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Screen readers are software designed to navigate through a website and read the web content aloud. Visually impaired users often rely on this technology. You can create Flash content designed for use with screen readers on only Windows platforms. Those viewing your Flash content must have Flash Player 6 or later, and Internet Explorer on Windows 98 or later.
JAWS, from Freedom Scientific, is one example of screen reader software. You can access the JAWS page of the Freedom Scientific website at www.hj.com/fs_products/software_jaws.asp. Another commonly used screen reader program is Window-Eyes, from GW Micro. To access the latest information on Window-Eyes, visit the GW Micro website at www.gwmicro.com. To enable a screen reader to read nontextual objects in your application, such as vector art and animations, you can use the Accessibility panel to associate a name and description with the object, which the screen reader reads aloud.
Screen readers help users understand what is contained in a web page or Flash document. Based on the keyboard shortcuts you define, you can allow users to navigate through your document using the screen reader with ease. See Creating a keyboard shortcut.
To expose graphic objects, you can provide a description using the Accessibility panel or ActionScript. See Using Flash to enter accessibility information for screen readers.
Because different screen reader applications use varying methods to translate information into speech, your content will vary in how it's presented to each user. As you design accessible applications, keep in mind that you have no control over how a screen reader will behave. You can only mark up the content in your Flash applications in such a way as to expose the text and ensure screen reader users can activate the controls. You only have control over the content, not the screen readers. This means that you can decide which objects in the movie are exposed to screen readers, provide descriptions for them, and decide the order in which they are exposed to screen readers. However, you cannot force screen readers to read specific text at specific times or control the manner in which that content is read. It is very important, therefore, to test your applications with a variety of screen readers to ensure that they perform as you expect. See Testing accessible content.
Flash Player is optimized for Microsoft Active Accessibility (MSAA) which provides a highly descriptive and standardized way for applications and screen readers to communicate. MSAA is available on Windows operating systems only. For more information on Microsoft Accessibility Technology, visit the Microsoft Accessibility website at www.microsoft.com/enable/default.aspx.
The Windows ActiveX (Internet Explorer plug-in) version of Flash Player 6 supports MSAA, but the Windows Netscape and Windows stand-alone players do not.
Caution: MSAA is currently not supported in the opaque windowless and transparent windowless modes. (These modes are options in the HTML Publish Settings panel, available for use with the Windows version of Internet Explorer 4.0 or later, with the Flash ActiveX control.) If you need your Flash content to be accessible to screen readers, avoid using these modes.
Flash Player makes information about the following types of accessibility objects available to screen readers using MSAA. To understand how to enter accessible information for each object, see Using Flash to enter accessibility information for screen readers.
Dynamic or static text The principal property of a text object is its name. To comply with MSAA convention, the name is equal to the contents of the text string. A text object may also have an associated description string. Flash uses the static or dynamic text immediately above or to the left of an input text field as a label for that field.
Note: Any text that is a label is not passed to a screen reader. Instead, the content of that text is used as the name of the object that it labels. Labels are never assigned to buttons or text fields that have author-supplied names.
Input text fields An input text object has a value, an optional name, a description string, and a keyboard shortcut string. Like dynamic text, an input text object's name may come from a text object that is above or to the left of it.
Buttons A button object has a state (pressed or not pressed), supports a programmatic default action that causes the button to depress momentarily, and may optionally have a name, a description string, and a keyboard shortcut string. As with text input fields, for buttons, Flash uses any text entirely inside a button as a label for that button.
Note: For accessibility purposes, movie clips used as buttons with button event handlers such as onPress, are considered buttons, not movie clips, by Flash Player.
Components Flash UI components provide special accessibility implementation. For more information, see Using accessible components and Creating accessibility with ActionScript.
Movie clips Movie clips are exposed to screen readers as graphic objects when they do not contain any other accessible objects, or when the Accessibility panel is used to provide a name or a description for a movie clip. When a movie clip contains other accessibly objects, the clip itself is ignored, and the objects inside it are made available to screen readers.
Note: All Flash Video objects are treated as simple movie clips.
Flash Player provides some basic accessibility support for all Flash documents, whether or not they are designed using the accessibility features found in the Flash authoring tool. This generic support for documents that do not use any accessibility features includes the following:
Dynamic or static text Text is transferred to the screen reader program as a name, but with no description.
Input text Text is transferred to the screen reader. No names are transferred, except where labeling relationships are found, and no descriptions or keyboard shortcut strings are transferred.
Buttons The state of the button is transferred to the screen reader. No names are transferred, except where labeling relationships are found, and no descriptions or keyboard shortcut strings are transferred.
Documents The document state is transferred to the screen reader, but with no name or description.
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