Getting Started

Using the Button ARIA Plugin is easy. Simply include the source file(s) for the ARIA plugin after the Button source files as indicated on the Button landing page.

<!-- Source file --> <script type="text/javascript" src="../button/assets/buttonariaplugin.js"></script> <!-- OPTIONAL: Menu and Container ARIA Plugin files (required for creating Buttons of type "menu" and "split") --> <script type="text/javascript" src="../container/assets/containerariaplugin.js"></script> <script type="text/javascript" src="../menu/assets/menuariaplugin.js"></script>

All YUI ARIA Plugins require the user's browser and AT support the WAI-ARIA Roles and States. Currently only Firefox 3 and Internet Explorer 8 have support for ARIA, and are supported by several screen readers for Windows that also offer support for ARIA. For this reason the YUI ARIA Plugins are only enabled by default for these browsers. To enable the ARIA plugin for other browsers, simply the set the usearia attribute to true. For example:

var oButton = new YAHOO.widget.Button({ type: "checkbox", usearia: true, label: "A Checkbox", name: "checkbox-1", value: "1", container: document.body });

The same is true of the ButtonGroup widget:

var oButtonGroup = new YAHOO.widget.ButtonGroup({ name: "radiogroup-1", container: document.body, usearia: true }); oButtonGroup.addButtons([ { label: "Radio 1", value: "1" checked: true }, { label: "Radio 2", value: "2" }, { label: "Radio 3", value: "3" }, { label: "Radio 4", value: "4" } ]);

Plugin Features

More Accessible Radio Buttons and Checkboxes

All Buttons (with the exception of those of type link) created using the Button widget are represented in HTML using the <button> element. While this element suits most applications, it doesn't convey the correct role information for Buttons of type checkbox and radio. For this reason the Button ARIA Plugin sets the ARIA role attribute of each Button to either checkbox and radio, and the ARIA role attribute for the root element of a ButtonGroup to radiogroup. Lastly, for Buttons of type checkbox and radio, the Button ARIA Plugin automatically toggles the aria-checked attribute as the Button's checked attribute changes.

The labelledby and describedby Attributes.

The Button ARIA Plugin adds a labelledby and describedby attribute to the ButtonGroup class, each of which maps back to their respective ARIA property of aria-labelledby and aria-describedby.

var oButtonGroup = new YAHOO.widget.ButtonGroup("buttongroup", { labelledby: "buttongroup-label" });

More Accessible Split Buttons and Menu Buttons

As indicated above, Buttons of type menu and split require the Container and Menu ARIA Plugins. No additional configuration of a Button's Menu is required. Setting the usearia attribute to true for a Button will automatically set the corresponding property on its Menu. Additionally, the aria-haspop attribute will automatically be set to true for each Button's <button> element so that users of AT know that the Button has a corresponding Menu. The Menu's labelledby configuration property will automatically be set to the id of the Button, to further associate the Menu with its corresponding Button for users of AT.

Screen Reader Testing

Two of the leading screen readers for Windows, JAWS and Window-Eyes, support ARIA. Free, trial versions of both are available for download, but require Windows be restarted every 40 minutes. The open-source NVDA Screen Reader is the best option for developers as it is both free and provides excellent support for ARIA.

Configuration for This Example

You can load the necessary JavaScript and CSS for this example from Yahoo's servers. Click here to load the YUI Dependency Configurator with all of this example's dependencies preconfigured.