt> to keep a local
reference to Backbone. Useful for embedding Backbone on third-party
websites, where you don't want to clobber the existing Backbone.
</p>
<pre>
var localBackbone = Backbone.noConflict();
var model = localBackbone.Model.extend(...);
</pre>
<p id="Utility-Backbone-$">
<b class="header">Backbone.$</b><code>Backbone.$ = $;</code>
<br />
If you have multiple copies of <tt>jQuery</tt> on the page, or simply want
to tell Backbone to use a particular object as its DOM / Ajax library,
this is the property for you.
</p>
<h2 id="examples">Examples</h2>
<p>
The list of examples that follows, while long, is not exhaustive. If you've
worked on an app that uses Backbone, please add it to the
<a href="https://github.com/documentcloud/backbone/wiki/Projects-and-Companies-using-Backbone">wiki page of Backbone apps</a>.
</p>
<p id="examples-todos">
<a href="http://jgn.me/">Jérôme Gravel-Niquet</a> has contributed a
<a href="examples/todos/index.html">Todo List application</a>
that is bundled in the repository as Backbone example. If you're wondering
where to get started with Backbone in general, take a moment to
<a href="docs/todos.html">read through the annotated source</a>. The app uses a
<a href="docs/backbone-localstorage.html">LocalStorage adapter</a>
to transparently save all of your todos within your browser, instead of
sending them to a server. Jérôme also has a version hosted at
<a href="http://localtodos.com/">localtodos.com</a> that uses a
<a href="http://github.com/jeromegn/backbone-mootools">MooTools-backed version of Backbone</a>
instead of jQuery.
</p>
<div style="text-align: center;">
<a href="examples/todos/index.html">
<img width="400" height="427" data-original="docs/images/todos.png" alt="Todos" class="example_image" />
</a>
</div>
<h2 id="examples-documentcloud">DocumentCloud</h2>
<p>
The <a href="http://www.documentcloud.org/public/#search/">DocumentCloud workspace</a>
is built on Backbone.js, with <i>Documents</i>, <i>Projects</i>,
<i>Notes</i>, and <i>Accounts</i> all as Backbone models and collections.
If you're interested in history &mdash; both Underscore.js and Backbone.js
were originally extracted from the DocumentCloud codebase, and packaged
into standalone JS libraries.
</p>
<div style="text-align: center;">
<a href="http://www.documentcloud.org/public/#search/">
<img width="550" height="453" data-original="docs/images/dc-workspace.png" alt="DocumentCloud Workspace" class="example_image" />
</a>
</div>
<h2 id="examples-usa-today">USA Today</h2>
<p>
<a href="http://usatoday.com">USA Today</a> takes advantage of the modularity of
Backbone's data/model lifecycle &mdash; which makes it simple to create, inherit,
isolate, and link application objects &mdash; to keep the codebase both manageable and efficient.
The new website also makes heavy use of the Backbone Router to control the
page for both pushState-capable and legacy browsers.
Finally, the team took advantage of Backbone's Event module to create a
PubSub API that allows third parties and analytics packages to hook into the
heart of the app.
</p>
<div style="text-align: center;">
<a href="http://usatoday.com">
<img width="550" height="532" data-original="docs/images/usa-today.png" alt="USA Today" class="example_image" />
</a>
</div>
<h2 id="examples-rdio">Rdio</h2>
<p>
<a href="http://rdio.com/new">New Rdio</a> was developed from the ground
up with a component based framework based on Backbone.js. Every component
on the screen is dynamically loaded and rendered, with data provided by the
<a href="http://developer.rdio.com/">Rdio API</a>. When changes are pushed,
every component can update itself without reloading the page or interrupting
the user's music. All of this relies on Backbone's views and models,
and all URL routing is handled by Backbone's Router. When data changes are
signaled in realtime, Backbone's Events notify the interested components
in the data changes. Backbone forms the core of the new, dynamic, realtime
Rdio web and <i>desktop</i> applications.
