- Author:
- David Nickerson <nickerso@users.sourceforge.net>
- Date:
- 2009-07-16 02:00:03+12:00
- Desc:
- the starting point for the HH tutorial example
- Permanent Source URI:
- https://models.fieldml.org/workspace/a1/rawfile/f6a8f90307388eb4b040ee3566b84d88b59247f7/dojo-presentation/js/dojo/dijit/_base/wai.js
dojo.provide("dijit._base.wai");
dijit.wai = {
onload: function(){
// summary:
// Detects if we are in high-contrast mode or not
// This must be a named function and not an anonymous
// function, so that the widget parsing code can make sure it
// registers its onload function after this function.
// DO NOT USE "this" within this function.
// create div for testing if high contrast mode is on or images are turned off
var div = dojo.doc.createElement("div");
div.id = "a11yTestNode";
div.style.cssText = 'border: 1px solid;'
+ 'border-color:red green;'
+ 'position: absolute;'
+ 'height: 5px;'
+ 'top: -999px;'
+ 'background-image: url("' + (dojo.config.blankGif || dojo.moduleUrl("dojo", "resources/blank.gif")) + '");';
dojo.body().appendChild(div);
// test it
var cs = dojo.getComputedStyle(div);
if(cs){
var bkImg = cs.backgroundImage;
var needsA11y = (cs.borderTopColor==cs.borderRightColor) || (bkImg != null && (bkImg == "none" || bkImg == "url(invalid-url:)" ));
dojo[needsA11y ? "addClass" : "removeClass"](dojo.body(), "dijit_a11y");
if(dojo.isIE){
div.outerHTML = ""; // prevent mixed-content warning, see http://support.microsoft.com/kb/925014
}else{
dojo.body().removeChild(div);
}
}
}
};
// Test if computer is in high contrast mode.
// Make sure the a11y test runs first, before widgets are instantiated.
if(dojo.isIE || dojo.isMoz){ // NOTE: checking in Safari messes things up
dojo._loaders.unshift(dijit.wai.onload);
}
dojo.mixin(dijit,
{
_XhtmlRoles: /banner|contentinfo|definition|main|navigation|search|note|secondary|seealso/,
hasWaiRole: function(/*Element*/ elem, /*String*/ role){
// summary: Determines if an element has a particular non-XHTML role.
// returns: true if elem has the specific non-XHTML role attribute and false if not.
// for backwards compatibility if role parameter not provided,
// returns true if has non XHTML role
var waiRole = this.getWaiRole(elem);
if (role){
return (waiRole.indexOf(role) > -1);
}else{
return (waiRole.length >0);
}
},
getWaiRole: function(/*Element*/ elem){
// summary: Gets the non-XHTML role for an element (which should be a wai role).
// returns:
// The non-XHTML role of elem or an empty string if elem
// does not have a role.
return dojo.trim((dojo.attr(elem, "role") || "").replace(this._XhtmlRoles,"").replace("wairole:",""));
},
setWaiRole: function(/*Element*/ elem, /*String*/ role){
// summary: Sets the role on an element.
// description:
// in other than FF2 replace existing role attribute with new role
// FF3 supports XHTML and ARIA roles so
// If elem already has an XHTML role, append this role to XHTML role
// and remove other ARIA roles
// On Firefox 2 and below, "wairole:" is
// prepended to the provided role value.
var curRole = (theRole = dojo.attr(elem, "role")) ? theRole : "";
if (dojo.isFF<3 || !this._XhtmlRoles.test(curRole)){
dojo.attr(elem, "role", dojo.isFF<3 ? "wairole:" + role : role);
}else{
if((" "+ curRole +" ").indexOf(" " + role + " ") < 0){
var clearXhtml = dojo.trim(curRole.replace(this._XhtmlRoles, ""));
var cleanRole = dojo.trim(curRole.replace(clearXhtml, ""));
dojo.attr(elem, "role", cleanRole + (cleanRole ? ' ' : '') + role);
}
}
},
removeWaiRole: function(/*Element*/ elem, /*String*/ role){
// summary: Removes the specified non-XHTML role from an element.
// removes role attribute if no specific role provided (for backwards compat.)
var roleValue = dojo.attr(elem, "role");
if (!roleValue){ return; }
if(role){
var searchRole = dojo.isFF < 3 ? "wairole:" + role : role;
var t = dojo.trim((" " + roleValue + " ").replace(" " + searchRole + " ", " "));
dojo.attr(elem, "role", t);
}else{
elem.removeAttribute("role");
}
},
hasWaiState: function(/*Element*/ elem, /*String*/ state){
// summary: Determines if an element has a given state.
// description:
// On Firefox 2 and below, we check for an attribute in namespace
// "http://www.w3.org/2005/07/aaa" with a name of the given state.
// On all other browsers, we check for an attribute
// called "aria-"+state.
// returns:
// true if elem has a value for the given state and
// false if it does not.
if(dojo.isFF < 3){
return elem.hasAttributeNS("http://www.w3.org/2005/07/aaa", state);
}else{
return elem.hasAttribute ? elem.hasAttribute("aria-"+state) : !!elem.getAttribute("aria-"+state);
}
},
getWaiState: function(/*Element*/ elem, /*String*/ state){
// summary: Gets the value of a state on an element.
// description:
// On Firefox 2 and below, we check for an attribute in namespace
// "http://www.w3.org/2005/07/aaa" with a name of the given state.
// On all other browsers, we check for an attribute called
// "aria-"+state.
// returns:
// The value of the requested state on elem
// or an empty string if elem has no value for state.
if(dojo.isFF < 3){
return elem.getAttributeNS("http://www.w3.org/2005/07/aaa", state);
}else{
var value = elem.getAttribute("aria-"+state);
return value ? value : "";
}
},
setWaiState: function(/*Element*/ elem, /*String*/ state, /*String*/ value){
// summary: Sets a state on an element.
// description:
// On Firefox 2 and below, we set an attribute in namespace
// "http://www.w3.org/2005/07/aaa" with a name of the given state.
// On all other browsers, we set an attribute called
// "aria-"+state.
if(dojo.isFF < 3){
elem.setAttributeNS("http://www.w3.org/2005/07/aaa",
"aaa:"+state, value);
}else{
elem.setAttribute("aria-"+state, value);
}
},
removeWaiState: function(/*Element*/ elem, /*String*/ state){
// summary: Removes a state from an element.
// description:
// On Firefox 2 and below, we remove the attribute in namespace
// "http://www.w3.org/2005/07/aaa" with a name of the given state.
// On all other browsers, we remove the attribute called
// "aria-"+state.
if(dojo.isFF < 3){
elem.removeAttributeNS("http://www.w3.org/2005/07/aaa", state);
}else{
elem.removeAttribute("aria-"+state);
}
}
});
