This document describes the implementation status of checkpoints defined in
"Implementation report for User
Agent Accessibility Guidelines 1.0". It is meant to demonstrate that the
requirements specified in the guidelines can be implemented in existing and
future user agents.
There is no implied or presumed endorsement of one type of implementation or
another type of implementation by reference in this document. Inclusion serves
only as an example to developers of the viability of satisfying the
requirements of a checkpoint.
This section describes the status of this document at the time of its
publication. Other documents may supersede this document. The latest status of
this document series is maintained at the W3C.
This is an incomplete version of "Implementation report for
User Agent Accessibility Guidelines 1.0", which the User Agent Accessibility
Guidelines Working Group plans to update prior to advancement of Implementation
report for User Agent Accessibility Guidelines 1.0 on the W3C Recommendation
track. This document was prepared for the Working Group's face-to-face meeting
in Washington, D.C. in November 2000. The information in this document has not
been verified and may be incorrect. This document is support
material for "User Agent Accessibility Guidelines 1.0" [UAAG10] and is
not meant to become a W3C Recommendation. The User Agent Accessibility
Guidelines Working Group (UAWG) expects to update it
periodically with new techniques and information about implementations that
satisfy the guidelines.
This is a W3C Working Draft for review by W3C Members and other interested
parties. It is a draft document and may be updated, replaced or obsoleted by
other documents at any time. It is inappropriate to use W3C Working Drafts as
reference material or to cite them as other than "work in progress". This is
work in progress and does not imply endorsement by, or the consensus of, either
W3C or participants in the User Agent Accessibility Guidelines Working Group
(UAWG).
Please send comments about this document to the public mailing list w3c-wai-ua@w3.org; public archives are
available.
This document is part of a series of accessibility documents published by
the Web Accessibility Initiative (WAI) of the World Wide Web
Consortium (W3C). WAI
Accessibility Guidelines are produced as part of the WAI Technical Activity. The
goals of the User Agent Accessibility
Guidelines Working Group are described in the charter.
A list of current W3C Recommendations and
other technical documents can be found at the W3C Web site.
The implementation examples indicate that a checkpoint has already been
fully or practically implemented by some type of user agent. Each checkpoint
links to information about existing and proposed techniques for satisfying the
checkpoint in "Techniques for User Agent Accessibility Guidelines 1.0"
[UAAG10-TECHS].
Note: Where "no information is available", it may be that
there are not implementations today, that the Working Group is not aware of
any, or that the authors have not yet added the information to this
document.
Most users will be able to verify that most checkpoints have been satisfied.
Those checkpoints that may be difficult to verify without vendor documentation
or support are noted.
Detailed knowledge of the user agent functionality and the operating system
APIs and resources used to implement a feature is typically needed to test
these checkpoints. People other than developers may be able to verify
conformance through interaction with the user interface and compatibility
testing with assistive technology. But in these cases the person may not have
knowledge of all the functionalities of the user agent or be able to test with
all assistive technologies. In the case of assistive technologies it may not be
clear if the detected problems reside in the user agent using appropriate
interfaces to export information or the assistive technology not taking
advantage of information that the user agent is making available.
Checkpoints for communication with other software:
-
1.1 Ensure that every functionality available through the user
interface is also available through every input API that is implemented by the
user agent. This checkpoint does not require developers to reimplement the
input methods associated with the keyboard, pointing device, voice, and other
input APIs. [Priority 1]
- Note: This checkpoint does not require developers to
implement all operating system input APIs, only to make the software accessible
through those they do implement. Developers are not required to reimplement
input methods of APIs, e.g., text input through a mouse API or pointer motion
through a keyboard API.
-
May require developer documentation
- Mac IE 5.0 (shipped 27 March 2000).: No. But third-party software gives
keyboard access.
- Microsoft Internet Explorer 5.0 for MS-Windows provides extensive keyboard
and mouse support but does not provide device-independent access to
all functionalities.
- Opera 4.0 for MS-Windows provides extensive keyboard and mouse support but
does not provide device-independent access to all functionalities.
From the Opera keyboard navigation
page: "Most operations in Opera can be executed by using the
keyboard."
- MS Internet Explorer5.5 and MicroSoft Office 2000 provide this
functionality.
- 1.2
Use the standard input and output APIs of the operating system. Do not bypass
the standard output APIs when rendering information. [Priority 1]
- Note: For example, do not bypass (for
reasons of speed, efficiency, etc.) standard APIs to manipulate the memory
associated with rendered content, since assistive technologies may monitor
rendering through the APIs. When available, developers should use APIs at a
higher level of abstraction than the standard device APIs for the operating
system. If these higher level APIs do not use the standard device APIs
properly, developers should also use the standard device APIs.
-
May require developer documentation
- 1.3 Implement the operating system's
standard API for the keyboard and ensure that every functionality available
through the user interface is available through this API.
[Priority 1]
- Note: This checkpoint is an important special case of checkpoint 1.1. Refer also to checkpoint
9.8.
-
May require developer documentation
- Mac IE 5.0 (shipped 27 March 2000).: Yes, you could operate the UA by
sending keyboard events to it (this would be a hack, however, since you
shouldn't do this through the OS. If the OS lets you send events, you can do
it).
- Microsoft Internet Explorer 5.0 for MS-Windows provides extensive keyboard
support but does not provide keyboard access to all
functionalities.
- Opera 4.0 for MS-Windows provides extensive keyboard and mouse support but
does not provide device-independent access to all functionalities.
From the Opera keyboard navigation
page: "Most operations in Opera can be executed by using the
keyboard."
Checkpoints for user interface accessibility:
-
1.4 Ensure that the user can interact with all active elements in a
device-independent manner. [Priority 1]
- Note: For example, users without a pointing device (such
as some users who are blind or have physical disabilities) must be able to
activate form controls and links (including the links in a client-side image
map). This checkpoint is an important special case of checkpoint 1.1.
-
May require developer documentation
- Mac IE 5.0 (shipped 27 March 2000).: Yes, to anything you can set
"tabindex" on.
- Microsoft Internet Explorer 5.0 for MS-Windows: links and form
controls
- Netscape Navigator 4.x for MS-Windows: links and form controls
- Operasoft Opera 3.6 for MS-Windows: links and form controls
- No known native support for device independent access to elements that can
respond to scripting events.
- 1.5 Ensure that every message (e.g., prompt,
alert, notification, etc.) that is a non-text element and is part of the user
agent user interface has a text equivalent. [Priority 1]
- Note: For example, if the user is
alerted of an event by an audio cue, a visually-rendered text equivalent in the
status bar would satisfy this checkpoint. Per checkpoint 5.4, a text equivalent for each such message must
be available through a standard API.
Refer also to checkpoint 5.5.
-
May require developer documentation
- Mac IE 5.0 (shipped 27 March 2000).: No, not every button on the tool bar
has a text entry in a menu.
Checkpoints for content accessibility:
- 2.1 Make all content available
through the user interface. [Priority 1]
- Note: Users must have access to the
entire document object through the user interface, including recognized
equivalents, attributes, style sheets, etc. This checkpoint does not require
that all content be available in every viewport. A document source view is an
important part of a solution for providing access to content, but is not a
sufficient solution on its own for all content. Refer to guideline 5 for more
information about programmatic access to content.
-
May require developer documentation
- Mac IE 5.0 (shipped 27 March 2000).: Yes. A source view is available. You
can also get to things from the DOM (which is available through the UI via
javascript:).
- Microsoft Internet Explorer 5.0 provides access to some element attributes
through context menus ("title" attribute used for tooltips)
- NN 4.61 on Linux: No, since attribute values not readily available and no
support for longdesc. For HTML, "alt" is available as visual tool tip.
- Amaya allows users to view content and attribute
values.
- Source view:
- Netscape Navigator 4.75 for Windows, Macintosh and UNIX provides a source
view and "standard" view
- Microsoft Internet Explorer 5.0 for Windows and Macintosh provides a source
view and "standard" view
- Opera 4.0 for Windows provides a source view and "standard" view
- 2.2 For a presentation that requires
user input within a specified time interval, allow the user to configure the
user agent to pause the presentation automatically and await user input before
proceeding. [Priority 1]
- Note: In this configuration, the user
agent may have to pause the presentation more than once, depending on the
number of times input is requested.
-
- Mac IE 5.0 (shipped 27 March 2000).: N/A.
- Real Player 7 (Version 6.0.7.362) Users can pause and resume (or restart)
presentations as needed. No control over configuring pauses or slowing down
presentation speed, however.
- 2.3 Provide easy access to each
equivalent and each equivalency target through at least one of the following
mechanisms: (1) allowing configuration to render the equivalent instead of the
equivalency target; (2) allowing configuration to render the equivalent in
addition to the equivalency target; (3) allowing the user to select the
equivalency target and then inspect its equivalents; (4) providing a direct
link to the equivalent in content, just before or after the equivalency target
in document order. [Priority 1]
- Note: For example, if an image in an
HTML document has text equivalents, provide access to them (1) by replacing the
image with the rendered equivalents, (2) by rendering the equivalents near the
image, (3) by allowing the user to select the image and then inspect its
equivalents, or (4) by allowing the user to follow readily available links to
the equivalents.
-
- Mac IE 5.0 (shipped 27 March 2000).: Yes, through the source view.
- Real Player G2 and Real Player 7 (Version 6.0.7.362) allow users to select
captions based on natural language.
- Real Player 8 includes an accessibility features menu in the Content
preferences to select from among captions or auditory descriptions when they
are present.
- allowing configuration to render the equivalent instead of the equivalency
target:
- Netscape Navigator 4.75 for Windows, Macintosh and UNIX
- Microsoft Internet Explorer 5.0 for Windows and Macintosh
- Opera 4.0 for Windows
-
2.4 Allow the user to specify that text transcripts, collated text
transcripts, captions, and auditory descriptions be rendered at the same time
as the associated audio and visual tracks. Respect author-specified
synchronization cues during rendering. [Priority 1]
-
- Real Player G2 for Windows and Mac
- Microsoft Media Player
- 2.5 For non-text content that has no
recognized text equivalent, allow configuration to generate repair text. If the
non-text content is included by URI reference, base the repair text on the URI
reference and content type of the Web resource. Otherwise, base the repair text
on the name of the element that includes the non-text content.
[Priority 2]
- Note: For information on URI references, refer to "Uniform
Resource Identifiers (URI): Generic Syntax" ([RFC2396], section 4). Some markup
languages (such as HTML 4 [HTML4] and SMIL 1.0 [SMIL] require the
author to provide text equivalents for some content. When they don't, the user
agent is required by this document to generate repair text. Refer also to checkpoint 2.6.