</p>
<div style="text-align: center;">
<a href="http://rdio.com/new">
<img width="550" height="344" data-original="docs/images/rdio.png" alt="Rdio" class="example_image" />
</a>
</div>
<h2 id="examples-linkedin">LinkedIn Mobile</h2>
<p>
<a href="http://www.linkedin.com/">LinkedIn</a> used Backbone.js to create
its <a href="http://www.linkedin.com/static?key=mobile">next-generation HTML5 mobile web app</a>.
Backbone made it easy to keep the app modular, organized and extensible so
that it was possible to program the complexities of LinkedIn's user experience.
The app also uses <a href="http://zeptojs.com/">Zepto</a>,
<a href="http://underscorejs.org/">Underscore.js</a>,
<a href="http://sass-lang.com/">SASS</a>, <a href="http://cubiq.org/iscroll">iScroll</a>,
HTML5 LocalStorage and Canvas. The tech team blogged about
<a href="http://engineering.linkedin.com/mobile/linkedin-ipad-using-local-storage-snappy-mobile-apps">their experiences using LocalStorage</a>
to improve mobile performance.
</p>
<div style="text-align: center;">
<a href="http://www.linkedin.com/static?key=mobile">
<img width="550" height"454" data-original="docs/images/linkedin-mobile.png" alt="LinkedIn Mobile" class="example_image" />
</a>
</div>
<h2 id="examples-hulu">Hulu</h2>
<p>
<a href="http://hulu.com">Hulu</a> used Backbone.js to build its next
generation online video experience. With Backbone as a foundation, the
web interface was rewritten from scratch so that all page content can
be loaded dynamically with smooth transitions as you navigate.
Backbone makes it easy to move through the app quickly without the
reloading of scripts and embedded videos, while also offering models and
collections for additional data manipulation support.
</p>
<div style="text-align: center;">
<a href="http://hulu.com">
<img width="550" height="449" data-original="docs/images/hulu.png" alt="Hulu" class="example_image" />
</a>
</div>
<h2 id="examples-flow">Flow</h2>
<p>
<a href="http://www.metalabdesign.com/">MetaLab</a> used Backbone.js to create
<a href="http://www.getflow.com/">Flow</a>, a task management app for teams. The
workspace relies on Backbone.js to construct task views, activities, accounts,
folders, projects, and tags. You can see the internals under <tt>window.Flow</tt>.
</p>
<div style="text-align: center;">
<a href="http://www.getflow.com/">
<img width="550" height="416" data-original="docs/images/flow.png" alt="Flow" class="example_image" />
</a>
</div>
<h2 id="examples-gilt">Gilt Groupe</h2>
<p>
<a href="http://gilt.com">Gilt Groupe</a> uses Backbone.js to build multiple
applications across their family of sites.
<a href="http://m.gilt.com">Gilt's mobile website</a> uses Backbone and
<a href="http://zeptojs.com">Zepto.js</a> to create a blazing-fast
shopping experience for users on-the-go, while
<a href="http://live.gilt.com">Gilt Live</a> combines Backbone with
WebSockets to display the items that customers are buying in real-time. Gilt's search
functionality also uses Backbone to filter and sort products efficiently
by moving those actions to the client-side.
</p>
<div style="text-align: center;">
<a href="http://www.gilt.com/">
<img width="550" height="444" data-original="docs/images/gilt.jpg" alt="Gilt Groupe" class="example_image" />
</a>
</div>
<h2 id="examples-newsblur">NewsBlur</h2>
<p>
<a href="http://www.newsblur.com">NewsBlur</a> is an RSS feed reader and
social news network with a fast and responsive UI that feels like a
native desktop app. Backbone.js was selected for
<a href="http://www.ofbrooklyn.com/2012/11/13/backbonification-migrating-javascript-to-backbone/">a major rewrite and transition from spaghetti code</a>
because of its powerful yet simple feature set, easy integration, and large
community. If you want to poke around under the hood, NewsBlur is also entirely
<a href="http://github.com/samuelclay/NewsBlur">open-source</a>.
