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define("dijit/a11y", [
"dojo/_base/array", // array.forEach array.map
"dojo/_base/config", // defaultDuration
"dojo/_base/declare", // declare
"dojo/dom", // dom.byId
"dojo/dom-attr", // domAttr.attr domAttr.has
"dojo/dom-style", // style.style
"dojo/_base/sniff", // has("ie")
"./_base/manager", // manager._isElementShown
"." // for exporting methods to dijit namespace
], function(array, config, declare, dom, domAttr, domStyle, has, manager, dijit){
// module:
// dijit/a11y
// summary:
// Accessibility utility functions (keyboard, tab stops, etc.)
var shown = (dijit._isElementShown = function(/*Element*/ elem){
var s = domStyle.get(elem);
return (s.visibility != "hidden")
&& (s.visibility != "collapsed")
&& (s.display != "none")
&& (domAttr.get(elem, "type") != "hidden");
});
dijit.hasDefaultTabStop = function(/*Element*/ elem){
// summary:
// Tests if element is tab-navigable even without an explicit tabIndex setting
// No explicit tabIndex setting, need to investigate node type
switch(elem.nodeName.toLowerCase()){
case "a":
// An <a> w/out a tabindex is only navigable if it has an href
return domAttr.has(elem, "href");
case "area":
case "button":
case "input":
case "object":
case "select":
case "textarea":
// These are navigable by default
return true;
case "iframe":
// If it's an editor <iframe> then it's tab navigable.
var body;
try{
// non-IE
var contentDocument = elem.contentDocument;
if("designMode" in contentDocument && contentDocument.designMode == "on"){
return true;
}
body = contentDocument.body;
}catch(e1){
// contentWindow.document isn't accessible within IE7/8
// if the iframe.src points to a foreign url and this
// page contains an element, that could get focus
try{
body = elem.contentWindow.document.body;
}catch(e2){
return false;
}
}
return body && (body.contentEditable == 'true' ||
(body.firstChild && body.firstChild.contentEditable == 'true'));
default:
return elem.contentEditable == 'true';
}
};
var isTabNavigable = (dijit.isTabNavigable = function(/*Element*/ elem){
// summary:
// Tests if an element is tab-navigable
// TODO: convert (and rename method) to return effective tabIndex; will save time in _getTabNavigable()
if(domAttr.get(elem, "disabled")){
return false;
}else if(domAttr.has(elem, "tabIndex")){
// Explicit tab index setting
return domAttr.get(elem, "tabIndex") >= 0; // boolean
}else{
// No explicit tabIndex setting, so depends on node type
return dijit.hasDefaultTabStop(elem);
}
});
dijit._getTabNavigable = function(/*DOMNode*/ root){
// summary:
// Finds descendants of the specified root node.
//
// description:
// Finds the following descendants of the specified root node:
// * the first tab-navigable element in document order
// without a tabIndex or with tabIndex="0"
// * the last tab-navigable element in document order
// without a tabIndex or with tabIndex="0"
// * the first element in document order with the lowest
// positive tabIndex value
// * the last element in document order with the highest
// positive tabIndex value
var first, last, lowest, lowestTabindex, highest, highestTabindex, radioSelected = {};
function radioName(node){
// If this element is part of a radio button group, return the name for that group.
return node && node.tagName.toLowerCase() == "input" &&
node.type && node.type.toLowerCase() == "radio" &&
node.name && node.name.toLowerCase();
}
var walkTree = function(/*DOMNode*/parent){
for(var child = parent.firstChild; child; child = child.nextSibling){
// Skip text elements, hidden elements, and also non-HTML elements (those in custom namespaces) in IE,
// since show() invokes getAttribute("type"), which crash on VML nodes in IE.
if(child.nodeType != 1 || (has("ie") && child.scopeName !== "HTML") || !shown(child)){
continue;
}
if(isTabNavigable(child)){
var tabindex = domAttr.get(child, "tabIndex");
if(!domAttr.has(child, "tabIndex") || tabindex == 0){
if(!first){
first = child;
}
last = child;
}else if(tabindex > 0){
if(!lowest || tabindex < lowestTabindex){
lowestTabindex = tabindex;
lowest = child;
}
if(!highest || tabindex >= highestTabindex){
highestTabindex = tabindex;
highest = child;
}
}
var rn = radioName(child);
if(domAttr.get(child, "checked") && rn){
radioSelected[rn] = child;
}
}
if(child.nodeName.toUpperCase() != 'SELECT'){
walkTree(child);
}
}
};
if(shown(root)){
walkTree(root);
}
function rs(node){
// substitute checked radio button for unchecked one, if there is a checked one with the same name.
return radioSelected[radioName(node)] || node;
}
return { first: rs(first), last: rs(last), lowest: rs(lowest), highest: rs(highest) };
};
dijit.getFirstInTabbingOrder = function(/*String|DOMNode*/ root){
// summary:
// Finds the descendant of the specified root node
// that is first in the tabbing order
var elems = dijit._getTabNavigable(dom.byId(root));
return elems.lowest ? elems.lowest : elems.first; // DomNode
};
dijit.getLastInTabbingOrder = function(/*String|DOMNode*/ root){
// summary:
// Finds the descendant of the specified root node
// that is last in the tabbing order
var elems = dijit._getTabNavigable(dom.byId(root));
return elems.last ? elems.last : elems.highest; // DomNode
};
return {
hasDefaultTabStop: dijit.hasDefaultTabStop,
isTabNavigable: dijit.isTabNavigable,
_getTabNavigable: dijit._getTabNavigable,
getFirstInTabbingOrder: dijit.getFirstInTabbingOrder,
getLastInTabbingOrder: dijit.getLastInTabbingOrder
};
});
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