See Understanding Techniques for WCAG Success Criteria for important information about the usage of these informative techniques and how they relate to the normative WCAG 2.0 success criteria. The Applicability section explains the scope of the technique, and the presence of techniques for a specific technology does not imply that the technology can be used in all situations to create content that meets WCAG 2.0.
Adobe Flash Professional version MX and higher
Adobe Flex
This technique relates to:
Note: This technique must be combined with other techniques to meet SC 1.4.8. See Understanding SC 1.4.8 for details.
See User Agent Support Notes for FLASH33. Also see Flash Technology Notes.
The objective of this technique is to specify the width and/or height
of an embedded Flash object using relative units such as em
values.
The size of the Flash object is allowed to expand to fill the size
of its container (a parent element) by setting the movie width and
height to 100%. The container's width and height is set with relative
units. This will allow user agents that support text resizing to resize
the Flash object in line with changes in text size settings. When the
Flash object's dimensions are adjusted its contents will be scaled,
making it easier to read for low vision users.
Note: This technique is not necessary to support users who use zoom functionality in their browsers.
In this example, a Flash object is loaded into an HTML document using SWFObject's
dynamic publishing method. The Flash object's container element
is given a class name of "flashPlaceHolder". This class
name is then targeted using CSS to set its width and height using
relative em values. When the user increases or decreases the browser's
text size, the Flash object will scale accordingly. To ensure that
the object does not become too small when text size is decreased,
the min-width
and min-height
properties are set to the default dimensions.
Example Code:
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta content="text/html; charset=UTF-8" http-equiv="Content-Type"/>
<title>Flash Resize example</title>
<script src="swfobject/swfobject.js" type="text/javascript"/>
<script type="text/javascript">
swfobject.embedSWF("scale_movie_dimensions_on_text_resize_as3.swf",
"flashPlaceHolder", "100%", "100%", "8")
</script>
<style type="text/css">
#flashPlaceHolder {
width: 20em;
height: 15em;
min-width: 320px;
min-height: 240px;
}
</style>
</head>
<body id="header">
<h1>Flash Resize Demonstration</h1>
<p>When the browser's text size is changed, the Flash movie will be
resized accordingly.</p>
<p id="flashPlaceHolder">Flash needs to be installed for this
example to work</p>
</body>
</html>
The result of this technique can be viewed in the working version of Scaling text while keeping a minimum size. The source of Scaling text while keeping a minimum size is available.
Open a web page containing an embedded flash object
View the HTML to confirm that the width and height dimensions for the object containing the Flash object are specified using relative units such as em or percent (%).
Check #2 is true.
If this is a sufficient technique for a success criterion, failing this test procedure does not necessarily mean that the success criterion has not been satisfied in some other way, only that this technique has not been successfully implemented and can not be used to claim conformance.