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/
index.html
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index.html
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<!DOCTYPE HTML>
<html>
<head>
<meta http-equiv="content-type" content="text/html;charset=UTF-8" />
<meta http-equiv="X-UA-Compatible" content="chrome=1">
<title>Backbone.js</title>
<style>
body {
font-size: 14px;
line-height: 22px;
font-family: Helvetica Neue, Helvetica, Arial;
background: #f4f4f4 url(docs/images/background.png);
}
.interface {
font-family: "Lucida Grande", "Lucida Sans Unicode", Helvetica, Arial, sans-serif !important;
}
div#sidebar {
background: #fff;
position: fixed;
top: 0; left: 0; bottom: 0;
width: 200px;
overflow-y: auto;
overflow-x: hidden;
padding: 15px 0 30px 30px;
border-right: 1px solid #ddd;
box-shadow: 0 0 20px #ccc; -webkit-box-shadow: 0 0 20px #ccc; -moz-box-shadow: 0 0 20px #ccc;
}
a.toc_title, a.toc_title:visited {
display: block;
color: black;
font-weight: bold;
margin-top: 15px;
}
div.toc_title:hover {
text-decoration: underline;
}
ul.toc_section {
font-size: 11px;
line-height: 14px;
margin: 5px 0 0 0;
padding-left: 0px;
list-style-type: none;
font-family: Lucida Grande;
}
.toc_section li {
cursor: pointer;
margin: 0 0 3px 0;
}
.toc_section li a {
color: black;
}
div.container {
position: relative;
width: 550px;
margin: 40px 0 50px 260px;
}
div.run {
position: absolute;
right: 15px;
width: 26px; height: 18px;
background: url('docs/images/arrows.png') no-repeat -26px 0;
}
div.run:active {
background-position: -51px 0;
}
p, div.container ul {
margin: 20px 0;
width: 550px;
}
div.container ul {
list-style: circle;
font-size: 12px;
padding-left: 15px;
}
a, a:visited {
color: #444;
text-decoration: none;
}
a:active, a:hover {
color: #000;
text-decoration: underline;
}
a img {
border: 0;
}
h1, h2, h3, h4, h5, h6 {
padding-top: 20px;
}
h2 {
font-size: 20px;
}
b.header {
font-size: 16px;
line-height: 30px;
}
span.alias {
font-size: 14px;
font-style: italic;
margin-left: 20px;
}
table {
margin: 15px 0 0; padding: 0;
}
tr, td {
margin: 0; padding: 0;
}
td {
padding: 0px 15px 5px 0;
}
code, pre, tt {
font-family: Monaco, Consolas, "Lucida Console", monospace;
font-size: 12px;
line-height: 18px;
}
tt {
padding: 0px 3px;
background: #fff;
border: 1px solid #ddd;
zoom: 1;
}
code {
margin-left: 20px;
}
pre {
font-size: 12px;
padding: 2px 0 2px 15px;
border: 4px solid #bbb; border-top: 0; border-bottom: 0;
margin: 0px 0 30px;
}
</style>
</head>
<body>
<div id="sidebar" class="interface">
<a class="toc_title" href="#">
Backbone.js
</a>
<a class="toc_title" href="#Introduction">
Introduction
</a>
<a class="toc_title" href="#Events">
Events
</a>
<ul class="toc_section">
<li>– <a href="#Events-bind">bind</a></li>
<li>– <a href="#Events-unbind">unbind</a></li>
<li>– <a href="#Events-trigger">trigger</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</a></li>
<li>– <a href="#Model-get">get</a></li>
<li>– <a href="#Model-set">set</a></li>
<li>– <a href="#Model-unset">unset</a></li>
<li>– <a href="#Model-id">id</a></li>
<li>– <a href="#Model-cid">cid</a></li>
<li>– <a href="#Model-attributes">attributes</a></li>
<li>- <a href="#Model-toJSON">toJSON</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-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-constructor">constructor</a></li>
<li>– <a href="#Collection-models">models</a></li>
<li>– <a href="#Collection-Underscore-Methods"><b>Underscore Methods (24)</b></a></li>
<li>– <a href="#Collection-add">add</a></li>
<li>– <a href="#Collection-remove">remove</a></li>
<li>– <a href="#Collection-get">get</a></li>
<li>– <a href="#Collection-getByCid">getByCid</a></li>
<li>– <a href="#Collection-at">at</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="#Model-url">url</a></li>
