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:
See User Agent Support Notes for FLASH11. Also see Flash Technology Notes.
The objective of this technique is to a provide longer, more detailed textual information for an image than would be suitable for the image's accessible name. An accessible button is provided adjacent to the image that displays a new panel containing the image's long description text.
In this example, an image containing statistical data is shown. The image is provided a short textual alternative ("Graph of percentage of total U.S. noninsitutionalized population age 16-64 declaring one or more disabilities"). Below the image, the user can click a button that will overlay a long textual description of the statistical information itself. When the button is clicked, the following actions are taken:
The MovieClip containing the long text description is made visible, and its AccessibilityProperties.silent property is set to false to make it visible to assistive technology. Its contents are placed in the tab order.
The original image and button are temporarily hidden from assistive technology and the tab order.
The image and descriptive text were taken from a previously published HTML example for long image descriptions on WebAIM.org
The results for this technique are shown in the working version of Making a hidden description visible on request. The source of Making a hidden description visible on request is available.
Example Code:
import flash.accessibility. *;
import fl.accessibility.ButtonAccImpl;
import flash.system.Capabilities;
ButtonAccImpl.enableAccessibility();
//set accessibility properties
graph_mc.accessibilityProperties = new AccessibilityProperties();
graph_mc.accessibilityProperties.name = "Graph of percentage of total U.S. \
noninsitutionalized population age 16-64 declaring one or more disabilities";
longDescBtn.accessibilityProperties = new AccessibilityProperties();
longDesc_mc.accessibilityProperties = new AccessibilityProperties();
longDesc_mc.accessibilityProperties.forceSimple = false;
hideLongDesc();
//set click handlers for button
longDescBtn.addEventListener("click", function () {
showLongDesc()
});
longDesc_mc.longDescCloseBtn.addEventListener("click", function () {
hideLongDesc()
});
function showLongDesc() {
// hide the original content from screen readers
graph_mc.accessibilityProperties.silent = true;
graph_mc.tabEnabled = false;
graph_mc.alpha = 0.2;
longDescBtn.enabled = false;
longDescBtn.accessibilityProperties.silent = true;
longDesc_mc.accessibilityProperties.silent = false;
// make the long description panel visible, both visually and to screen readers
longDesc_mc.visible = true;
longDesc_mc.tabEnabled = true;
longDesc_mc.longDescTitle.stage.focus = longDesc_mc.longDescTitle;
if (Capabilities.hasAccessibility)
Accessibility.updateProperties();
}
function hideLongDesc() {
//do the opposite to what showLongDesc does
graph_mc.accessibilityProperties.silent = false;
graph_mc.tabEnabled = true;
graph_mc.alpha = 1;
longDescBtn.enabled = true;
longDescBtn.accessibilityProperties.silent = false;
longDesc_mc.visible = false;
longDesc_mc.accessibilityProperties.silent = true;
longDesc_mc.tabEnabled = false;
longDescBtn.stage.focus = longDescBtn;
if (Capabilities.hasAccessibility)
Accessibility.updateProperties();
}
When a Flash movie contains images that require long descriptions, confirm that a longer description is made available through a separate button.
The above 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.