</p>
<div style="text-align: center;">
<a href="http://newsblur.com">
<img width="510" height="340" data-original="docs/images/newsblur.jpg" alt="Newsblur" class="example_retina" />
</a>
</div>
<h2 id="examples-wordpress">WordPress.com</h2>
<p>
<a href="http://wordpress.com/">WordPress.com</a> is the software-as-a-service
version of <a href="http://wordpress.org">WordPress</a>. It uses Backbone.js
Models, Collections, and Views in its
<a href="http://en.blog.wordpress.com/2012/05/25/notifications-refreshed/">Notifications system</a>. Backbone.js was selected
because it was easy to fit into the structure of the application, not the
other way around. <a href="http://automattic.com">Automattic</a>
(the company behind WordPress.com) is integrating Backbone.js into the
Stats tab and other features throughout the homepage.
</p>
<div style="text-align: center;">
<a href="http://wordpress.com/">
<img width="550" height="387" data-original="docs/images/wpcom-notifications.png" alt="WordPress.com Notifications"
title="WordPress.com Notifications" class="example_image" />
</a>
</div>
<h2 id="examples-foursquare">Foursquare</h2>
<p>
Foursquare is a fun little startup that helps you meet up with friends,
discover new places, and save money. Backbone Models are heavily used in
the core JavaScript API layer and Views power many popular features like
the <a href="https://foursquare.com">homepage map</a> and
<a href="https://foursquare.com/seriouseats/list/the-best-doughnuts-in-ny">lists</a>.
</p>
<div style="text-align: center;">
<a href="http://foursquare.com">
<img width="550" height="427" data-original="docs/images/foursquare.png" alt="Foursquare" class="example_image" />
</a>
</div>
<h2 id="examples-bitbucket">Bitbucket</h2>
<p>
<a href="http://www.bitbucket.org">Bitbucket</a> is a free source code hosting
service for Git and Mercurial. Through its models and collections,
Backbone.js has proved valuable in supporting Bitbucket's
<a href="https://api.bitbucket.org">REST API</a>, as well as newer
components such as in-line code comments and approvals for pull requests.
Mustache templates provide server and client-side rendering, while a custom
<a href="https://developers.google.com/closure/library/">Google Closure</a>
inspired life-cycle for widgets allows Bitbucket to decorate existing DOM
trees and insert new ones.
</p>
<div style="text-align: center;">
<a href="http://www.bitbucket.org">
<img width="550" height="356" data-original="docs/images/bitbucket.png" alt="Bitbucket" class="example_image" />
</a>
</div>
<h2 id="examples-disqus">Disqus</h2>
<p>
<a href="http://www.disqus.com">Disqus</a> chose Backbone.js to power the
latest version of their commenting widget. Backbone&rsquo;s small
footprint and easy extensibility made it the right choice for Disqus&rsquo;
distributed web application, which is hosted entirely inside an iframe and
served on thousands of large web properties, including IGN, Wired, CNN, MLB, and more.
</p>
<div style="text-align: center;">
<a href="http://www.disqus.com">
<img width="550" height="454" data-original="docs/images/disqus.png" alt="Disqus" class="example_image" />
</a>
</div>
<h2 id="examples-khan-academy">Khan Academy</h2>
<p>
<a href="http://www.khanacademy.org">Khan Academy</a> is on a mission to
provide a free world-class education to anyone anywhere. With thousands of
videos, hundreds of JavaScript-driven exercises, and big plans for the
future, Khan Academy uses Backbone to keep frontend code modular and organized.
User profiles and goal setting are implemented with Backbone,
<a href="http://jquery.com/">jQuery</a> and
<a href="http://handlebarsjs.com/">Handlebars</a>, and most new feature
work is being pushed to the client side, greatly increasing the quality of
<a href="https://github.com/Khan/khan-api/">the API</a>.
</p>
<div style="text-align: center;">
<a href="http://www.khanacademy.org">
<img width="550" height="454" data-original="docs/images/khan-academy.png" alt="Khan Academy" class="example_image" />
</a>
</div>
<h2 id="examples-do">Do</h2>
<p>
<a href="http://do.com">Do</a> is a social productivity app that makes it
easy to work on tasks, track projects, and take notes with your team.