-
- Mac IE 5.0 (shipped 27 March 2000).: No. MacIE may not repair broken markup
because not required to by HTML specification.
- Lynx renders the text "IMAGE" when no text equivalent is available for an
HTML IMG element.
- Opera 3.60 for MS-Windows renders the text "IMAGE" when no text equivalent
is available for an IMG element.
- 2.6 Allow configuration so that when the author
has specified an empty text equivalent for non-text content, the user agent
generates no repair text or generates repair text as required by checkpoint 2.5.
[Priority 3]
- Note: An empty text equivalent (e.g.,
alt=""
)
is considered to be a valid text equivalent in some authoring scenarios. For
instance, when some non-text content has no other function than pure
decoration, or an image is part of a "mosaic" of several images and doesn't
make sense out of the mosaic. Please refer to the Web Content Accessibility
Guidelines 1.0
[WCAG10] for more information about text equivalents. Refer also to checkpoint 2.5.
-
- Mac IE 5.0 (shipped 27 March 2000).: Yes.
- Amaya seems to do this correctly for "alt".
-
2.7 Allow the user to configure the user agent not to render content
marked up in a recognized but unsupported natural language. Indicate to the
user in context that author-supplied content has not been rendered.
[Priority 3]
- Note: For example, use a text
substitute or a graphical icon to indicate that content in a particular
language has not been rendered. If a graphical icon is used, make the text
substitute its text equivalent.
-
- Mac IE 5.0 (shipped 27 March 2000).: Yes, CSS :lang supported, other style
may be used. :before not supported. Can use color, underlining, etc.
Checkpoints for content accessibility:
-
3.1 Allow the user to configure the user agent not to render
background images. In this configuration, provide an option to alert the user
when a background image is available but has not been rendered.
[Priority 1]
- Note: This checkpoint only requires control of background
images for "two-layered renderings", i.e., one rendered background image with
all other content rendered "above it". When background images are not rendered,
user agents should render a solid background color (refer to checkpoint 4.4 and
checkpoint 4.3).
In this configuration, the user agent is not required to retrieve background
images from the Web.
-
- Mac IE 5.0 (shipped 27 March 2000).: Yes.
- Turn off all pictures (UI)
- More granularity through user style sheet:
* { background-image: none
! important}
- Microsoft Internet Explorer 5.0 for MS-Windows
- Netscape Navigator 4.x for MS-Windows
- Operasoft Opera 3.60 for MS-Windows
- NN 4.61 for Linux: Yes, through style sheets or in the default file with
*defaultBackgroundImage.
- Amaya allows users to turn off background image rendering through Show background
images and style sheets.
- 3.2
Allow the user to configure the user agent not to render audio, video, or
animated images except on explicit request from the user. In this
configuration, provide an option to render a substitute placeholder in context
for each unrendered source of audio, video, or animated image. When
placeholders are rendered, allow the user to activate each placeholder
individually and replace it with the original author-supplied content.
[Priority 1]
- Note: This checkpoint requires configuration for content
rendered without any user interaction (including content rendered on load or as
the result of a script) as well as content rendered as the result of user
interaction that is not an explicit request (e.g., when the user activates a
link). Activation of a placeholder is considered an explicit user request to
render the original content. When configured not to render content except on
explicit user request, user agents may render the content "invisibly" or
"silently" (i.e., in a manner that doesn't appear through the viewport). In
this configuration, the user agent is not required to retrieve the audio,
video, or animated image from the Web until requested by the user. Refer also
checkpoint 4.6, checkpoint 4.10 and checkpoint
4.11.
- Unknown.
- 3.3
Allow the user to configure the user agent to render animated or blinking text
as motionless text. [Priority 1]
-
- Mac IE 5.0 (shipped 27 March 2000).: Yes. MacIE 5 does not allow blinking
text at all. You can turn off scripting. And you have 'display: none'.
- Microsoft Internet Explorer 5.0 for MS-Windows does not recognize
proprietary markup for blinking text but does allow the user to turn off
scripts that could be blinking text.
- Operasoft Opera 3.60 for MS-Windows does not recognize proprietary markup
for blinking text and allows the user to turn off scripts and style sheets that
could cause text to be animated.
- NN 4.61 Linux: Yes, through the defaults file, set "*blinkingEnables:
False".
- Amaya, for blinking accomplished through style sheets.
-
3.4 Allow the user to configure the user agent to render blinking
images as motionless images. [Priority 1]
-
- Mac IE 5.0 (shipped 27 March 2000).: Yes. You can turn scripts off. You can
make animations stop looping OR not animate at all.
- Microsoft Internet Explorer 5.0 for MS-Windows
- Operasoft Opera 3.60 for MS-Windows
- NN 4.61 for Linux: Yes, through Preferences/Advanced menus. Enable Java and
JavaScript. Also, possible to turn off images.
- 3.5 Allow the user to configure the user
agent not to execute scripts or applets. In this configuration, provide an
option to alert the user when scripts or applets are available.
[Priority 1]
-
- Mac IE 5.0 (shipped 27 March 2000).: Yes to scripts and applets, plug-ins,
active-x.
- Netscape Navigator 4.x for MS-Windows
- Operasoft Opera 3.60 for MS-Windows
- NN 4.61 for Linux: Yes, through the user interface
(Preferences/Advanced).
-
3.6 Allow configuration so that an author-specified "client-side
redirect" (i.e., one initiated by the user agent, not the server) does not
change content except on explicit user request. Allow the user to access the
new content manually (e.g., by following a link). [Priority 2]
-
- Mac IE 5.0 (shipped 27 March 2000).: No.
-
3.7 Allow configuration so that author-specified content refreshes
do not change content except on explicit user request. Allow the user to
request the new content manually (e.g., by activating a button or following a
link). Continue to alert the user, according to schedule specified by the
author, that a manual request will refresh the content. [Priority 2]
-
- Mac IE 5.0 (shipped 27 March 2000).: Yes, through work offline mode and
address unavailable error dialog.
- No information available.
- 3.8 Allow the user to configure the user
agent not to render images. [Priority 2]
-
- Mac IE 5.0 (shipped 27 March 2000).: Yes.
- Microsoft Internet Explorer 5.0 for MS-Windows
- Netscape Navigator 4.x for MS-Windows
- Operasoft Opera
3.60 for MS-Windows
- NN 4.61 for Linux: Yes.
- Amaya, through style sheets at least.
Checkpoints for fonts and colors (content accessibility):
- 4.1
Allow the user to configure and control the reference size of rendered text
with an option to override author-specified and user agent default sizes of
rendered text. Make available the range of system font sizes.
[Priority 1]
- Note: The reference size of rendered
text corresponds to the default value of the CSS2 'font-size' property, which
is 'medium' (refer to CSS2 [CSS2], section 15.2.4). The default
reference size of rendered text may vary among user agents. User agents may
offer different mechanisms to allow the user to control the size of rendered
text, for example by allowing the user to change the font size or by allowing
the user to zoom or magnify content (refer, for example to the Scalable Vector
Graphics specification
[SVG]).
-
- Mac IE 5.0 (shipped 27 March 2000).: Yes, zoom and font size control. Also
DPI control.
- Microsoft Internet Explorer 5.0 for MS-Windows
- Netscape Navigator 4.x for MS-Windows
- Operasoft Opera 3.60 for MS-Windows. Zoom feature.
- pwWebSpeak 3.0: Lets you increase and decrease the display size (refer to
help).
- NN 4.61 for Linux: Yes, through style sheets and the user interface
(Preferences/Appearances/Fonts).
- Amaya through style
sheets
- Microsoft
Magnifier is part of the MSAA toolkit.
-
4.2 Allow the user to configure the font family of all text, with an
option to override author-specified, and user agent default, font families.
Allow the user to select from among the range of system font families.
[Priority 1]
- Note: For example, allow the user to
specify that all text must be rendered in a particular sans-serif font
family.
-
- Mac IE 5.0 (shipped 27 March 2000).: Yes. Also, you can set a global font
family preference.
- Microsoft Internet Explorer 5.0 for MS-Windows
- Netscape Navigator 4.x for MS-Windows
- Operasoft Opera 3.60 for MS-Windows
- pwWebSpeak 2.5 for MS-Windows
- NN 4.61 for Linux: Yes, through style sheets and the user interface
(Preferences/Appearances/Fonts).
- Amaya through style
sheets
-
4.3 Allow the user to configure the foreground color of all text,
with an option to override author-specified, and user agent default, foreground
colors. Allow the user to select from among the range of system colors.
[Priority 1]
-
- Mac IE 5.0 (shipped 27 March 2000).: Yes. Also user style sheets.
- Microsoft Internet Explorer 5.0 for MS-Windows
- Netscape Navigator 4.x for MS-Windows
- Operasoft Opera 3.60 for MS-Windows
- pwWebSpeak 3.0: Lets you choose from among pre-set foreground colors (refer
to help).
- NN 4.61 for Linux: Yes, through style sheets, the user interface
(Preferences/Appearance/Fonts), and, for text, in the defaults file
(*defaultForeground).
- Amaya through style
sheets
-
4.4 Allow the user to configure the background color of all text,
with an option to override author-specified and user agent default background
colors. Allow the user to select from among the range of system colors.
[Priority 1]
-
- Mac IE 5.0 (shipped 27 March 2000).: Yes. Also user style sheets.
- Microsoft Internet Explorer 5.0 for MS-Windows
- Netscape Navigator 4.x for MS-Windows
- Operasoft Opera 3.60 for MS-Windows
- pwWebSpeak 3.0: Lets you choose from among pre-set background colors (refer
to help).
- NN 4.61 for Linux: Yes, through style sheets, the user interface
(Preferences/Appearance/Fonts), and, for text, in the defaults file
(*defaultBackground).
- Amaya through style
sheets
Checkpoints for
multimedia presentations, audio-only presentations, and
visual-only presentations (content accessibility):
- 4.5 Allow the user to slow the
presentation rate of audio, video and animations that are not recognized as
style. For a visual track, provide at least one setting between 40% and 60% of
the original speed. For a prerecorded audio track including audio-only
presentations, provide at least one setting between 75% and 80% of the original
speed. When the user agent allows the user to slow the visual track of a
synchronized multimedia presentation to between 100% and 80% of its original
speed, synchronize the visual and audio tracks. Below 80%, the user agent is
not required to render the audio track. [Priority 1]
- Refer also to
checkpoint 2.4.
