This document is a draft, and is designed to show changes from a previous version. It is presently showing added text,changed text,deleted text,[start]/[end] markers,and Issue Numbers.
Changes are displayed as follows:
area elements of image maps
HTML 4, XHTML 1.0 and XHTML 1.1 Documents that contain area elements.
This technique relates to:
The HTML 4.01 specification explains that the text of the alt attribute is to be displayed when the element can not be rendered normally. User Agents will display the alt attribute text when images are not displayed. [begin add]However, currently, visual User Agents
do not display the alt attribute text for area elements of image maps
when accessed by keyboard or when images are not displayed, and may clip
the area elements if the intrinsic size of the image is not used. In
addition, the display of alt attribute text in response to mouse-hover
does not display in the font size or color combination set in the User
Agent.
[end add]
The title attribute is meant to provide additional information. [begin add]However, current implementation in User Agents is access to either the
title or alt attribute, but not both. [end add]User Agents generally will display the title attribute text when the mouse is placed over the element containing the title attribute. For example, Internet Explorer will display the alt text on mouse-over if there is no title text, Firefox and Opera only display the title text on mouse-over and do not use the alt attribute text for this purpose. [begin change]Thus, to ensure the alt attribute text is visible on mouse-over, the same
text should be used on the title attribute.[end change]
Therefore, when using image maps, successful implementation of this technique would require either:
[end add]Ensuring the area element alt attribute value is displayed in response to attaining focus (including keyboard focus), and that this applies both to situations where images are loaded and not loaded. OR
A redundant mechanism serving the same purpose as the area elements is present in the Web Page.
The objective of this technique is to provide text alternatives that serve the same purpose as the selectable regions of an image map. An image map is an image divided into selectable regions defined by area elements. Each area is a link to another Web page or another part of the current Web page. The alt attribute of each area element serves the same purpose as the selectable area of the image.
This example uses the alt attribute of the area element to provide text that describes the purpose of the image map areas.
<img src="welcome.gif" usemap="#map1"
alt="Areas in the library" />
<map id="map1" name="map1">
<area shape="rect" coords="0,0,30,30"
href="reference.html" alt="Reference" />
<area shape="rect" coords="34,34,100,100"
href="media.html" alt="Audio visual lab" />
</map>
Resources are for information purposes only, no endorsement implied.
For each area element in an image map:
Check that the area element has an alt attribute.
Check that the text alternative specified by the alt attribute serves the same purpose as the part of image map image referenced by the area element of the imagemap.
The above checks are true.