The <a href="http://do.com">Do.com</a> web application was built from the
ground up to work seamlessly on your smartphone, tablet and computer. The
team used Backbone, <a href="http://coffeescript.org/">CoffeeScript</a> and <a href="http://handlebarsjs.com/">Handlebars</a> to build a full-featured
app in record time and rolled their own extensions for complex navigation
and model sync support.
</p>
<div style="text-align: center;">
<a href="http://do.com">
<img width="550" height="425" data-original="docs/images/do.png" alt="Do" class="example_image" />
</a>
</div>
<h2 id="examples-irccloud">IRCCloud</h2>
<p>
<a href="http://irccloud.com/">IRCCloud</a>
is an always-connected IRC client that you use in your
browser &mdash; often leaving it open all day in a tab.
The sleek web interface communicates with an
Erlang backend via websockets and the
<a href="https://github.com/irccloud/irccloud-tools/wiki/API-Overview">IRCCloud API</a>.
It makes heavy use of Backbone.js events, models, views and routing to keep
your IRC conversations flowing in real time.
</p>
<div style="text-align: center;">
<a href="http://irccloud.com/">
<img width="550" height="392" data-original="docs/images/irccloud.png" alt="IRCCloud" class="example_image" />
</a>
</div>
<h2 id="examples-pitchfork">Pitchfork</h2>
<p>
<a href="http://pitchfork.com/">Pitchfork</a> uses Backbone.js to power
its site-wide audio player, <a href="http://pitchfork.com/tv/">Pitchfork.tv</a>,
location routing, a write-thru page fragment cache, and more. Backbone.js
(and <a href="http://underscorejs.org/">Underscore.js</a>) helps the team
create clean and modular components,
move very quickly, and focus on the site, not the spaghetti.
</p>
<div style="text-align: center;">
<a href="http://pitchfork.com/">
<img width="550" height="428" data-original="docs/images/pitchfork.png" alt="Pitchfork" class="example_image" />
</a>
</div>
<h2 id="examples-spin">Spin</h2>
<p>
<a href="http://spin.com/">Spin</a> pulls in the
<a href="http://www.spin.com/news">latest news stories</a> from
their internal API onto their site using Backbone models and collections, and a
custom <tt>sync</tt> method. Because the music should never stop playing,
even as you click through to different "pages", Spin uses a Backbone router
for navigation within the site.
</p>
<div style="text-align: center;">
<a href="http://spin.com/">
<img width="550" height="543" data-original="docs/images/spin.png" alt="Spin" class="example_image" />
</a>
</div>
<h2 id="examples-walmart">Walmart Mobile</h2>
<p>
<a href="http://www.walmart.com/">Walmart</a> used Backbone.js to create the new version
of <a href="http://mobile.walmart.com/r/phoenix">their mobile web application</a> and
created two new frameworks in the process.
<a href="http://walmartlabs.github.com/thorax/">Thorax</a> provides mixins, inheritable
events, as well as model and collection view bindings that integrate directly with
<a href="http://handlebarsjs.com/">Handlebars</a> templates.
<a href="http://walmartlabs.github.com/lumbar/">Lumbar</a> allows the application to be
split into modules which can be loaded on demand, and creates platform specific builds
for the portions of the web application that are embedded in Walmart's native Android
and iOS applications.
</p>
<div style="text-align: center;">
<a href="http://mobile.walmart.com/r/phoenix">
<img width="256" height="500" data-original="docs/images/walmart-mobile.png" alt="Walmart Mobile" class="example_image" />
</a>
</div>
<h2 id="examples-groupon">Groupon Now!</h2>
<p>
<a href="http://www.groupon.com/now">Groupon Now!</a> helps you find
local deals that you can buy and use right now. When first developing
the product, the team decided it would be AJAX heavy with smooth transitions
between sections instead of full refreshes, but still needed to be fully
linkable and shareable. Despite never having used Backbone before, the
learning curve was incredibly quick &mdash; a prototype was hacked out in an
afternoon, and the team was able to ship the product in two weeks.