<li>– <a href="#Collection-refresh">refresh</a></li>
<li>– <a href="#Collection-fetch">fetch</a></li>
<li>– <a href="#Collection-create">create</a></li>
</ul>
<a class="toc_title" href="#Sync">
Sync
</a>
<ul class="toc_section">
<li>– <a href="#Sync">Backbone.sync</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</a></li>
<li>– <a href="#View-el">el</a></li>
<li>– <a href="#View-jQuery">$ (jQuery)</a></li>
<li>– <a href="#View-render">render</a></li>
<li>– <a href="#View-make">make</a></li>
<li>– <a href="#View-handleEvents">handleEvents</a></li>
</ul>
<a class="toc_title" href="#changelog">
Change Log
</a>
</div>
<div class="container">
<p>
<img style="width: 385px; height: 126px;" src="docs/images/backbone.png" alt="Backbone.js" />
</p>
<p>
<a href="http://github.com/documentcloud/backbone/">Backbone</a>
supplies structure to JavaScript-heavy 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 application 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.html">test suite</a>.
</p>
<p>
<i>
Backbone is an open-source component of
<a href="http://documentcloud.org/">DocumentCloud</a>.
</i>
</p>
<h2 id="downloads">
Downloads & 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 href="backbone.js">Development Version (0.1.0)</a></td>
<td><i>21kb, Uncompressed with Comments</i></td>
</tr>
<tr>
<td><a href="backbone-min.js">Production Version (0.1.0)</a></td>
<td><i>2kb, Packed and Gzipped</i></td>
</tr>
</table>
<p>
Backbone's only hard dependency is
<a href="http://documentcloud.github.com/underscore/">Underscore.js</a>.
For RESTful persistence, and DOM manipulation with
<a href="#View">Backbone.View</a>,
it's highly recommended to include <a href="http://jquery.com">jQuery</a>,
and <a href="http://www.json.org/json2.js">json2.js</a>
(both of which you may already have on the page).
</p>
<h2 id="Introduction">Introduction</h2>
<p>
When working on a web application that involved 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 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 data receive the
event, causing them to re-render. 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
— when the model changes, the views simply update themselves.
</p>
<p>
<i>How is this different than
<a href="http://www.sproutcore.com/">SproutCore</a> or
<a href="http://cappuccino.org/">Cappuccino</a>?
</i>
</p>
<p>
This question is frequently asked, and all three projects apply general
<a href="http://en.wikipedia.org/wiki/Model–View–Controller">Model-View-Controller</a>
principles to JavaScript applications. However, there isn't much basis
for comparsion. SproutCore and Cappuccino provide rich UI widgets, vast
core libraries, and determine the structure of your HTML for you.
Loading the "Hello World" of SproutCore includes <i>2.5 megabytes</i> of JavaScript on the
page; the "Hello World" of Cappuccino includes <i>1.7 megabytes</i> of JS and images,
as measured with the Webkit inspector.
Backbone is a <i>2 kilobyte</i> include (packed, gzipped) that provides
just the core concepts of models, events (key-value binding), collections,
views, and persistence. A much closer relative to Backbone is
<a href="http://benpickles.github.com/js-model/">js-model</a>.
</p>
<p>
Many of the examples that follow are runnable. Click the <i>play</i> button
to execute them.
</p>
<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.bind("alert", function(msg) {
alert("Triggered " + msg);
});
object.trigger("alert", "an event");
</pre>
<p id="Events-bind">
<b class="header">bind</b><code>object.bind(event, callback)</code>
<br />
Bind a <b>callback</b> function to an object. The callback will be invoked
whenever the <b>event</b> (specified by an arbitrary string identifier) is fired.