-
- Mac IE 5.0 (shipped 27 March 2000).: Animations: No. Video: N/A. Audio:
MACIE handles "bgsound". No ACSS support.
- Real Player G2? (CMN thinks it doesn't).
- Microsoft Media Player
- 4.6 Allow the user to stop, pause,
resume, fast advance, and fast reverse audio, video, and animations that last
three or more seconds at their default playback rate and that are not
recognized as style. [Priority 1]
- Note: This checkpoint applies to
content that is rendered automatically or on request from the user. Enable
control of each independent source recognized as distinct. Respect
synchronization cues per checkpoint 2.4. Refer also to checkpoint 3.2.
-
- Mac IE 5.0 (shipped 27 March 2000).: Functionality satisfied by a plug-in
that for audio and video meets this requirement. No for animations.
- Real Player G2 and Real Player 7 (Version 6.0.7.362)
- Microsoft Media Player
- 4.7 For graphical viewports, allow
the user to position text transcripts, collated text transcripts, and captions
in the viewport. Allow the user to choose from among the same range of
positions available to the author (e.g., the range of positions allowed by the
markup or style language). [Priority 1]
-
- Mac IE 5.0 (shipped 27 March 2000).: N/A.
- No information available.
-
4.8 Allow the user to slow the presentation rate of audio, video and
animations not covered by
checkpoint 4.5. The same speed percentage requirements of checkpoint 4.5 apply.
[Priority 2]
- Note: User agents automatically satisfy
this checkpoint if they satisfy
checkpoint 4.5 for every audio, video, and animation.
- none.
-
4.9 Allow the user to stop, pause, resume, fast advance, and fast
reverse audio, video, and animations not covered by checkpoint 4.6.
[Priority 2]
- Note: User agents automatically satisfy
this checkpoint if they satisfy checkpoint 4.6 for every audio, video, and animation.
- None.
Checkpoints for audio volume control (content accessibility):
-
4.10 Allow the user to configure and control the global audio
volume. The user must be able to choose zero volume (i.e., silent).
[Priority 1]
- Note: User agents should allow global
control of volume through available system-level controls.
-
- Mac IE 5.0 (shipped 27 March 2000).: Yes, through system. Available through
UA. Mute available.
- Real Player G2 and Real Player 7 (Version 6.0.7.362)
- Microsoft Media Player
-
4.11 Allow the user to control independently the volumes of distinct
audio sources synchronized to play simultaneously. [Priority 1]
- Note: Refer also to checkpoint 4.13.
-
- Mac IE 5.0 (shipped 27 March 2000).: Yes, you have volume control per audio
source (except for background sounds).
- IE with Windows Media Player supports independent volume control of
distinct audio sources (refer to minutes of 22
June 2000 teleconf.
- Henter-Joyce JAWS 3.31 for MS-Windows
- GW-Micro Windoweyes 3.0 for MS-Windows
- AI-Squared Zoomtext 7.0 Level 2 for MS-Windows
Checkpoints for synthesized speech (content accessibility):
-
4.12 Allow the user to configure and control synthesized speech
playback rate according to the full range offered by the speech synthesizer.
The lower bound for this range must be at most 120 words per minute. The upper
bound for this range must be at least 400 words per minute. The user must be
able to increase or decrease the playback rate in increments of 5% of the
current playback rate. [Priority 1]
-
- Mac IE 5.0 (shipped 27 March 2000).: N/A.
- Henter-Joyce JAWS 3.70.47 for MS-Windows Using the Voice option it is
possible to increase or decrease the rate of the spoken text. The speech rate
range depends on the synthesizer used and is even marked up differently
depending on the synth/driver used. For example, with DecTalk Access 32
software, the rate can be varied from 75 to 650 words per minute.
- pwWebSpeak 3.0: Lets you choose increase and decrease the speech rate
through keyboard bindings.
- GW-Micro Window-Eyes 3.0 for MS-Windows
- AI-Squared Zoomtext 7.0 Level 2 for MS-Windows
- Emacspeak, through ACSS.
-
4.13 Allow the user to control the synthesized speech volume
independently of other sources of audio. [Priority 1]
- Note: Refer also to checkpoint 4.11.
-
- Window-Eyes fromGW Micro claims
support for volume control: "Set up the speech rate, pitch, tone, volume and
punctuation independently for screen, keyboard, and mouse"
-
4.14 Allow the user to configure synthesized voice gender, pitch,
pitch range, stress, richness, and control of spelling, punctuation, and number
processing according to the full range of values offered by the speech
synthesizer. [Priority 2]
- Note: Ranges of values for these
characteristics may vary among speech synthesizers. For information about these
synthesized speech characteristics, please refer to descriptions in section
19.8 of Cascading Style Sheets Level 2 [CSS2].
-
- Mac IE 5.0 (shipped 27 March 2000).: N/A.
- Henter-Joyce JAWS 3.31 for MS-Windows
- AI-Squared Zoomtext 7.0 Level 2 for MS-Windows
- Emacspeak used with the W3 browser implement Aural Cascading Style Sheets
(19.8 of Cascading Style Sheets Level 2 [CSS2]). From the
Emacspeak 12 FAQ:
Emacspeak takes advantage of the content-specific knowledge available within
specialized buffers to produce "audio formatted" output designed to optimize
user interaction. A basic consequence of the above is "voice locking" in
specialized modes; a more interesting consequence is the implementation of
Aural Cascading Style Sheets (ACSS) in conjunction with the Emacs W3
browser.
- Window-Eyes 4.0 from GW Micro claims
support for volume control: "Set up the speech rate, pitch, tone, volume and
punctuation independently for screen, keyboard, and mouse". Also: "Allows
speech to be interrupted or silenced with the press of a key". Also: "Numbers
can be spoken as digits or full numbers "
Checkpoints for user interface accessibility:
- 4.15
For user agents that support style sheets, allow the user to select from (and
apply) available author and user style sheets or to ignore them.
[Priority 1]
- Note: By definition, the user agent's default style sheet
is always present, but may be overridden by author or user styles.
-
- Mac IE 5.0 (shipped 27 March 2000).: You can turn off all author and user
style sheets. You can turn on author style sheets. With a javascript addition,
you can choose from alternate author styles (per page). You can choose from
user-defined style globally.
- Microsoft Internet Explorer 5.0 for MS-Windows
- Operasoft 3.60 for MS-Windows
- NN 4.61 for Linux: Turn of author styles only, through
Preferences/Advanced: style sheets.
- Amaya allows you to select style sheets,
disable, remove, open, link, etc.
- 4.16 Allow the user to
configure how the selection is highlighted (e.g., foreground and background
color, voice pitch, etc.). For graphical viewports, offer at least three
rendering options, including colors and fonts. Allow the user to select from
among the range of system colors and fonts. [Priority 1]
- Note: For information for control of speech output and
using those parameters for highlighting, refer to checkpoint 4.14.
-
- Mac IE 5.0 (shipped 27 March 2000).: Yes, you can set selection color at
the system level on the Mac. You can't have a selection that's identified by
something other than color.
- Microsoft Internet Explorer 5.0 for MS-Windows Windows 9x settings for
highlight, which can be set by the user.
- NN 4.61 for Linux: Yes, in the defaults file set *selectForeground and
*selectBackground.
-
4.17 Allow the user to configure how the content focus is
highlighted (e.g., foreground and background color, voice pitch, etc.). For
graphical viewports, offer at least three rendering options, including colors
and fonts. For graphical viewports, allow the user to select from among the
range of system colors and fonts. The default focus highlight mechanism must be
different from the default selection highlight mechanism.
[Priority 1]
- Note: For information for control of speech output and
using those parameters for highlighting, refer to checkpoint 4.14.
-
- Mac IE 5.0 (shipped 27 March 2000).: Yes. You can change the color of the
focus rectangle. Also, UA supports CSS ":focus"
:focus {background: black
! important; color: white ! important }
- Operasoft 3.60 for MS-Windows
-
4.18 Allow the user to configure whether the current focus moves
automatically to a viewport that opens without an explicit request from the
user. [Priority 2]
-
- Mac IE 5.0 (shipped 27 March 2000).: You can turn off javascript (even
per-site). Note that the UA supports the "target" attribute.
- No information available.
-
4.19 Ensure that when a viewport's selection or content focus
changes, it is in the viewport after the change. [Priority 2]
- Note: For example, if users navigating
links move to a portion of the document outside a graphical viewport, the
viewport should scroll to include the new location of the focus. Or, for users
of audio viewports, allow configuration to render the selection or focus
immediately after the change.
-
- Microsoft Internet Explorer 5.0 for MS-Windows
- Netscape Navigator 4.x for MS-Windows
- Operasoft Opera 3.60 for MS-Windows
- 4.20 Allow the user to configure the
user agent to only open viewports on explicit user request. In this
configuration, instead of opening a viewport automatically, alert the user and
allow the user to open it manually. Allow the user to close viewports.
[Priority 2]
- Note: User creation of a new viewport (e.g., empty or with
a new resource loaded) through the user agent's user interface constitutes an
explicit user request. Refer also to checkpoint 4.18 and checkpoint 5.5.
-
- Mac IE 5.0 (shipped 27 March 2000).: Yes, you can turn off javascript.
- NN 4.61 for Linux: Partial support. In the defaults file, the
*dontForceWindowStacking resource allows one to suppress some automatic window
stacking caused by JavaScript window.open().
- 4.21 For graphical user interfaces,
allow the user to configure the user agent so that the viewport with the
current focus remains "on top" of all other viewports. In this configuration,
when a viewport opens without explicit user request, alert the user.
[Priority 2]
- None.
Checkpoints for communication with other software:
- 5.1 Provide programmatic read access to
HTML and XML content by conforming to the
W3C Document Object Model (DOM) Level 2 Core and
HTML Specifications and exporting the interfaces they define.
[Priority 1]
- Note: These specifications are defined
by the "Document Object Model (DOM) Level 2 Core Specification" [DOM2CORE]
and the "Document Object Model (DOM) Level 2 HTML Specification" [DOM2HTML].
Please refer to those specifications for information about which versions of
HTML and XML the specifications cover and
for the definition of a "read-only" DOM. For content other
than HTML and XML, refer to
checkpoint 5.3.
-
May require developer documentation
- For DOM Level 2 XML support:
-
- For DOM Level 2 HTML support:
-
- Additional information:
-
- Microsoft Internet Explorer 5.0 for MS-Windows provides access to the DOM
through a COM interface. We have not verified whether the implementation
conforms to the DOM specification.