Because the source is minimal and understandable, it was easy to
add several Backbone extensions for Groupon Now!: changing the router
to handle URLs with querystring parameters, and adding a simple
in-memory store for caching repeated requests for the same data.
</p>
<div style="text-align: center;">
<a href="http://www.groupon.com/now">
<img width="550" height="466" data-original="docs/images/groupon.png" alt="Groupon Now!" class="example_image" />
</a>
</div>
<h2 id="examples-basecamp">Basecamp</h2>
<p>
<a href="http://37signals.com/">37Signals</a> chose Backbone.js to create
the <a href="http://basecamp.com/calendar">calendar feature</a> of its
popular project management software <a href="http://basecamp.com/">Basecamp</a>.
The Basecamp Calendar uses Backbone.js models and views in conjunction with the
<a href="https://github.com/sstephenson/eco">Eco</a> templating system to
present a polished, highly interactive group scheduling interface.
</p>
<div style="text-align: center;">
<a href="http://basecamp.com/calendar">
<img width="530" height="380" data-original="docs/images/basecamp-calendar.jpg" alt="Basecamp Calendar" class="example_image" />
</a>
</div>
<h2 id="examples-slavery-footprint">Slavery Footprint</h2>
<p>
<a href="http://slaveryfootprint.org/survey">Slavery Footprint</a>
allows consumers to visualize how their consumption habits are
connected to modern-day slavery and provides them with an opportunity
to have a deeper conversation with the companies that manufacture the
goods they purchased.
Based in Oakland, California, the Slavery Footprint team works to engage
individuals, groups, and businesses to build awareness for and create
deployable action against forced labor, human trafficking, and modern-day
slavery through online tools, as well as off-line community education and
mobilization programs.
</p>
<div style="text-align: center;">
<a href="http://slaveryfootprint.org/survey">
<img width="550" height="394" data-original="docs/images/slavery-footprint.png" alt="Slavery Footprint" class="example_image" />
</a>
</div>
<h2 id="examples-stripe">Stripe</h2>
<p>
<a href="https://stripe.com">Stripe</a> provides an API for accepting
credit cards on the web. Stripe's
<a href="https://manage.stripe.com">management interface</a> was recently
rewritten from scratch in Coffeescript using Backbone.js as the primary
framework, <a href="https://github.com/sstephenson/eco">Eco</a> for templates, <a href="http://sass-lang.com/">Sass</a> for stylesheets, and <a href="https://github.com/sstephenson/stitch">Stitch</a> to package
everything together as <a href="http://commonjs.org/">CommonJS</a> modules. The new app uses
<a href="https://stripe.com/docs/api">Stripe's API</a> directly for the
majority of its actions; Backbone.js models made it simple to map
client-side models to their corresponding RESTful resources.
</p>
<div style="text-align: center;">
<a href="https://stripe.com">
<img width="555" height="372" data-original="docs/images/stripe.png" alt="Stripe" class="example_image" />
</a>
</div>
<h2 id="examples-airbnb">Airbnb</h2>
<p>
<a href="http://airbnb.com">Airbnb</a> uses Backbone in many of its products.
It started with <a href="http://m.airbnb.com">Airbnb Mobile Web</a>
(built in six weeks by a team of three) and has since grown to
<a href="https://www.airbnb.com/wishlists/popular">Wish Lists</a>,
<a href="http://www.airbnb.com/match">Match</a>,
<a href="http://www.airbnb.com/s/">Search</a>, Communities, Payments, and
Internal Tools.
</p>
<div style="text-align: center;">
<a href="http://m.airbnb.com/">
<img width="500" height="489" data-original="docs/images/airbnb.png" alt="Airbnb" class="example_image" />
</a>
</div>
<h2 id="examples-diaspora">Diaspora</h2>
<p>
<a href="http://www.joindiaspora.com/">Diaspora</a> is a distributed social
network, formed from a number of independently operated <i>pods</i>.
You own your personal data, and control with whom you share.
All of Diaspora is <a href="https://github.com/diaspora/diaspora">open-source</a>
code, built with <a href="http://rubyonrails.org/">Rails</a> and Backbone.js.