If you have many events on a page, the convention is to use colons to
namespace them: <tt>"poll:start"</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.bind("all", function(eventName) {
object.trigger(eventName);
});
</pre>
<p id="Events-unbind">
<b class="header">unbind</b><code>object.unbind([event], [callback])</code>
<br />
Remove a previously-bound <b>callback</b> function from an object. If no
callback is specified, all callbacks for the <b>event</b> will be
removed. If no event is specified, all bound callbacks on the object
will be removed.
</p>
<pre>
object.unbind("change", onChange); // Removes just the onChange callback.
object.unbind("change"); // Removes all "change" callbacks.
object.unbind(); // Removes all callbacks on object.
</pre>
<p id="Events-trigger">
<b class="header">trigger</b><code>object.trigger(event, [*args])</code>
<br />
Trigger all callbacks for the given <b>event</b>. All subsequent arguments to
<b>trigger</b> will be passed along to the event callbacks.
</p>
<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.bind('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({
author: function() { ... },
allowedToEdit: function(account) { ... },
coordinates: function() { ... }
});
</pre>
<p id="Model-constructor">
<b class="header">constructor</b><code>new Model([attributes])</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.
</p>
<pre>
new Book({
title: "One Thousand and One Nights",
author: "Scheherazade"
});
</pre>
<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 models state, a <tt>"change"</tt> event will be fired, unless
<tt>{silent: true}</tt> is passed as an option.
</p>
<p>
If the model has a <a href="#Model-validate">validate</a> method,
it will be validated before the attributes are set, and no changes will
occur if the validation fails.
</p>
<pre>
note.set({title: "October 12", content: "Lorem Ipsum Dolor Sit Amet..."});
</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-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-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. Please use <a href="#Model-set">set</a> to update the attributes 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 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.
</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-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>. 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>). Accepts
<tt>success</tt> and <tt>error</tt> callbacks in the options hash, which
are passed <tt>(model, response)</tt> as arguments.
</p>
<p>
In the following example, notice how because the model has never been
saved previously, our overridden version of <tt>Backbone.sync</tt> receives a <tt>"create"</tt> request.
</p>
<pre class="runnable">
Backbone.sync = function(method, model) {
alert(method + ": " + JSON.stringify(model));
};
var book = new Backbone.Model({
title: "The Rough Riders",
author: "Theodore Roosevelt"
});
book.save();
</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>. Accepts
<tt>success</tt> and <tt>error</tt> callbacks in the options hash.
</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 attributes that are about to be updated.
If the model and attributes are valid, don't return anything from <b>validate</b>;
if the attributes 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. <tt>set</tt> and
<tt>save</tt> will not continue if <b>validate</b> returns an error.
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.bind("error", function(model, error) {
alert(model.get("title") + " " + error);
});
one.set({
start: 15,
end: 10
});
</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]/[id]"</tt>.
</p>
<p>
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>"/notes"</tt>,
would have this URL: <tt>"/notes/101"</tt>
</p>
<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.
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>
<pre>
book.bind("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.bind("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 callbacks to be notified
when any model in the collection is changed, 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 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-constructor">
<b class="header">constructor</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> function
may be included as an option.