- 5.2 If the user can modify
HTML and XML content through the user interface, provide the same
functionality programmatically by conforming to the W3C Document Object Model
(DOM) Level 2 Core and
HTML Specifications and exporting the interfaces they
define. [Priority 1]
- Note: For example, if the user
interface allows users to complete HTML forms, this must
also be possible through the DOM APIs. These specifications
are defined by the "Document Object Model (DOM) Level 2 Core Specification"
[DOM2CORE] and the "Document Object Model (DOM) Level 2 HTML
Specification" [DOM2HTML]. Please refer to those
documents for information about which versions of HTML and
XML the specifications cover. For markup languages other
than HTML and XML, refer to
checkpoint 5.3.
-
May require developer documentation
Refer to checkpoint 5.1
information.
- 5.3 For markup languages other than
HTML and XML, provide programmatic access to content using
standard APIs (e.g., platform-independent APIs and standard
APIs for the operating system). [Priority 1]
- Note: This checkpoint addresses content
not covered by checkpoints
checkpoint 5.1 and
checkpoint 5.2.
-
May require developer documentation
- 5.4 Provide programmatic read and write
access to user agent user interface controls using standard APIs (e.g.,
platform-independent APIs such as the W3C DOM; standard APIs
defined for a specific operating system; and conventions for programming
languages, plug-ins, virtual machine environments, etc.) [Priority 1]
- Note: For example, provide access to
information about the user agent's current input configuration so that
assistive technologies can trigger functionalities through keyboard events,
mouse events, etc.
-
May require developer documentation
- Mac IE 5.0 (shipped 27 March 2000).: Mostly (except for a handful of
functionalities that can be fixed). There is no explicit accessibility API for
the Mac. If you use the standard toolkit, there are accessibility APIs.
- Microsoft Internet Explorer 5.0 for MS-Windows provides access through
Microsoft Active Accessibility. From a Microsoft
claim:
Internet Explorer 5 features improved support for Microsoft Active
Accessibility®, a technology developed by Microsoft that allows
accessibility aids to communicate with the operating system and applications
through a common interface. Although this technology isn't visible to the end
user, developers of accessibility aids use Active Accessibility to make aids
such as screen readers, screen magnifiers, and speech input tools work better
with the operating system and applications.
- 5.5 Using standard APIs, provide programmatic
alert of changes to content and user interface controls (including selection,
content focus, and user interface focus). [Priority 1]
- Note: Use the standard APIs required by
guideline 5.
-
May require developer documentation
- Mac IE 5.0 (shipped 27 March 2000).: Yes.
- For UI controls, ATs can override the system behavior and then call through
to it (effectively acting as a hook).
- Content changes handled by the DOM.
- Microsoft Internet Explorer 5.0 for Windows provides access through
Microsoft Active Accessibility.
- Refer to the Xerces tool support for DOM Level 2 Mutation events, available
from the Apache XML project.
- Refer to the DOM2
implementation support for mutation events.
- Refer to Jackaroo (a
Scalable Vector Graphics viewer) for DOM support for
mutation events.
- Additional W3C Member-confidential information about conformance to DOM
Level 2 modules is available.
- 5.6 Ensure that programmatic exchanges
proceed in a timely manner. [Priority 2]
- Note: For example, the programmatic
exchange of information required by other checkpoints in this document must be
efficient enough to prevent information loss, a risk when changes to content or
user interface occur more quickly than the communication of those changes. The
techniques for this checkpoint explain how developers can reduce communication
delays, e.g., to ensure that assistive technologies have timely access to the
document object model and other information needed for accessibility.
-
May require developer documentation
- 5.7 For user agents that implement
Cascading Style Sheets (CSS), provide programmatic access to
CSS style sheets by conforming to the W3C Document Object
Model (DOM) Level 2 Style
Specification and exporting the interfaces it defines. [Priority 3]
- Note: As of the publication of this
document, Cascading Style Sheets (CSS) are defined by CSS
Level 1
[CSS1] and CSS Level 2 [CSS2]. The DOM style specification
is defined by "Document Object Model (DOM) Level 2 Style Specification"
[DOM2STYLE]. Please refer to that specification for information
about which versions of CSS the DOM style specification
covers.
-
May require developer documentation
- Mac IE 5.0 (shipped 27 March 2000).: Claims to support some of the CSSOM
available in the Candidate Recommendation and to support string access to all
of the properties (CSS2 extensions).
- Refer to Jackaroo (a
Scalable Vector Graphics viewer) for DOM access to CSS 1
[CSS1].
- Additional W3C Member-confidential information about conformance to DOM
Level 2 modules is available.
Checkpoints for user interface accessibility:
- 5.8 Follow operating system conventions
that benefit accessibility. In particular, follow conventions for user
interface design, keyboard configuration, product installation, and
documentation. [Priority 2]
- Note: Operating system conventions that benefit
accessibility are those described in this document and in platform-specific
accessibility guidelines. Some of these conventions (e.g., sticky keys, mouse
keys, show sounds, etc.) are discussed in the Techniques document
[UAAG10-TECHS]. Refer also to checkpoint 9.2.
-
Checkpoints for content accessibility:
-
6.1 Implement the accessibility features of all implemented
specifications (markup languages, style sheet languages, metadata languages,
graphics formats, etc.). The accessibility features of a specification are
those identified as such and those that satisfy all of the
requirements of the "Web Content Accessibility Guidelines 1.0" [WCAG10].
[Priority 1]
-
May require developer documentation
- Mac IE 5.0 (shipped 27 March 2000).:
- Supported 100%:
- CSS1, HTML 3.2, HTML 4.0, "DOM 1.0 HTML", PNG 1.0, EcmaScript 262, PICS
1.0
- Supported Mostly (informative):
- XML 1.0, XML + CSS, XML + DOM 1, DOM 2 style.
- Supposed Somewhat (informative):
- CSS2 (full positioning, all selectors but attribute selectors, full ui
support, font downloading supported, @import with media type, not @media, no
explicit table properties supported, no generated content, no counters, some
printing properties, no ACSS).
- Real Player 7 (Version 6.0.7.362) implements SMIL 1.0
- 6.2 Use and conform to W3C
Recommendations when they are available and appropriate for a task.
[Priority 2]
- Note: For instance, for markup, conform
to HTML 4 [HTML4], XHTML 1.0 [XHTML10], or
XML 1.0 [XML]. For style sheets, conform to
CSS ([CSS1], [CSS2]). For mathematics, conform to
MathML
[MATHML]. For synchronized multimedia, implement
SMIL 1.0
[SMIL]. For information about programmatic access to
HTML and XML content, refer to guideline 5. User agents may
conform to other specifications in addition to those required by this
checkpoint. For reasons of backward compatibility, user agents should continue
to implement deprecated features of specifications. Information about
deprecated language features is generally part of the language's
specification.
-
May require developer documentation
- Mac IE 5.0 (shipped 27 March 2000).: Yes, see list in 6.1
- Amaya does this for DOM, CSS, HTML, and MathML.
Checkpoints for user interface accessibility:
- 7.1 Allow the user to navigate among all
viewports (including frames). [Priority 1]
- Note: For example, when all frames of a
frameset are displayed side-by-side, allow the user to navigate among them with
the keyboard. Or, when frames are accessed or viewed one at a time (e.g., by a
text browser or speech synthesizer), provide a list of links to other frames.
Navigation among all viewports implies at least allowing the user to cycle
through all viewports. Navigating into a viewport makes it the current
viewport.
-
- Mac IE 5.0 (shipped 27 March 2000).: Yes, for windows (at both UA and OS
level). No for frames.
- Lynx for UNIX (for frames).
- Microsoft Internet Explorer 5.0 for MS-Windows (for frames: refer to Help
"Frames | Navigating").
- Operasoft Opera 4.01
for MS-Windows (for frames).
- NN 4.75 for Windows: You can tab to links in all frames, but not to a
specific frame with through the keyboard.
- pwWebSpeak 3.0: Offers a list of frames.
- NN 4.61 for Linux: Yes: View/Page Source for frames in a single window.
Navigation possible with the mouse. Navigation of history possible with a
history window, a pulldown menu, and arrow icons (also possible with keyboard).
Navigation of windows is done through the window manager (Alt-Tab in
my configuration). It is not possible to navigate links sequentially in NN on
Linux.
-
7.2 Associate a point of regard with each state in a viewport's
browsing history and when the user returns to a state in the history, restore
the associated point of regard. [Priority 1]
- Note: For example, when the user
navigates from one viewport to another (per checkpoint 7.1) and back, restore the point of regard.
-
- Mac IE 5.0 (shipped 27 March 2000).: Yes. And focus is restored!
- Lynx for UNIX (for frames).
- Microsoft Internet Explorer 5.0 for MS-Windows, but a problem with frames.
Point or Regard is frame not link within frame, does not remember highlighted
text.
- Operasoft Opera 4.01
for MS-Windows, even within each frame.
- pwWebSpeak 3.0: Yes, even within each frame.
- 7.3 Allow the user to navigate all active
elements. If the author has not specified a navigation order, allow at least
forward sequential navigation of elements, in document order.
[Priority 1]
- Note: Navigation may include non-active
elements in addition to active elements. This checkpoint is an important
special case of checkpoint
7.6.
-
- Mac IE 5.0 (shipped 27 March 2000).: Yes, for HTML, things with
tabindex.
- Microsoft Internet Explorer 5.0 for MS-Windows, only for links and form
controls. See Help "Keyboard Shortcuts".
- NN 4.75 for Windows: You can tab to links in all frames, but not to a
specific frame with through the keyboard.
- Operasoft Opera 4.01
for MS-Windows, see Help "Keyboard Shortcuts".
- pwWebSpeak 3.0: Yes, see help.
- 7.4 Allow the user to choose to navigate
only active elements. If the author has not specified a navigation order, allow
at least forward and reverse sequential navigation of active elements, in
document order. [Priority 2]
-
- Mac IE 5.0 (shipped 27 March 2000).: For HTML, things with tabindex.
- Microsoft Internet Explorer 5.0 for MS-Windows, only for links and form
controls. See Help "Keyboard Shortcuts".
- NN 4.75 for Windows: You can navigate to only active elements.
- NN 4.61 for Linux: No.
- Operasoft Opera 4.01
for MS-Windows, see Help "Keyboard Shortcuts".
- pwWebSpeak 3.0: Yes, see help.
