YUI recommends YUI3.
YUI 2 has been deprecated since 2011. This site acts as an archive for files and documentation.
This documentation is no longer maintained.
(function () {
var Event = YAHOO.util.Event,
Dom = YAHOO.util.Dom,
Lang = YAHOO.lang,
UA = YAHOO.env.ua,
ContextMenu = YAHOO.widget.ContextMenu,
MenuPrototype = YAHOO.widget.Menu.prototype,
fnMenuInitDefaultConfig = MenuPrototype.initDefaultConfig,
// The currently focused MenuItem label, or the MenuItem label that can be focused
// by the user.
m_oCurrentItemLabel,
// Private constants for strings
_ARIA_PREFIX = "aria-",
_HAS_POPUP = "haspopup",
_ROLE = "role",
_PRESENTATION = "presentation",
_MENUITEM = "menuitem",
_HREF = "href",
_SUBMENU = "submenu",
_MENU = "menu",
_MENUBAR = "menubar",
_LABELLED_BY = "labelledby",
_FOCUS = "focus",
_BLUR = "blur",
_ITEM_ADDED = "itemAdded",
_USE_ARIA = "usearia"
_TRIGGER = "trigger";
// Menu ARIA plugin
var setARIARole = function (element, role) {
element.setAttribute(_ROLE, role);
};
var setARIAProperty = function (element, property, value) {
element.setAttribute((_ARIA_PREFIX + property), value);
};
var addHasPopupRole = function (element) {
if (element.nodeType === 1) {
setARIAProperty(element, _HAS_POPUP, true);
}
};
var removeHasPopupRole = function (element) {
if (element.nodeType === 1) {
element.removeAttribute(_ARIA_PREFIX + _HAS_POPUP);
}
};
var onFocus = function (type, args) {
var oEvent = args[0],
oTarget = Event.getTarget(oEvent); // The currently focused element
// Modify value of the tabIndex attribute so that the currently
// focused MenuItem label is in the browser's default tab order.
if (m_oCurrentItemLabel) {
m_oCurrentItemLabel.tabIndex = -1;
}
m_oCurrentItemLabel = oTarget;
m_oCurrentItemLabel.tabIndex = 0;
};
var onBlur = function (type, args) {
var oEvent = args[0],
oTarget = Event.getTarget(oEvent); // The currently focused element
// If the focus has moved to an element on the page that is not a
// part of the Menu, restore the Menu to its original state
// so that the first item is in the browser's default tab index.
m_oCurrentItemLabel.tabIndex = -1;
m_oCurrentItemLabel = Dom.getFirstChild(this.getItem(0).element);
m_oCurrentItemLabel.tabIndex = 0;
};
var onConfigSubmenu = function (type, args) {
var oSubmenu = args[0];
if (oSubmenu) {
addHasPopupRole(Dom.getFirstChild(this.element));
}
};
var addMenuItemRole = function (menuitem) {
var oMenuItemEl = menuitem.element;
// For NVDA: add the role of "presentation" to reach LI and UL
// element to prevent NVDA from announcing the "list" role
// as well as the menu-related roles.
setARIARole(oMenuItemEl.parentNode, _PRESENTATION);
setARIARole(oMenuItemEl, _PRESENTATION);
// Retrieve a reference to the anchor element that serves as the
// label for each MenuItem.
var oMenuItemLabel = Dom.getFirstChild(oMenuItemEl);
// Set the "role" attribute of the label to "menuitem"
setARIARole(oMenuItemLabel, _MENUITEM);
// Remove the label from the browser's default tab order
oMenuItemLabel.tabIndex = -1;
// JAWS & NVDA announce the value of each anchor
// element's "href" attribute when it recieves focus, so remove
// the attribute so that its value isn't announced.
