<div class="intro">
<p>
The Node Utility provides an expressive way to collect, create, and
manipulate DOM nodes. Each `Node` instance represents an underlying
DOM node, and each `NodeList` represents a collection of DOM nodes.
</p>
<p>
In addition to wrapping the basic DOM API and handling cross browser
issues, `Node`s provide convenient methods for managing CSS classes,
setting or animating styles, subscribing to events, updating or
dynamically loading content, and lots more.
</p>
<p>
<strong>Note:</strong> The <em>`Y.get()`, `node.query()`, and
`node.queryAll()` methods have been removed. Use `Y.one()`,
"<a href="{{apiDocs}}/modules/node-deprecated.html">node-deprecated</a>"
module in your `use()` statement to restore them</em>.
</p>
</div>
{{>getting-started}}
<h2 id="node-using">Using Nodes</h2>
<p>
`Node` is the interface for DOM operations in YUI 3. The Node API is
based on the standard DOM API, and provides additional sugar properties
and methods that make common operations easier, and implementation code
more concise. Developers familiar with the standard DOM API will find
Node instances to be very familiar.
</p>
<h3 id="using-node">Getting a Node</h3>
```
// Use Y.one( [css selector string] )
var node = Y.one('#main');
// Or pass an HTML element
var bodyNode = Y.one(document.body);
```
<p>
The simplest way to get a `Node` instance is using your YUI instance's
`one` method. `Y.one` accepts either an existing DOM element or a CSS
selector. If a selector string is used, the first matching element is used.
<a href="#nodelist">NodeLists</a> are also available for working with
collections of `Node`s.
</p>
<p>
<strong>Note:</strong> CSS3 selector support is not included by default
with Node. Add support by including the "selector-css3" module in your
`use()` statement.
</p>
<h3 id="create">Creating Nodes and Modifying Content</h3>
```
// Create a new Node
var item = Y.Node.create('<li id="step3" class="highlight"><em>Profit</em></li>');
// Replace the content in a Node
Y.one("#hello").setContent("<h1>Hello, <em>World</em>!</h1>");
// Append new markup inside a Node
bodyNode.append("<p>This is the end, beautiful friend, the end.</p>");
```
<p>
`Node`s have methods for
<a href="{{apiDocs}}/classes/Node.html#method_append">appending</a>,
<a href="{{apiDocs}}/classes/Node.html#method_prepend">prepending</a>,
<a href="{{apiDocs}}/classes/Node.html#method_setContent">replacing</a>, and
<a href="{{apiDocs}}/classes/Node.html#method_insert">inserting</a>
content. The static method
<a href="{{apiDocs}}/classes/Node.html#method_create">`Y.Node.create()`</a>
is provided to create new `Node`s that you want to work with a bit more
before attaching them to the DOM.
</p>
<p>
As noted in <a href="#node-methods">DOM Methods</a> below, the standard DOM
API methods, such as `appendChild` and `insertBefore` are also available to
manipulate the DOM structure.
</p>
<h3 id="node-properties">Accessing Node Properties</h3>
```
var imgNode = Y.one('#preview');
var labelNode = imgNode.get('nextSibling'); // Node instance
var bigSrc = thumbnail.get('src').slice(0, -4) + '-big.jpg';
imgNode.set('src', bigSrc);
imgNode.set('title', thumbnail.get('title');
labelNode.setContent(thumbnail.get('title'));
```
<p>
Properties of the underlying DOM node are accessed via the `Node`
instance's `set` and `get` methods. For simple property types (strings,
numbers, booleans), these pass directly to/from the underlying node, but
properties that normally return DOM nodes return `Node` instances
instead.
</p>
<h3 id="node-events">DOM Events</h3>
```
Y.one('#demo').on('click', function(e) {
alert('event: ' + e.type + ' target: ' + e.target.get('tagName'));
});
```
<p>
Use the `on` method to add an event listener to a `Node` instance. The
event object passed as the first argument to each listener is an event
facade that, like the Node API, normalizes browser differences and provides
a standard API for working with DOM events based on the W3C standard. All
properties of the event object that would normally return DOM elements
return `Node` instances.
</p>
<p>
For more details, check out <a href="../event/index.html">the Event user
guide</a>.
</p>
<h3 id="node-methods">DOM Methods</h3>
```
var tasklist = Y.one('ul#tasklist');
var item3 = tasklist.appendChild( Y.one('#pending .item-3') );
item3.addClass('highlight');
```
<p>
The `Node` API provides all of the DOM methods you would expect, plus a
few extras to help with common tasks. As with properties and events, any
methods that would normally return DOM nodes instead return `Node`
instances.
</p>
<h3 id="nodelist">Working With Collections of Nodes</h3>
<p>
`NodeList` is the class for working with groups of `Node`s.
</p>
```
var doneTasks = Y.all('#tasklist .completed');
// NodeLists host most Node methods for simple iterative operations
doneTasks.removeClass('highlight');
// or call each() to do more work on each Node
doneTasks.each(function (taskNode) {
taskNode.transition({ opacity: 0 }, function () {
});
});
```
<p>
The `Y.all` method is the simplest way to get a `NodeList`, but throughout
the library, any property or method that would return a collection of HTML
elements will return a `NodeList`.