- 7.5 Allow the user to search forward through
text content that has been rendered. The search must encompass all text within
the viewport, both inside and outside the point of regard. Allow the user to
start a search from any selected or focused location in content. When there is
a match, allow the user to search for the next instance of the text from the
location of the match. When there is a match, move the point of regard so that
the matched text is in the viewport. Alert the user when there is no match.
Provide a case-insensitive search option when applicable to the natural
language of text. [Priority 2]
- Note: The default search starting point should be the
beginning of content. Use operating system conventions for indicating the
result of a search (e.g., selection or content focus).
-
- Mac IE 5.0 (shipped 27 March 2000).: Forward, yes, but some information
only available in the source view. Case-insensitive option. No reverse search
available.
- Operasoft Opera 4.01
for MS-Windows, see Help "Keyboard Shortcuts-Editing and Searching", Not
found Alert=Search String Not Found. Can only search for text within current
viewport - i.e. current frame, cannot search across frames.
- NN 4.75 for Windows: You can tab to links in all frames, but not to a
specific frame with through the keyboard. See Help "Searching", Not found
Alert=Search String Not Found. See help "searching for text on a page", can
search across frames. Not found Alert=Finished Searching the Document
- pwWebSpeak 3.0: Yes - See Help, Alert=x was not found. Can only search for
text within current viewport - i.e., current frame, cannot search across
frames. pwWebSpeak 2.5 for MS-Windows will search text equivalents.
- 7.6 Allow the user to navigate efficiently
to and among important structural elements identified by the author. Allow
forward and backward sequential navigation to important structural elements.
[Priority 2]
- Note: This specification intentionally
does not identify the set of "important elements" that must be navigable; refer
to the Techniques document [UAAG10-TECHS] for
information about identifying important elements. Structured navigation of
headings, tables, forms, lists, etc., is most effective in conjunction with a
configurable view (refer to configuration requirements of checkpoint 8.4 and checkpoint 7.7). User
agents should follow operating system conventions for indicating navigation
progress (e.g., selection or content focus).
-
- Mac IE 5.0 (shipped 27 March 2000).: Not sure.
- Operasoft Opera 4.01
for MS-Windows, see Help "Keyboard Shortcuts", Anchors, Elements,
Headers.
- W3C Amaya for
MS-Windows.
- NN 4.61 for Linux: Only partly – View/Source gives some access to
document structure, but not headings, etc.
- pwWebSpeak 3.0: Lets you navigate by element type and specifically by
heading type (these are pre-specified). See Help Anchors, Elements, Headers
(h1, h2, etc.).
- OPENBook 5.0
supports structured navigation of elements.
- 7.7
Allow the user to configure and control the set of important elements required
by checkpoint 7.6 and checkpoint 8.4. Allow the
user to include and exclude element types in the set of elements.
[Priority 3]
- Note: For example, allow the user to navigate only
paragraphs, or only headings and paragraphs, etc. Refer also to checkpoint 5.4.
-
- Mac IE 5.0 (shipped 27 March 2000).: Not sure.
- No information available.
Checkpoints for content accessibility:
- 8.1 Make available to the user the
author-specified purpose of each table and the author-specified relationships
among the table cells and headers. [Priority 1]
- Note: Depending on the table, some techniques may be more
efficient than others for conveying data relationships. For many tables, user
agents rendering in two dimensions may satisfy this checkpoint by rendering a
table as a grid and by ensuring that users can find headers associated with
cells. However, for large tables or small viewports, allowing the user to query
cells for information about related headers may improve access. Refer also to checkpoint
5.3. This checkpoint is an important special case of checkpoint 2.1.
-
- JAWS for Windows 3.5 with Microsoft Internet Explorer 5.0 for MS-Windows,
for table header information.
- 8.2 Render recently visited links in a
distinct style and allow the user to configure this style. For graphical
viewports, offer at least three rendering options, including colors and fonts.
Allow the user to select from among the range of system colors and fonts.
[Priority 2]
- Note: Do not use color as the only
distinguishing factor between visited and unvisited links as some users may not
perceive colors and some devices may not render them. This checkpoint is an
important special case of checkpoint
8.5.
-
- NN 4.61 for Linux: Yes, colors controllable through style sheets,
*vlinkForeground in the defaults file, and through the UI under
Preferences/Appearance/Colors. From there you can also enable/disable
underlining.
- Amaya yes, through colors at least.
- 8.3 Render in a distinct style those links
that have been marked up to indicate that following them will involve a fee and
allow the user to configure this style. For graphical viewports, offer at least
three rendering options, including colors and fonts. Allow the user to select
from among the range of system colors and fonts. [Priority 2]
- Note: This checkpoint is an important
special case of checkpoint
8.5.
-
- No information available.
- 8.4
Make available to the user an "outline" view of content, composed of labels for
important structural elements (e.g., heading text, table titles, form titles,
etc.). For discussion about what constitutes the set of important structural
elements, please refer to
checkpoint 7.6. [Priority 2]
- Note: This checkpoint is meant to allow
the user to simplify the view of content by hiding some content selectively.
For example, for each frame in a frameset, provide a table of contents composed
of headings (e.g., the H1 - H6 elements in HTML) where each entry in the table
of contents links to the heading in the document. This checkpoint does not
require that the outline view be navigable, but this is recommended; refer to
checkpoint 7.6. For those
elements that do not have associated text titles or labels, the user agent
should generate a brief text label (e.g., from content, the element type,
etc.). Refer also to
checkpoint 7.7.
-
- W3C Amaya for
MS-Windows
- Microsoft Internet Explorer 5.0 for MS-Windows with style sheets.
- Operasoft Opera 3.60 for MS-Windows
- 8.5 To help the user decide whether to
traverse a link, make available the following information about it: link
content, link title, whether the link is internal to the local resource,
whether the user has traversed the link recently, whether traversing it may
involve a fee, and information about the type, size, and natural language of
linked Web resources. The user agent is not required to compute or make
available information that requires retrieval of linked Web resources.
[Priority 3]
-
- Operasoft Opera 3.60 for MS-Windows
- Amaya makes available information about attributes through the attribute
menu.
Checkpoints for user interface accessibility:
-
8.6 Implement selection, content focus, and user interface focus
mechanisms. Implement them according to system conventions (per checkpoint 5.8).
[Priority 1]
- Note: This checkpoints refers to the logical
selection and focus; rendering requirements are addressed by checkpoint 8.7,
checkpoint 4.17,
and checkpoint
4.16. Refer also to checkpoint
7.1.
-
- Most browsers do this (NN, IE, Amaya, Lynx, etc.)
- 8.7 Provide a mechanism
for highlighting the current viewport, selection, and content focus.
[Priority 1]
- Note: This includes highlighting and
identifying frames. This checkpoint is an important special case of checkpoint 1.1. Refer
also to checkpoints checkpoint 4.16, checkpoint 5.8, and checkpoint 8.5.
-
- Microsoft Internet Explorer 5.0 for MS-Windows
- Netscape Navigator 4.x for MS-Windows
- Operasoft Opera 3.60 for MS-Windows
- NN 4.61 for Linux: Yes for selection and viewport, but graphically only.
The selection is highlighted through colors. The viewport highlighted with a
black outline.
- 8.8 Provide a mechanism for
highlighting and identifying active elements. [Priority 2]
- Note: On most systems, the focus is
used to identify and highlight active elements.
-
- Operasoft Opera 3.60 for MS-Windows allows for controlling link styles. No
information about support for event handlers.
- 8.9 Allow configuration so the user is
prompted to confirm any form submission not caused by explicit user request to
activate a form submit control. [Priority 2]
- Note: For example, do not submit a form
automatically when a menu option is selected, when all fields of a form have
been filled out, or when a mouseover event occurs. The user agent may satisfy
this checkpoint by prompting the user to confirm all form
submissions.
-
- No information available.
- 8.10 Indicate the relative position of
the viewport in rendered content (e.g., the proportion of an audio or video
clip that has been played, the proportion of a Web page that has been viewed,
etc.). [Priority 3]
- Note: The user agent may calculate the
relative position according to content focus position, selection position, or
viewport position, depending on how the user has been browsing. The user agent
may indicate the proportion of content viewed in a number of ways, including as
a percentage, as a relative size in bytes, etc. For two-dimensional renderings,
relative position includes both vertical and horizontal positions.
-
- Microsoft Internet Explorer 5.0 for MS-Windows
- Netscape Navigator 4.x for MS-Windows
- Operasoft Opera 3.60 for MS-Windows
- RealPlayer G2
- The Real Player 7 (Version 6.0.7.362) status bar shows elapsed time and
total clip time.
- Microsoft Media Player
- Amaya, graphically.
Checkpoints for user interface accessibility:
-
9.1 Provide information to the user about current user preferences
for input configurations (e.g., keyboard or voice bindings).
[Priority 1]
-
- Microsoft Word for Windows 97 (not a WWW browser, but demonstrates
concept).
- Amaya does this the "brute force" way since attribute values are available
to the user.
-
9.2 Avoid default input configurations that interfere with operating
system accessibility conventions. [Priority 1]
- Note: In particular, default
configurations should not interfere with operating conventions for keyboard
accessibility. Information about operating system accessibility conventions is
available in the Techniques document [UAAG10-TECHS]. Refer also to checkpoint
5.8.
-
- Microsoft Internet Explorer 5.0 for MS-Windows
- Netscape Navigator 4.x for MS-Windows
- Operasoft Opera 3.60 for MS-Windows
-
9.3 Provide information to the user about current author-specified
input configurations (e.g., keyboard bindings specified in HTML documents with
the "accesskey" attribute). [Priority 2]
-
- Amaya does this the brute force way by providing information about
attribute values.
- 9.4 Allow the user to change the default
input configuration as follows: Allow the user to override any binding that is
part of the user agent default input configuration (checkpoint 9.8). The user
agent is not required to allow the user to override standard bindings for the
operating system (e.g., for access to help). For any binding in the default
keyboard configuration, allow the user to override it with a binding of a
single key alone or with modifier keys. [Priority 2]
- Note: This checkpoint applies to all
supported input methods: keyboard, voice, graphical user interface, etc. The
override requirement only applies to bindings for the same input method (i.e.,
the user must be able to override a keyboard binding with another keyboard
binding). Refer also to
checkpoint 9.5,
checkpoint 9.9,
checkpoint 9.8, and
checkpoint 10.3.
-
- pwWebSpeak 3.0: Mappings are defined in a profile (e.g., to bind F1 to open
the open page dialog). Users can change mappings for functionalities, but only
before launching the program.