oMenuItemLabel.removeAttribute(_HREF);
// If the MenuItem has a submenu, set the "aria-haspopup"
// attribute to true so that the screen reader can announce
if (menuitem.cfg.getProperty(_SUBMENU)) {
addHasPopupRole(oMenuItemLabel);
}
else {
menuitem.cfg.subscribeToConfigEvent(_SUBMENU, onConfigSubmenu);
}
};
var onItemAdded = function (type, args) {
addMenuItemRole(args[0]);
};
Lang.augmentObject(MenuPrototype, {
configUseARIA: function (type, args) {
var bUseARIA = args[0],
oParent = this.parent,
oElement = this.element,
sMenuRole = (this instanceof YAHOO.widget.MenuBar) ? _MENUBAR : _MENU,
aMenuItems,
nMenuItems,
oMenuItem,
oMenuItemLabel,
sId,
i;
if (bUseARIA) {
// Apply the "role" attribute of "menu" or "menubar" depending on the
// type of the Menu control being rendered.
setARIARole(oElement, sMenuRole);
// Use the "aria-labelledby" attribute to label each submenu. This
// will provide the user with the name of the submenu the first time
// one of its items receives focus.
if (oParent) {
sId = Dom.generateId(Dom.getFirstChild(oParent.element));
setARIAProperty(oElement, _LABELLED_BY, sId);
}
// Apply the appropriate "role" and "aria-[state]" attributes to the
// label of each MenuItem instance.
aMenuItems = this.getItems();
nMenuItems = aMenuItems.length;
if (nMenuItems > 0) {
i = nMenuItems - 1;
do {
oMenuItem = aMenuItems[i];
addMenuItemRole(oMenuItem);
i = i - 1;
}
while ((i > -1));
// Set the "tabindex" of the first MenuItem's label to 0 so the user
// can easily tab into and out of the control.
if (this.getRoot() === this) {
m_oCurrentItemLabel = Dom.getFirstChild(this.getItem(0).element);
m_oCurrentItemLabel.tabIndex = 0;
}
}
if (this === this.getRoot()) {
this.subscribe(_FOCUS, onFocus);
this.subscribe(_BLUR, onBlur);
}
this.subscribe(_ITEM_ADDED, onItemAdded);
}
},
initDefaultConfig: function () {
fnMenuInitDefaultConfig.call(this);
this.cfg.addProperty(
_USE_ARIA,
{
handler: this.configUseARIA,
value: (UA.gecko && UA.gecko >= 1.9) || (UA.ie && UA.ie >= 8),
validator: Lang.isBoolean
}
);
}
}, "initDefaultConfig", "configUseARIA");
// ContextMenu ARIA plugin
var m_oTriggers = {};
var toggleARIAForTrigger = function () {
var sMenuId = this.element.id,
oTrigger = this.cfg.getProperty(_TRIGGER),
oCurrentTrigger = m_oTriggers[sMenuId],
oElement;
if (oCurrentTrigger) {
if (Lang.isString(oCurrentTrigger)) { // String id
oElement = Dom.get(oCurrentTrigger);
if (oElement) {
removeHasPopupRole(oElement);
}
}
else if (oCurrentTrigger.nodeType === 1) { // Element reference
removeHasPopupRole(oCurrentTrigger);
}
else if (oCurrentTrigger.length) { // NodeList or Array
Dom.batch(oCurrentTrigger, removeHasPopupRole);
}
}
if (oTrigger) {
if (Lang.isString(oTrigger)) { // String id
oElement = Dom.get(oTrigger);
if (oElement) {
addHasPopupRole(oElement);
}
}
else if (oTrigger.nodeType === 1) { // Element reference
addHasPopupRole(oTrigger);
}
else if (oTrigger.length) { // NodeList or Array
Dom.batch(oTrigger, addHasPopupRole);
}
m_oTriggers[sMenuId] = oTrigger;
}
};
ContextMenu.prototype.configUseARIA = function (type, args) {
ContextMenu.superclass.configUseARIA.apply(this, arguments);
toggleARIAForTrigger.call(this);
this.cfg.subscribeToConfigEvent(_TRIGGER, toggleARIAForTrigger);
};
}());