</p>
```
var nodelist = taskList.get('childNodes');
```
<p>
The `NodeList` provides a `Node`-like interface for manipulating multiple
`Node`s through a single interface. The `NodeList` API is a pared-down
version of the `Node` API for simple operations, plus common `Array`
methods such as
<a href="{{apiDocs}}/classes/NodeList.html#method_slice">`slice()`</a> and
<a href="{{apiDocs}}/classes/NodeList.html#method_pop">`pop()`</a> for
modifying the internal list of wrapped `Node`s, and some general purpose
iteration methods such as
<a href="{{apiDocs}}/classes/NodeList.html#method_each">`each()`</a> and
<a href="{{apiDocs}}/classes/NodeList.html#method_some">`some()`</a>.
</p>
<h3 id="node-query">Query a Node's Descendants</h3>
```
var node = Y.one('#demo');
var firstPara = node.one('p');
if (firstPara) { // might be null
// adds "bar" to the first paragraph descendant of #demo
firstPara.addClass('intro');
}
// adds class "syntax-highlight" to all <pre> descendants of #demo
node.all('pre').addClass('syntax-highlight');
```
<p>
methods for querying their descendants.
</p>
<p>
Using selectors to capture descendants is faster and more convenient than
relying on DOM properties such as `childNodes` and `nextSibling` since you
don't have to worry about working around text nodes or recursing into
element subtrees.
</p>
<p>
Using `one()` and `all()` from a `Node` rather than `Y` can aid performance
the `document`, which will scan a lot more elements.
</p>
<p>
For more information on selector queries, see the following W3C
specifications:
</p>
<ul>
<li><a href="http://www.w3.org/TR/css3-selectors/">CSS Level 3 Selectors</a></li>
<li><a href="http://www.w3.org/TR/selectors-API/">Selectors API</a></li>
</ul>
<p>
<strong>Note:</strong> CSS3 selector support is not included by default
with Node, you will need to include the "selector-css3" module for CSS3
support.
</p>
<h2 id="node-aria">ARIA Support</h2>
<p>
The Node interface has support for <a
href="http://www.w3.org/TR/wai-aria/">ARIA</a>. When used with Node's
built-in support for CSS selector queries, it is easy to both apply and
manage a Node's <a href="http://www.w3.org/TR/wai-aria/#roles">roles</a>,
<a href="http://www.w3.org/TR/wai-aria/#supportedState">states and
properties</a>.
<p>
<p>
The ARIA Roles, States and Properties enhance the semantics of HTML,
allowing developers to more accurately describe the intended purpose of a
region of a page, or a DHTML widget, thereby improving the user experience
for users of assistive technology, such as screen readers.
</p>
<p>
Apply any of the ARIA Roles, States and Properties via the `set` method.
For example, to apply the role of <a
href="http://www.w3.org/TR/wai-aria/#toolbar">`toolbar`</a> to a `<div>`
with an id of "toolbar":
</p>
```
var node = Y.one('#toolbar').set('role', 'toolbar');
```
<p>
Node's built-in support for CSS selector queries, method chaining, and
ability to set multiple attributes on a single Node instance makes it
especially easy to apply the ARIA Roles, States, and Properties when
building DHTML widgets with a large subtree. For example, when building a
menubar widget it is necessary to apply a role of
<a href="http://www.w3.org/TR/wai-aria/#menubar">`menubar`</a> to the root
DOM element representing the menubar, and the role of
<a href="http://www.w3.org/TR/wai-aria/#menu">`menu`</a> to the root DOM
element representing each submenu. Additionally, as each submenu is hidden
by default, the
<a href="http://www.w3.org/TR/wai-aria/#aria-">`aria-hidden`</a> state will
need to be applied to each submenu as well. The Node interface makes it
possible to do all of this in one line of code:
</p>
```
Y.one('#root').set('role', 'menubar').all('.menu').setAttrs({ role: 'menu', 'aria-hidden': true });
```
<h2 id="node-migration">Migration Table</h2>
<p>
The following table is included to help users migrating from YUI 2. Most
of the functionality from `YAHOO.util.Dom` is available via `Node`.
</p>
<p>
<strong>Note</strong> In the snippets below, `myNode` is an instance of
`Node`. Methods that normally would return DOM nodes now return Node
instances.