</p>
<div style="text-align: center;">
<a href="http://www.joindiaspora.com/">
<img width="550" height="394" data-original="docs/images/diaspora.png" alt="Diaspora" class="example_image" />
</a>
</div>
<h2 id="examples-soundcloud">SoundCloud Mobile</h2>
<p>
<a href="http://soundcloud.com">SoundCloud</a> is the leading sound sharing
platform on the internet, and Backbone.js provides the foundation for
<a href="http://m.soundcloud.com">SoundCloud Mobile</a>. The project uses
the public SoundCloud <a href="http://soundcloud.com/developers">API</a>
as a data source (channeled through a nginx proxy),
<a href="http://api.jquery.com/category/plugins/templates/">jQuery templates</a>
for the rendering, <a href="http://docs.jquery.com/Qunit">Qunit
</a> and <a href="http://www.phantomjs.org/">PhantomJS</a> for
the testing suite. The JS code, templates and CSS are built for the
production deployment with various Node.js tools like
<a href="https://github.com/dsimard/ready.js">ready.js</a>,
<a href="https://github.com/mde/jake">Jake</a>,
<a href="https://github.com/tmpvar/jsdom">jsdom</a>.
The <b>Backbone.History</b> was modified to support the HTML5 <tt>history.pushState</tt>.
<b>Backbone.sync</b> was extended with an additional SessionStorage based cache
layer.
</p>
<div style="text-align: center;">
<a href="http://m.soundcloud.com">
<img width="266" height="500" data-original="docs/images/soundcloud.png" alt="SoundCloud" class="example_image" />
</a>
</div>
<h2 id="examples-artsy">Art.sy</h2>
<p>
<a href="http://art.sy">Art.sy</a> is a place to discover art you'll
love. Art.sy is built on Rails, using
<a href="https://github.com/intridea/grape">Grape</a> to serve a robust
<a href="http://art.sy/api">JSON API</a>. The main site is a single page
app written in Coffeescript and uses Backbone to provide structure around
this API. An admin panel and partner CMS have also been extracted into
their own API-consuming Backbone projects.
</p>
<div style="text-align: center;">
<a href="http://art.sy">
<img width="550" height="550" data-original="docs/images/artsy.png" alt="Art.sy" class="example_image" />
</a>
</div>
<h2 id="examples-pandora">Pandora</h2>
<p>
When <a href="http://www.pandora.com/newpandora">Pandora</a> redesigned
their site in HTML5, they chose Backbone.js to help
manage the user interface and interactions. For example, there's a model
that represents the "currently playing track", and multiple views that
automatically update when the current track changes. The station list is a
collection, so that when stations are added or changed, the UI stays up to date.
</p>
<div style="text-align: center;">
<a href="http://www.pandora.com/newpandora">
<img width="476" height="359" data-original="docs/images/pandora.png" alt="Pandora" class="example_image" />
</a>
</div>
<h2 id="examples-inkling">Inkling</h2>
<p>
<a href="http://inkling.com/">Inkling</a> is a cross-platform way to
publish interactive learning content.
<a href="https://www.inkling.com/read/">Inkling for Web</a> uses Backbone.js
to make hundreds of complex books — from student textbooks to travel guides and
programming manuals — engaging and accessible on the web. Inkling supports
WebGL-enabled 3D graphics, interactive assessments, social sharing,
and a system for running practice code right
in the book, all within a single page Backbone-driven app. Early on, the
team decided to keep the site lightweight by using only Backbone.js and
raw JavaScript. The result? Complete source code weighing in at a mere
350kb with feature-parity across the iPad, iPhone and web clients.
Give it a try with
<a href="https://www.inkling.com/read/javascript-definitive-guide-david-flanagan-6th/chapter-4/function-definition-expressions">this excerpt from JavaScript: The Definitive Guide</a>.
