Node

<script src="http://yui.yahooapis.com/3.4.0/build/yui/yui-min.js"></script>

// Create a new YUI instance and populate it with the required modules.
YUI().use('node', function (Y) {
    // Node is available and ready for use. Add implementation
    // code here.
});

Using Node

Getting a Node

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.

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 selector query. If a selector query is used, the first matching element is used.

Note: CSS3 selector support is not included by default with Node, you will need to include the "selector-css3" module for CSS3 support.

This example demonstrates two ways to get a node instance.

var node1 = Y.one('#main');
var node2 = Y.one(document.body);

Accessing Node Properties

Properties of the underlying DOM node are accessed via the Y.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 Y.Node instances instead.

This is an example of getting and setting various properties.

var node = Y.one('#foo');
var parent = node.get('parentNode'); // Node instance

var html = 'I am "' + node.get('id') + '".';
html += 'My parent is "' + parent.get('id') + '"';

node.set('innerHTML', html);

DOM Events

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 Y.Node instances.

Y.one('#demo').on('click', function(e) {
    e.preventDefault();
    alert('event: ' + e.type + ' target: ' + e.target.get('tagName')); 
});

DOM Methods

The Y.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 Y.Node instances.

var node = Y.one('#demo');
var node2 = node.appendChild(Y.one('#foo p'));
node2.addClass('bar');

Using NodeList

The Y.NodeList provides a node-like interface for manipulating multiple nodes through a single interface. The NodeList API is a pared-down version of the Node API, allowing for batching of common tasks.

The Y.all method is the simplest way to get a NodeList.

Y.all('#demo li').addClass('bar');

The Y.Node api returns NodeList instances when the DOM would normally return a collection of elements.

Y.one('#demo').get('children').addClass('bar');

Node Queries

Selector queries are a powerful way to test and manipulate nodes. All Y.Node instances support one, all, and test.

var node = Y.one('#demo');

var node2 = node.one('p');
if (node2) { // might be null
    node2.addClass('bar'); // adds "bar" to the first paragraph descendant of #demo
}

node.all('p').addClass('bar'); // adds "bar" to all paragraph descendants of #demo

if (node.test('.foo.bar')) { // "if node has both foo and bar classNames"
    node.removeClass('bar');
}

For more information on selector queries, see the following W3C specifications:

• CSS Level 3 Selectors
• Selectors API

Note: CSS3 selector support is not included by default with Node, you will need to include the "selector-css3" module for CSS3 support.

ARIA Support

The Node interface has support for ARIA. When used with Node's built-in support for CSS selector queries, it is easy to both apply and manage a Node's roles, states and properties.

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.

Apply any of the ARIA Roles, States and Properties via the set method. For example, to apply the role of toolbar to a <div> with an id of "toolbar":

var node = Y.one('#toolbar').set('role', 'toolbar');

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 menubar to the root DOM element representing the menubar, and the role of menu to the root DOM element representing each submenu. Additionally, as each submenu is hidden by default, the aria-hidden 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:

var node = Y.one('#rootmenu').set('role', 'menubar'),
    nodes = node.all('.menu');
    
nodes.setAttrs({ role: 'menu', 'aria-hidden': true });

Migration Table

The following table is included to help users migrating from YUI 2. Most of the functionality from YAHOO.util.Dom is available via Node.

Note In the snippets below, myNode is an instance of Node. Methods that normally would return DOM nodes now return Node instances.

2.x (via YAHOO.util.Dom)	3.0
addClass	myNode.addClass
batch	NodeList[methodName], NodeList.each, or Y.each
generateId	Y.guid
get	Y.one Note strings are now treated as selectors (e.g. "Y.one('#foo')" vs. "YAHOO.util.Dom.get('foo')")
getAncestorBy	myNode.ancestor
getAncestorByClassName	myNode.ancestor
getAncestorByTagName	myNode.ancestor
getChildren	myNode.get('children')
getChildrenBy	myNode.all
getClientRegion	myNode.get('viewportRegion')
getDocumentHeight	myNode.get('docHeight')
getDocumentScrollLeft	myNode.get('docScrollX')
getDocumentScrollTop	myNode.get('docScrollY')
getDocumentWidth	myNode.get('docWidth')
getElementsBy	myNode.all
getElementsByClassName	myNode.all
getFirstChild	myNode.one
getFirstChildBy	myNode.one
getLastChild	myNode.one
getLastChildBy	myNode.one
getNextSibling	myNode.next
getNextSiblingBy	myNode.next
getPreviousSibling	myNode.previous
getPreviousSiblingBy	myNode.previous
getRegion	myNode.get('region')
getStyle	myNode.getStyle
getViewportHeight	myNode.get('winHeight')
getViewportWidth	myNode.get('winWidth')
getX	myNode.getXY
getY	myNode.getXY
getXY	myNode.getXY
hasClass	myNode.hasClass
inDocument	myNode.inDoc
insertAfter	myNode.insert
insertBefore	myNode.insert
isAncestor	myNode.contains (Note myNode.contains(myNode) === true)
removeClass	myNode.removeClass
replaceClass	myNode.replaceClass
setStyle	myNode.setStyle
setX	myNode.setXY
setY	myNode.setXY
setXY	myNode.setXY