</p>
<table class="yui-table">
<thead>
<tr>
<th>2.x `YAHOO.util.???`</th>
<th>3.0</th>
</tr>
</thead>
<tbody>
<tr>
<td>
```
Dom.get('elementId');
```
</td>
<td>
```
Y.one('#elementId');
```
</td>
</tr>
<tr>
<td>
```
Dom.getElementsBy(someFilterFunction);
```
</td>
<td>
```
myNode.all('selectorString');
```
</td>
</tr>
<tr>
<td>
```
Dom.getElementsByClassName('highlight');
```
</td>
<td>
```
myNode.all('.highlight');
```
</td>
</tr>
<tr>
<td>
```
Dom.getChildren(el);
```
</td>
<td>
```
myNode.get('children');
```
</td>
</tr>
<tr>
<td>
```
Dom.getChildrenBy(someFilterFunction);
```
</td>
<td>
```
myNode.all('selectorString');
```
</td>
</tr>
<tr>
<td>
```
Dom.getFirstChild(parentEl);
```
</td>
<td>
```
myNode.one('*');
```
</td>
</tr>
<tr>
<td>
```
Dom.getFirstChildBy(someFilterFunction);
```
</td>
<td>
```
myNode.one('> selectorString');
```
</td>
</tr>
<tr>
<td>
```
Dom.getLastChild(el);
Dom.getLastChildBy(someFilterFunction);
```
</td>
<td>
```
myNode.get('children').slice(-1).item(0);
// OR target the node with a selector
myNode.one('> selector:last-of-type');
```
</td>
</tr>
<tr>
<td>
```
Dom.getNextSibling(el);
Dom.getNextSiblingBy(someFilterFunction);
Dom.getPreviousSiblingBy(someFilterFunction);
```
</td>
<td>
```
myNode.next();
myNode.next('selectorString');
myNode.previous('selectorString');
```
</td>
</tr>
<tr>
<td>
```
Dom.getAncestorBy(someFilterFunction);
Dom.getAncestorByClassName('highlight');
Dom.getAncestorByTagName('pre');
```
</td>
<td>
```
myNode.ancestor(someFilterFunction);
myNode.ancestor('.highlight');
myNode.ancestor('pre');
```
</td>
</tr>
<tr>
<td>
```
Dom.isAncestor(ancestorEl, el);
```
</td>
<td>
```
ancestorNode.contains(myNode);
```
</td>
</tr>
<tr>
<td>
```
Dom.insertAfter(el, afterEl);
Dom.insertBefore(el, beforeNode);
```
</td>
<td>
```
afterNode.insert(myNode, 'after');
beforeNode.insert(myNode, 'before');
```
</td>
</tr>
<tr>
<td>
```
Dom.addClass('highlight');
```
</td>
<td>
```
myNode.addClass('highlight');
```
</td>
</tr>
<tr>
<td>
```
Dom.removeClass(el, 'highlight');
```
</td>
<td>
```
myNode.removeClass('highlight');
```
</td>
</tr>
<tr>
<td>
```
Dom.replaceClass(el, 'high', 'low');
```
</td>
<td>
```
myNode.replaceClass('high', 'low');
```
</td>
</tr>
<tr>
<td>
```
Dom.hasClass(el, 'highlight');
```
</td>
<td>
```
myNode.hasClass('highlight');
```
</td>
</tr>
<tr>
<td>
```
Dom.getStyle(el, 'backgroundColor');
```
</td>
<td>
```
myNode.getStyle('backgroundColor');
```
</td>
</tr>
<tr>
<td>
```
Dom.setStyle(el, 'borderColor', '#C0FFEE');
```
</td>
<td>
```
myNode.setStyle('borderColor', '#C0FFEE');
```
</td>
</tr>
<tr>
<td>
```
Dom.getXY(el);
Dom.getX(el);
Dom.getY(el);
```
</td>
<td>
```
myNode.getXY();
myNode.getX();
myNode.getY();
```
</td>
</tr>
<tr>
<td>
```
Dom.setXY(el, [ 500, 300 ]);
Dom.setX(el, 500);
Dom.setY(el, 300);
```
</td>
<td>
```
myNode.setXY([ 500, 300 ]);
myNode.setX(500);
myNode.setY(300);
```
</td>
</tr>
<tr>
<td>
```
Dom.inDocument(el);
```
</td>
<td>
```
myNode.inDoc();
```
</td>
</tr>
<tr>
<td>
```
Dom.batch(elementArray,
Dom.addClass, 'highlight');
```
</td>
<td>
```
myNodelist.addClass('highlight');
// OR
myNodelist.each(function (node) {
node.addClass('highlight')
});
// OR
Y.Array.each(myNodelist, function (node) {
node.addClass('highlight');
});
```
</td>
</tr>
<tr>
<td>
```
```
</td>
<td>
```
Y.guid();
```
</td>
</tr>
<tr>
<td>
```
```
</td>
<td>
```
myNode.get('winHeight');
myNode.get('winWidth');
```
</td>
</tr>
<tr>
<td>
```
```
</td>
<td>
```
myNode.get('docHeight');
myNode.get('docWidth');
```
</td>
</tr>
<tr>
<td>
```
```
</td>
<td>
```
myNode.get('viewportRegion');
```
</td>
</tr>
<tr>
<td>
```
Dom.getRegion(el);
```
</td>
<td>
```
myNode.get('region');
```
</td>
</tr>
<tr>
<td>
```
```
</td>
<td>
```
myNode.get('docScrollX');
myNode.get('docScrollY');
```
</td>
</tr>
</tbody>
</table>