- 9.5 Allow the user to assign a
single-key binding to at least a majority of the functionalities available in
the default keyboard configuration (refer to checkpoint 9.8).
[Priority 2]
- Note: In some modes of interaction
(e.g., when the user is entering text), the number of available single keys
will be significantly reduced. The number of available single keys will also be
determined by the keyboard device capabilities. This checkpoint is an important
special case of checkpoint
9.4. Refer also to
checkpoint 1.3,
checkpoint 9.9,
checkpoint 9.8, and
checkpoint 10.3.
-
- Jaws 3.7 provides single-key access to speech-rate increase/decrease
- pwWebSpeak 3.0: Mappings are defined in a profile (e.g., to bind F1 to open
the open page dialog). Users can specify single key (ascii letter) mappings for
functionalities, but only before launching the program.
-
9.6 Follow operating system conventions to indicate the input
configuration. [Priority 2]
- Note: For example, on some operating systems, developers
may specify which command sequence will activate a functionality so that the
standard user interface components display that binding. For example, if a
functionality is available from a menu, the letter of the activating key will
be underlined in the menu. This checkpoint is an important special case of checkpoint 5.8.
-
- Microsoft Internet Explorer 5.0 for MS-Windows
- Netscape Navigator 4.x for MS-Windows
- Operasoft Opera 3.60 for MS-Windows
- 9.7 For the configuration requirements of
this document, allow the user to save user preferences in at least one user
profile. Allow users to select from among available profiles or no profile
(i.e., the user agent default settings). [Priority 2]
- Note: The configuration requirements of
the checkpoints in this document involve user preferences for styles,
presentation rates, input configurations, navigation, viewport behavior, and
user agent alerts.
-
- Microsoft Internet Explorer 5.0 for MS-Windows does, for information that
can be contained in user style sheets.
- Operasoft Opera 3.60 for MS-Windows does, for information that can be
contained in user style sheets.
- NN 4.61 for Linux: Yes, since configuration is done through XResources,
users can specify their own resources.
- Amaya
offers profiles
- 9.8
Ensure that the default input configuration includes bindings for the following
functionalities required by other checkpoints in this document: move focus to
next active element; move focus to previous active element; activate focused
link; search for text; search again for same text; next history state
(forward); previous history state (back); increase size of rendered text;
decrease size of rendered text; increase global volume; decrease global volume;
(each of) stop, pause, resume, fast advance, and fast reverse selected audio,
video, and animation. If the user agent supports the following functionalities,
the default input configuration must also include bindings for them: enter URI
for new resource; add to favorites (i.e., bookmarked resources); view
favorites; stop loading resource; reload resource; refresh rendering; forward
one viewport; back one viewport; next line; previous line.
[Priority 2]
-
- Microsoft Internet Explorer 5.0 for MS-Windows
- Operasoft Opera 3.60 for MS-Windows
- 9.9 For graphical user interfaces,
allow the user to configure the position of controls on tool bars of the user
agent user interface, to select or remove controls for the user interface from
a predefined set, and to restore the default user interface.
[Priority 3]
- Note: This checkpoint is an important special case of checkpoint 9.4.
-
- NN 4.51 for Linux: Yes. It's possible to:
- View the toolbar a certain way (refer to Preferences/Appearance)
- Control the position of the tool bar
- Add menus to the tool bar
- Control text of menus and existence of menus in the defaults file. E.g.,
"*Composition*toggleNavigationToolbar.mnemonic: T"
Checkpoints for accessible documentation:
- 10.1 Ensure that at least one version of
the product documentation conforms to at least Level Double-A of the Web
Content Accessibility Guidelines 1.0 [WCAG10]. [Priority 1]
-
May require developer documentation
-
10.2 Document all user agent features that promote accessibility.
[Priority 1]
- Note: For example, review the
documentation or help system to ensure that it includes information about the
accessibility requirements of
WAI Guidelines.
-
May require developer documentation
-
10.3 Document the default input configuration (e.g., default
keyboard bindings). [Priority 1]
-
May require developer documentation
- Microsoft Internet Explorer 5.0 for MS-Windows
- Operasoft Opera 3.60 for MS-Windows
- Lynx for UNIX
- pwWebSpeak
- NN 4.61 for Linux: The default bindings are listed in the default
configuration file.
-
10.4 In a dedicated section of the documentation, describe all
features of the user agent that promote accessibility. [Priority 2]
- Note: This is a more specific
requirement than
checkpoint 10.2.
-
May require developer documentation
- 10.5 In each software release, document
all changes that affect accessibility. [Priority 2]
- Note: Features that affect accessibility are listed in
this document and in platform-specific accessibility guidelines.
-
- Real Player 7 (Version 6.0.7.362) includes a section called "What's New"
which reviews new features and changes to the interface.
-
Active element
- An active element is an element with behaviors that may be
activated (or
"triggered") either through the user interface or through an
API (e.g., by using scripts). Some
element instances may be active at times but not at others (e.g., they may be
"deactivated" through scripts, or they may only be active for a period of time
determined by the author). Which elements are active depends on the document
language and whether the features are supported by the user agent. In
HTML 4
[HTML4] documents, for example, active elements include links, image
maps, form controls, element instances with a value for the "longdesc"
attribute, and element instances with scripts (event handlers) explicitly
associated with them (e.g., through the various "on" attributes). Most systems
use the content focus to navigate active elements and identify which is to be
activated. An active element's behavior may be triggered through any number of
mechanisms, including the mouse, keyboard, an API, etc. The effect of activation depends on
the element. For instance, when a link is activated, the user agent generally
retrieves the linked Web
resource. When a form control is activated, it may change state
(e.g., check boxes) or may take user input (e.g., a text entry field). Refer
also to the definition of event
handler.
-
Alert
- In this document, "to alert" means to make the user aware
of some event, without requiring acknowledgement. For example, the user agent
may alert the user that new content is available on the server by displaying a
text message in the user agent's status bar.
Refer to checkpoint 1.5 for
requirements about alerts.
- Application
Programming Interface (API), standard input/output/device
API
- An application programming interface (API) defines how
communication may take place between applications.
As part of encouraging interoperability, this document recommends using
standard APIs where possible, although this document does
not define in all cases how those APIs are standardized (i.e., whether they are
defined by specifications such as W3C Recommendations, defined by an operating
system vendor, de facto standards, etc.). Implementing
APIs that are independent of a particular operating system (e.g., the W3C DOM
Level 2 specifications) may reduce implementation costs for multi-platform user
agents and promote the development of multi-platform assistive technologies.
Implementing standard APIs defined for a particular operating system may reduce
implementation costs for assistive technology developers who wish to
interoperate with more than one piece of software running on that operating
system.
A "device API" defines how communication may take place
with an input or output device such as a keyboard, mouse, video card, etc. A
"standard device API" is one that is considered standard for that particular
device on a given operating or windowing system.
In this document, an "input/output API" defines how
applications or devices communicate with a user agent. As used in this
document, input and output APIs include, but are not limited to, device APIs.
Input and output APIs also include more abstract communication interfaces than
those specified by device APIs. A "standard input/output API" is one that is
expected to be implemented by software running on a particular operating
system. Standard input/output APIs may vary from system to system. For example,
on desktop computers today, the standard input APIs are for
the mouse and keyboard. For touch screen devices or mobile devices, standard
input APIs may include stylus, buttons, voice, etc. The
graphical display and sound card are considered standard ouput devices for a
graphical desktop computer environment, and each has a standard
API.
- Assistive technology
- In the context of this document, an assistive technology
is a
user agent that:
- relies on services (such as retrieving
Web resources, parsing markup, etc.) provided by one or more other
"host" user agents. Assistive technologies communicate data and messages with
host user agents by using and monitoring APIs.
- provides services beyond those offered by the host user agents to meet the
requirements of a users with disabilities. Additional services include
alternative renderings (e.g., as synthesized speech or magnified content),
alternative input methods (e.g., voice), additional navigation or orientation
mechanisms, content transformations (e.g., to make tables more accessible),
etc.
For example, screen reader software is an assistive technology because it
relies on browsers or other software to enable Web access, particularly for
people with visual and learning disabilities.
Examples of assistive technologies that are important in the context of this
document include the following:
- screen magnifiers, which are used by people with visual disabilities to
enlarge and change colors on the screen to improve the visual readability of
rendered text and images.
- screen readers, which are used by people who are blind or have reading
disabilities to read textual information through synthesized speech or braille
displays.
- speech recognition software, which may be used by people who have some
physical disabilities.
- alternative keyboards, which are used by people with certain physical
disabilities to simulate the keyboard.
- alternative pointing devices, which are used by people with certain
physical disabilities to simulate mouse pointing and button activations.
- Beyond this document, assistive technologies consist of
software or hardware that has been specifically designed to assist people with
disabilities in carrying out daily activities, e.g., wheelchairs, reading
machines, devices for grasping, text telephones, vibrating pagers, etc.
-
Attribute
- This document uses the term "attribute" in the XML sense:
an element may have a set of attribute specifications (refer to the XML 1.0
specification
[XML] section 3).
-
Audio, Audio object
- An audio object is content rendered as sound through an
audio
viewport.
- Audio-only
presentation
- An audio-only presentation is a
presentation consisting exclusively of
one or more audio
tracks presented concurrently or in series. Examples of an
audio-only presentation include a musical performance, a radio-style news
broadcast, and a book reading.
-
Audio track
- An audio track is an audio object that is intended as a whole or
partial
presentation. An audio track may, but is not required to, correspond
to a single audio channel (left or right audio channel).
- Auditory description
- An auditory description is either a prerecorded human
voice or a synthesized voice (recorded or generated dynamically) describing the
key visual elements of a movie or animation. The auditory description is synchronized with the audio track of the presentation, usually during
natural pauses in the audio
track. Auditory descriptions include information about actions, body
language, graphics, and scene changes.
-
Author styles
- Authors styles are style property values that come from a
document, or from its associated style sheets, or that are generated by the
server.
-
Captions
- Captions (sometimes called "closed captions") are text
transcripts that are
synchronized with other audio or visual tracks. Captions convey
information about spoken words and non-spoken sounds such as sound effects.
They benefit people who are deaf or hard-of-hearing, and anyone who cannot hear
the audio (e.g., someone in a noisy environment). Captions are generally
rendered
graphically above, below, or superimposed over video.
Note: Other terms that include the word "caption" may have different
meanings in this document. For instance, a "table caption" is a title for the
table, often positioned graphically above or below the table. In this document,
the intended meaning of "caption" will be clear from context.
