<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><em>The `Y.get()`, `node.query()`, and
        `node.queryAll()` methods have been removed. Use `Y.one()`,
        `node.one()`, and `node.all()`.</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").setHTML("<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_setHTML">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.setHTML(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) {
    e.preventDefault();
    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 () {
        completedTasklist.appendChild(this);
    });
});
```

<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('bar');
}

// adds class "syntax-highlight" to all <pre> descendants of #demo
node.all('pre').addClass('syntax-highlight');
```

<p>
    Like `Y.one()` and `Y.all()`, `Node` instances have `one()` and `all()`
    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
    in large pages as well, because `Y.one()` and `Y.all()` always query from
    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.getPreviousSibling(el);
            Dom.getPreviousSiblingBy(someFilterFunction);
            ```
        </td>
        <td>
            ```
            myNode.next();
            myNode.next('selectorString');
            myNode.previous();
            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>
            ```
            Dom.generateId();
            ```
        </td>
        <td>
            ```
            Y.guid();
            ```
        </td>
    </tr>
    <tr>
        <td>
            ```
            Dom.getViewportHeight();
            Dom.getViewportWidth();
            ```
        </td>
        <td>
            ```
            myNode.get('winHeight');
            myNode.get('winWidth');
            ```
        </td>
    </tr>
    <tr>
        <td>
            ```
            Dom.getDocumentHeight();
            Dom.getDocumentWidth();
            ```
        </td>
        <td>
            ```
            myNode.get('docHeight');
            myNode.get('docWidth');
            ```
        </td>
    </tr>
    <tr>
        <td>
            ```
            Dom.getClientRegion();
            ```
        </td>
        <td>
            ```
            myNode.get('viewportRegion');
            ```
        </td>
    </tr>
    <tr>
        <td>
            ```
            Dom.getRegion(el);
            ```
        </td>
        <td>
            ```
            myNode.get('region');
            ```
        </td>
    </tr>
    <tr>
        <td>
            ```
            Dom.getDocumentScrollLeft();
            Dom.getDocumentScrollTop();
            ```
        </td>
        <td>
            ```
            myNode.get('docScrollX');
            myNode.get('docScrollY');
            ```
        </td>
    </tr>
</tbody>
</table>