</p>
<div style="text-align: center;">
<a href="http://inkling.com">
<img width="550" height="361" data-original="docs/images/inkling.png" alt="Inkling" class="example_image" />
</a>
</div>
<h2 id="examples-code-school">Code School</h2>
<p>
<a href="http://www.codeschool.com">Code School</a> courses teach people
about various programming topics like <a href="http://coffeescript.org">CoffeeScript</a>, CSS, Ruby on Rails,
and more. The new Code School course
<a href="http://coffeescript.codeschool.com/levels/1/challenges/1">challenge page</a>
is built from the ground up on Backbone.js, using
everything it has to offer: the router, collections, models, and complex
event handling. Before, the page was a mess of <a href="http://jquery.com/">jQuery</a> DOM manipulation
and manual Ajax calls. Backbone.js helped introduce a new way to
think about developing an organized front-end application in Javascript.
</p>
<div style="text-align: center;">
<a href="http://www.codeschool.com">
<img width="550" height="482" data-original="docs/images/code-school.png" alt="Code School" class="example_image" />
</a>
</div>
<h2 id="examples-cloudapp">CloudApp</h2>
<p>
<a href="http://getcloudapp.com">CloudApp</a> is simple file and link
sharing for the Mac. Backbone.js powers the web tools
which consume the <a href="http://developer.getcloudapp.com">documented API</a>
to manage Drops. Data is either pulled manually or pushed by
<a href="http://pusher.com">Pusher</a> and fed to
<a href="http://github.com/janl/mustache.js">Mustache</a> templates for
rendering. Check out the <a href="http://cloudapp.github.com/engine">annotated source code</a>
to see the magic.
</p>
<div style="text-align: center;">
<a href="http://getcloudapp.com">
<img width="550" height="426" data-original="docs/images/cloudapp.png" alt="CloudApp" class="example_image" />
</a>
</div>
<h2 id="examples-seatgeek">SeatGeek</h2>
<p>
<a href="http://seatgeek.com">SeatGeek</a>'s stadium ticket maps were originally
developed with <a href="http://prototypejs.org/">Prototype.js</a>. Moving to Backbone.js and <a href="http://jquery.com/">jQuery</a> helped organize
a lot of the UI code, and the increased structure has made adding features
a lot easier. SeatGeek is also in the process of building a mobile
interface that will be Backbone.js from top to bottom.
</p>
<div style="text-align: center;">
<a href="http://seatgeek.com">
<img width="550" height="455" data-original="docs/images/seatgeek.png" alt="SeatGeek" class="example_image" />
</a>
</div>
<h2 id="examples-easel">Easel</h2>
<p>
<a href="http://easel.io">Easel</a> is an in-browser, high fidelity web
design tool that integrates with your design and development
process. The Easel team uses CoffeeScript, Underscore.js and Backbone.js for
their <a href="http://easel.io/demo">rich visual editor</a> as well as other
management functions throughout the site. The structure of Backbone allowed
the team to break the complex problem of building a visual editor into
manageable components and still move quickly.
</p>
<div style="text-align: center;">
<a href="http://easel.io">
<img width="550" height="395" data-original="docs/images/easel.png" alt="Easel" class="example_image" />
</a>
</div>
<h2 id="examples-prose">Prose</h2>
<p>
<a href="http://prose.io">Prose</a> is a content editor for GitHub,
optimized for managing websites built with
<a href="http://jekyllrb.com/">Jekyll</a> and Github Pages. Prose is
itself implemented as a static Jekyll site, using Backbone.js to render
the views and handle the routes, as well as
<a href="http://github.com/michael/github">Github.js</a>, a small data
abstraction layer for manipulating files directly on Github. Read more in the
<a href="http://developmentseed.org/blog/2012/june/25/prose-a-content-editor-for-github/">official introduction post</a>,
or <a href="https://github.com/prose/prose">take a look at the source code</a>.
</p>
<div style="text-align: center;">
<a href="http://prose.io">
<img width="550" height="447" data-original="docs/images/prose.png" alt="Prose" class="example_image" />
</a>
</div>
<h2 id="examples-jolicloud">Jolicloud</h2>
<p>
<a href="http://www.jolicloud.com/">Jolicloud</a> is an open and independent