- Collated text
transcript
- A collated text transcript is a text equivalent of a movie or animation. More
specifically, it is the combination of the text transcript of the audio track and the text equivalent of the
visual track. For example, a collated text transcript typically includes
segments of spoken dialogue interspersed with text descriptions of the key
visual elements of a presentation (actions, body language, graphics, and scene
changes). Refer also to the definitions of text transcript and auditory
description. Collated text transcripts are essential for individuals
who are deaf-blind.
-
Configure and
Control
- In the context of this document, the verbs "to control"
and "to configure" share in common the idea of governance such as a user may
exercise over interface layout, user agent behavior, rendering style, and other
parameters required by this document. Generally, the difference in the terms
centers on the idea of persistence. When a user makes a change by
"controlling" a setting, that change usually does not persist beyond that user
session. On the other hand, when a user "configures" a setting, that setting
typically persists into later user sessions. Furthermore, the term "control"
typically means that the change can be made easily (such as through a keyboard
shortcut) and that the results of the change occur immediately, whereas the
term "configure" typically means that making the change requires more time and
effort (such as making the change via a series of menus leading to a dialog
box, via style sheets or scripts, etc.) and that the results of the change may
not take effect immediately (e.g., due to time spent reinitializing the system,
initiating a new session, rebooting the system). In order to be able to
configure and control the user agent, the user must be able to "read" as well
as "write" values for these parameters. Configuration settings may be stored in
a profile. The range and granularity of the
changes that can be controlled or configured by the user may depend on system
or hardware limitations.
Both configuration and control may apply at different "levels": across
Web resources (i.e., at the user agent
level, or inherited from the system), to the entirety of a Web resource, or to
components of a Web resource (e.g., on a per-element basis). For example, users
may configure the user agent to apply the same font family across Web
resources, so that all text is
displayed by default using that font family. Or, the user may wish to configure
the rendering of a particular element type, which may be done through style
sheets. Or, the user may wish to control the text size dynamically (zooming in
and out) for a given document, without having to reconfigure the user agent.
Or, the user may wish to control the text size dynamically for a given element,
e.g., by navigating to the element and zooming in on it.
Note: In this document, the noun "control" means "user
interface component" or "form component".
-
Content
- In this specification, the noun "content" is used in three
ways:
- It is used to mean the document
object as a whole or in parts.
- It is used to mean the content of an HTML or XML element, in the sense
employed by the XML 1.0 specification ([XML], section 3.1): "The text between
the start-tag and end-tag is called the element's content." Context should
indicate that the term content is being used in this sense.
- It is used in the context of the phrases non-text content and
text content.
-
Device-independence
- Device-independence refers to the ability to make use of
software with any supported input or output device.
-
Document Object,
Document Object Model
- In general usage, the term "document object" refers to the user agent's
representation of data (e.g., a document). This data generally comes from the
document
source, but may also be generated (from style sheets, scripts,
transformations, etc.), produced as a result of preferences set within the user
agent, added as the result of a repair performed automatically by the user
agent, etc. Some data that is part of the document object is routinely
rendered (e.g., in HTML, what appears between the start and end tags
of elements and the values of attributes such as "alt", "title", and
"summary"). Other parts of the document object are generally processed by the
user agent without user awareness, such as DTD-defined names of element types
and attributes, and other attribute values such as "href", "id", etc. These
guidelines require that users have access to both types of data through the
user interface.
A "document object model" is the abstraction that governs the construction
of the user agent's document object. The document object model employed by
different user agents may vary in implementation and sometimes in scope. This
specification requires that user agents implement the
APIs defined in the "Document Object
Model (DOM) Level 2 Specification" ([DOM2CORE], [DOM2HTML],
[DOM2STYLE]) for access to HTML,
XML, and CSS content. These DOM APIs allow authors
to access and modify the content via a scripting language (e.g., JavaScript) in
a consistent manner across different scripting languages. As a standard
interface, the DOM APIs make it easier not just for authors, but for assistive
technology developers to extract information and render it in ways most suited
to the needs of particular users. The relevant W3C DOM Recommendations are
listed in the references.
-
Document source, Document source view
- In this document, the term "document source" refers to the
data that the user agent receives as the direct result of a request for a
Web resource (e.g., as the result of an
HTTP/1.1
[RFC2616] "GET", as the result of opening a local resource, etc.). A
"document source view" generally renders the document source as text written in
the markup language(s) used to build it. The document source is generally a
subset of the document
object (e.g., since the document object may include
repair content).
-
Documentation
- Documentation refers to all information
provided by the vendor about a product, including all product manuals,
installation instructions, the help system, and tutorials.
-
Element
- This document uses the term "element" both in the XML
sense (an element is a syntactic construct as described in the XML 1.0
specification
[XML], section 3) and more generally to mean a type of content (such
as video or sound) or a logical construct (such as a header or list).
-
Equivalent (for content)
- In the context of this document, an equivalency
relationship between two pieces of content
means that one piece -- the "equivalent" -- is able to serve essentially the
same function for a person with a disability (at least insofar as is feasible,
given the nature of the disability and the state of technology) as the other
piece -- the "equivalency target" -- does
for a person without any disability. For example, the text "The Full Moon"
might convey the same information as an image of a full moon when presented to
users. If the image is part of a link and understanding the image is crucial to
guessing the link target, then the equivalent must also give users an idea of
the link target. Thus, an equivalent is provided to fulfill the same function
as the equivalency target.
Equivalents include text
equivalents (e.g., text equivalents for images; text transcripts for
audio tracks; collated text transcripts for multimedia presentations and
animations) and non-text
equivalents (e.g., a prerecorded auditory description of a visual
track of a movie, or a sign language video rendition of a written text, etc.).
Please refer to the definitions of text
content and non-text
content for more information.
- Each markup language defines its own mechanisms for
specifying equivalents. For instance, in HTML 4 [HTML4] or SMIL 1.0 [SMIL], authors may
use the "alt" attribute to specify a text equivalent for some elements. In HTML
4, authors may provide equivalents (or portions of equivalents) in attribute
values (e.g., the "summary" attribute for the TABLE element), in element
content (e.g., OBJECT for external content it specifies, NOFRAMES for frame
equivalents, and NOSCRIPT for script equivalents), and in prose. Please consult
the Web Content Accessibility Guidelines 1.0 [WCAG10] and its associated
Techniques document [WCAG10-TECHS] for more
information about equivalents.
- Events and
scripting, event handler
- User agents often perform a task when an event occurs that
is due to user interaction (e.g., document loading, mouse motion or a key
press), a request from the operating system, etc. Some markup languages allow
authors to specify that a script, called an event handler, be executed when
the event occurs. Note: The combination of HTML, style sheets,
the Document Object Model (DOM) and scripting is commonly
referred to as "Dynamic HTML" or DHTML. However, as there is no W3C
specification that formally defines DHTML, this document only refers to event
handlers and scripts.
-
Explicit user request
- In several checkpoints in this document, the term "explicit user request"
is used to mean any user interaction
recognized with certainty to be for a specific purpose. For
instance, when the user selects "New viewport" in the user agent's user
interface, this is an explicit user request for a new viewport. On the other
hand, it is not an explicit request when the user activates a link and that
link has been marked up by the author to open a new viewport (since the user
may not know that a new viewport will open). Nor is it an explicit user request
even if the link text states "will open a new viewport". Some other examples of
explicit user requests include "yes" responses to prompts from the user agent,
configuration through the user agent's user interface, activation of known form
submit controls, and link activation (which should not be assumed to mean more
than "get this linked resource", even if the link text or title or role
indicates more). Some examples of behaviors that happen without explicit user
request include changes due to scripts. Note: Users make
mistakes. For example, a user may submit a form inadvertently by activating a
known form submit control. In this document, this type of mistake is still
considered an explicit user request.
-
Focus,
content focus,
user interface focus, current focus
- The notion of focus refers to two identifying mechanisms
of user agents:
- The "content focus" designates an
active element in a document (e.g., a link or radio button). A
viewport has at most one content focus.
- The "user interface focus" designates a control of the user interface that
will respond to user input (e.g., a radio button, text box, menu, etc.).
In this document, the term "focus" by itself encompasses both types of focus.
Where one is meant specifically in this document, it is identified.
When several viewports coexist, each may have a content and user interface
focus. At all times, only one content focus or one user
interface focus is active, called the current focus. The current focus responds
to user input and may be toggled between content focus and user interface focus
through the keyboard, pointing device, etc. Both the content and user interface
focus may be
highlighted. Refer also to the definition of point of regard.
-
Graphical
- In this document, the term "graphical" refers to
information (text, colors, graphics, images, animations, etc.) rendered for
visual consumption.
-
Highlight
- In this document, "to highlight" means to emphasize
through the user interface. For example, user agents highlight which content is
selected or focused and which viewport is the current viewport. Graphical
highlight mechanisms include dotted boxes, underlining, and reverse video.
Synthesized speech highlight mechanisms include alterations of voice pitch and
volume.
- Input configuration
- An input configuration is the mapping of user agent
functionalities to some user
interface trigger mechanisms (e.g., menus, buttons, keyboard keys,
voice commands, etc.). The default input configuration is the mapping the user
finds after installation of the software; it must be part of the user agent
documentation (per checkpoint 10.3]).
-
Multimedia Presentation
- For the purposes of this document, a multimedia
presentation is a
presentation that is not a visual-only presentation,
audio-only presentation, or tactile-only presentation. In a "classic"
multimedia presentation (e.g., a movie that has sound track or an animation
with accompanying audio), at least one
visual track is closely
synchronized with at least one
audio track.
-
Natural language
- Natural language is spoken, written, or signed human
language such as French, Japanese, and American Sign Language. On the Web, the
natural language of content may
be specified by markup or HTTP headers. Some examples include the
"lang" attribute in HTML 4 ([HTML4] section 8.1), the "xml:lang"
attribute in XML 1.0 ([XML], section 2.12), the
HTML 4 "hreflang" attribute for links in HTML 4
([HTML4],
section 12.1.5), the HTTP Content-Language header ([RFC2616], section 14.12) and the
Accept-Language request header ([RFC2616], section 14.4).
-
Point of regard
- The point of regard is a position in rendered
content that the user is presumed to be viewing. The dimensions of
the point of regard may vary. For example, it may be a point (e.g., a moment in
an audio rendering or a cursor in a graphical rendering), or a range of text
(e.g., focused text), or a two-dimensional area (e.g., content rendered through
a two-dimensional graphical viewport). The point of regard is almost always
within a viewport (though the dimensions of the point of regard could exceed
those of the viewport). The point of regard may also refer to a particular
moment in time for content that changes over time (e.g., an
audio-only presentation). User agents may use the focus,
selection, or other means to designate the point of regard. A user
agent should not change the point of regard unexpectedly as this may disorient
the user.