</p>
<pre>
window.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-Underscore-Methods">
<b class="header">Underscore Methods (24)</b>
<br />
Backbone proxies to <b>Underscore.js</b> to provide 24 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…
</p>
<ul>
<li><a href="http://documentcloud.github.com/underscore/#each">forEach (each)</a></li>
<li><a href="http://documentcloud.github.com/underscore/#map">map</a></li>
<li><a href="http://documentcloud.github.com/underscore/#reduce">reduce (foldl, inject)</a></li>
<li><a href="http://documentcloud.github.com/underscore/#reduceRight">reduceRight (foldr)</a></li>
<li><a href="http://documentcloud.github.com/underscore/#detect">find (detect)</a></li>
<li><a href="http://documentcloud.github.com/underscore/#select">filter (select)</a></li>
<li><a href="http://documentcloud.github.com/underscore/#reject">reject</a></li>
<li><a href="http://documentcloud.github.com/underscore/#all">every (all)</a></li>
<li><a href="http://documentcloud.github.com/underscore/#any">some (any)</a></li>
<li><a href="http://documentcloud.github.com/underscore/#include">include</a></li>
<li><a href="http://documentcloud.github.com/underscore/#invoke">invoke</a></li>
<li><a href="http://documentcloud.github.com/underscore/#max">max</a></li>
<li><a href="http://documentcloud.github.com/underscore/#min">min</a></li>
<li><a href="http://documentcloud.github.com/underscore/#sortBy">sortBy</a></li>
<li><a href="http://documentcloud.github.com/underscore/#sortedIndex">sortedIndex</a></li>
<li><a href="http://documentcloud.github.com/underscore/#toArray">toArray</a></li>
<li><a href="http://documentcloud.github.com/underscore/#size">size</a></li>
<li><a href="http://documentcloud.github.com/underscore/#first">first</a></li>
<li><a href="http://documentcloud.github.com/underscore/#rest">rest</a></li>
<li><a href="http://documentcloud.github.com/underscore/#last">last</a></li>
<li><a href="http://documentcloud.github.com/underscore/#without">without</a></li>
<li><a href="http://documentcloud.github.com/underscore/#indexOf">indexOf</a></li>
<li><a href="http://documentcloud.github.com/underscore/#lastIndexOf">lastIndexOf</a></li>
<li><a href="http://documentcloud.github.com/underscore/#isEmpty">isEmpty</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.
</p>
<pre class="runnable">
var Ship = Backbone.Model;
var ships = new Backbone.Collection;
ships.bind("add", function(ship) {
alert("Ahoy " + ship.get("name") + "!");
});
ships.add([
new Ship({name: "Flying Dutchman"}),
new Ship({name: "Black Pearl"})
]);
</pre>
<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.
</p>
<p id="Collection-get">
<b class="header">get</b><code>collection.get(id)</code>
<br />
Get a model from a collection, specified by <b>id</b>.
</p>
<pre>
var book = Library.get(110);
</pre>
<p id="Collection-getByCid">
<b class="header">getByCid</b><code>collection.getByCid(cid)</code>
<br />
Get a model from a collection, specified by client id. The client id
is the <tt>.cid</tt> property of the model, automatically assigned whenever
a model is created. Useful for models which have not yet been saved to
the server, and do not yet have true ids.
</p>
<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-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> function on 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>.
Comparator functions take a model and return a numeric or string value
by which the model should be ordered relative to others.
</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 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> function
will maintain itself in proper sort order at all times. Triggers the
collection's <tt>"refresh"</tt> event, 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([
new Backbone.Model({name: "Curly"}),
new Backbone.Model({name: "Larry"}),
new Backbone.Model({name: "Moe"})
]);
var names = stooges.pluck("name");
alert(JSON.stringify(names));
</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-refresh">
<b class="header">refresh</b><code>collection.refresh(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>refresh</b> to replace a collection with a new list
of models (or attribute hashes), triggering a single <tt>"refresh"</tt> event
at the end. Pass <tt>{silent: true}</tt> to suppress the <tt>"refresh"</tt> event.
</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,
refreshing 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)</tt> as arguments.
Delegates to <a href="#Sync">Backbone.sync</a>
under the covers, for custom persistence strategies.
</p>
<p>
The server handler for <b>fetch</b> requests should return a JSON list of
models, namespaced under "models": <tt>{"models": [...]}</tt> —
additional information can be returned with the response under different keys.
</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>
Note that <b>fetch</b> should not be used to populate collections on
page load — all models needed at load time should already be
bootstrapped 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>