-
Presentation
- In this document, the term presentation refers to a
collection of information, consisting of one or more
Web resources, intended to be rendered
simultaneously, and identified by a single URI. In general, a presentation has
an inherent time component (i.e., it's not just a static "Web page" (refer to
the definition of "Web page" in "Web Characterization Terminology and
Definitions Sheet" [WEBCHAR]).
-
Profile
- A profile is a named and persistent representation of user preferences that
may be used to configure a user agent. Preferences include input
configurations, style preferences, etc. On systems with distinct user accounts,
profiles enable users to reconfigure software quickly when they log on, and
profiles may be shared by several users. Platform-independent profiles are
useful for those who use the same user agent on different platforms.
-
Prompt
- In this document, "to prompt" means to require input from
the user. The user agent should allow users to
configure how they wish to be prompted. For instance, for a user
agent functionality X, configurations might include: always do X without
prompting me, never do X without prompting me, don't ever do X but tell me when
you could have done X but didn't, don't ever do X and don't tell me, etc.
- Properties, values, and
defaults
- A user agent renders a document by applying formatting
algorithms and style information to the document's elements. Formatting depends
on a number of factors, including where the document is rendered: on screen, on
paper, through loudspeakers, on a braille display, on a mobile device, etc.
Style information (e.g., fonts, colors, voice inflection, etc.) may come from
the elements themselves (e.g., certain font and phrase elements in HTML), from
style sheets, or from user agent settings. For the purposes of these
guidelines, each formatting or style option is governed by a property and each
property may take one value from a set of legal values. Generally in this
document, the term "property"
has the meaning defined in CSS 2 ([CSS2], section 3). A reference to
"styles" in this document means a set of style-related properties.
- The value given to a property by a user agent when it is
installed is called the property's default value.
-
Recognize
- A user agent is said to recognize a piece of information
when the user agent developer has designed it to handle that information. A
user agent recognizes those features of markup or style languages that it
implements and the behavior of the user interface controls that it provides.
User agents may not understand everything the author has encoded in content,
such as the semantics of XML elements unknown to the user agent, whether the
link text and link title accurately describe the linked resource, whether a
sentence (that has not been specially marked up) is a text equivalent for an
image, or whether a script is calculating a factorial. A user agent does not
recognize everything that a script does, even though it may implement the scripting language. However, it
will recognize some information encoded in scripts, such as code to open a
viewport or retrieve a resource from the Web. The Techniques document
[UAAG10-TECHS] lists some markup known to affect accessibility that
should be recognized by user agents.
-
Rendered content
- The rendered content is the part of
content rendered in a given viewport (whether visual, auditory, or
tactile).
-
Repair content, repair text
- In this document, the term "repair content" refers to
content generated by the user agent in order to correct an error condition or
as the result of a user preference. "Repair text" means repair content
consisting only of text. This
document does not require user agents to include repair content in the document
object.
Some error conditions that may lead to the generation of repair content
include:
- Erroneous or incomplete content (e.g., ill-formed markup, invalid markup,
missing text
equivalents, etc.);
- Missing resources for handling or rendering content (e.g., the user agent
lacks a font family to display some characters, the user agent doesn't
implement a particular scripting language, etc.);
Some user preferences may change content, such as when the user has turned
off support for images and a placeholder icon appears in place of each image
that has not been loaded.
For more information about repair techniques for Web content and software,
refer to "Techniques For Accessibility Evaluation And Repair Tools" [AERT].
- Selection, current
selection
- The selection generally identifies a range of content
(e.g., text, images, etc.) in a document. The
selection may be structured (based on the document tree) or
unstructured (e.g., text-based). Content may be selected through user
interaction, scripts, etc. The selection may be used for a variety of purposes:
for cut and paste operations, to designate a specific element in a document, to
identify what a screen reader should read, etc.
The selection may be set by the user (e.g., by a pointing device or the
keyboard) or through an application programming interface (API). A viewport has
at most one selection (though the selection may be rendered graphically as discontinuous text fragments).
When several viewports coexist, each may have a selection, but only one is
active, called the current selection.
On the screen, the selection may be
highlighted using colors, fonts, graphics, magnification, etc. The
selection may also be rendered as inflected speech, for example.
- Support, implement, conform
- In this document, the terms "support", "implement", and
"conform" all refer to what a developer has designed a user agent to do, but
they represent different degrees of specificity. A user agent "supports"
general classes of objects, such as "images" or "Japanese". A user agent
"implements" a specification (e.g., the PNG and SVG image format
specifications, a particular scripting language, etc.) or an
API (e.g., the DOM API) when it has been
programmed to follow all or part of a specification. A user agent "conforms to"
a specification when it implements the specification and satisfies its
conformance criteria. This document includes some explicit conformance
requirements (e.g., to a particular level of the "Web Content Accessibility
Guidelines 1.0"
[WCAG10]).
- Synchronize
- In this document, "to synchronize" refers to the
time-coordination of two or more presentation components (e.g., in a multimedia
presentation, a visual track with captions). For Web content developers, the
requirement to synchronize means to provide the data that will permit sensible
time-coordinated rendering by a user agent. For example, Web content developers
can ensure that the segments of caption text are neither too long nor too
short, and that they map to segments of the visual track that are appropriate
in length. For user agent developers, the requirement to synchronize means to
present the content in a sensible time-coordinated fashion under a wide range
of circumstances including technology constraints (e.g., small text-only
displays), user limitations (slow reading speeds, large font sizes, high need
for review or repeat functions), and content that is sub-optimal in terms of
accessibility.
-
Tactile object
- A tactile object is output from a tactile viewport. Tactile objects include text (rendered as braille) and graphics
(rendered as raised-line drawings).
- Tactile-only
presentation
- A tactile-only presentation is a
presentation consisting exclusively of
one or more tactile
tracks presented concurrently or in series.
-
Tactile track
- A tactile track is a
tactile object that is intended as a whole or partial
presentation. This does not necessarily
correspond to a single physical or logical track on the storage or delivery
media.
-
Text
- In this document, the term "text" used by itself refers to
a sequence of characters from a markup language's document character set (e.g.,
Unicode or ISO 10646). Refer to the "Character Model for the World Wide Web "
[CHARMOD] for more information about text and characters.
Note: This document makes use of other terms that include the word
"text" that have highly specialized meanings:
collated text transcript, non-text content,
text content, non-text
element, text
element, text
equivalent, and text
transcript.
-
Text content, non-text content, text
element, non-text element, text equivalent, non-text
equivalent
- In this document, the term "text element" means content that, when rendered, is understandable
in each of three modes to three reference groups:
- visually-displayed text, for users who are deaf and adept in reading
visually-displayed text;
- synthesized speech, for users who are blind and adept in use of synthesized
speech;
- braille, for users who are deaf-blind and adept at reading braille.
In these definitions, a text element is said to be "understandable" when it
fulfills its communication function to representatives of the three reference
groups. Furthermore, these definitions make assumptions such as the
availability of appropriate hardware and software, that content represents a
general mix of purposes (information, education, entertainment, commerce), that
the individuals in the groups are able to understand the natural language of
the content, that the individuals in the groups are not required to have
specialized skills (e.g., computer science degree), etc.
A text element may contain markup for style (e.g., font size or color),
structure (e.g., heading levels), and other semantics. However, the essential
function of the text element should be retained even if style information
happens to be lost in rendering. In this document, the term "text content"
refers to content that is composed of one or more text elements. A "non-text
element" is an element that fails to be understandable when rendered
in any of three modes to their respective reference disability
audiences. Thus, text elements have essential accessibility advantages often
associated with
text while non-text elements are those
that lack one or more such advantages.
In this document, the term "non-text content" refers to content that is
composed of one or more non-text elements. Per checkpoint 1.1 of "Web Content
Accessibility Guidelines 1.0" [WCAG10], authors must provide a
text equivalent for every author-supplied non-text element. Similarly, user
agent developers must provide a text equivalent for every non-text element
offered by the user agent to the user (refer to checkpoint 1.5).
Note that the terms "text element" and "non-text element" are defined by the
characteristics of their output (e.g., rendering) rather than those of their
input (e.g., information sources) or their internals (e.g., format). For
example, in principle, a text element can be generated or encoded in any
fashion as long as it has the proper output characteristics. In general, text
elements are composed of text (i.e., a
sequence of characters). Both text elements and non-text elements should be
understood as "pre-rendering" content in contrast to the "post-rendering"
content that they produce.
A "text equivalent" is a text element that, when rendered, serves
essentially the same function as some other content (i.e., an equivalency
target) does for a person without any disability. Similarly, a
"non-text equivalent" is a non-text element that, when rendered, serves
essentially the same function as the equivalency target does for a person
without any disability. Please refer also to the definition of
equivalent.
-
Text transcript
- A text transcript is a text equivalent of audio
information (e.g., an
audio-only presentation or the
audio track of a movie or animation). It provides text for both
spoken words and non-spoken sounds such as sound effects. Text transcripts make
audio information accessible to people who have hearing disabilities and to
people who cannot play the audio. Text transcripts are usually pre-written but
may be generated on the fly (e.g., by speech-to-text converters). Refer also to
the definitions of captions
and
collated text transcripts.
- User
agent
- In this document, the term "user agent" is used in two
ways:
- Any software that retrieves and renders Web content for users. This may
include Web browsers, media players, plug-ins, and other programs -- including
assistive
technologies -- that help in retrieving and rendering Web
content.
- The subject of a conformance claim to "User Agent Accessibility Guidelines
1.0"
[UAAG10]. This is the most common use of the term in this document
and is the usage in the checkpoints.
-
User agent default styles
- User agent default styles are style property values applied in the absence of
any author or user styles. Some markup languages specify a default rendering
for documents in that markup language. Other specifications may not specify
default styles. For example, XML 1.0 [XML] does not specify
default styles for XML documents. HTML 4 [HTML4] does not
specify default styles for HTML documents, but the CSS 2 [CSS2] specification
suggests a
sample default style sheet for HTML 4 based on current practice.
-
User interface
- For the purposes of this document, user interface includes
both:
- the "user agent user
interface", i.e., the controls and mechanisms offered by the user
agent for user interaction, such as menus, buttons, keyboard access, etc.
- the "content user interface", i.e., the
active elements that are part of content, such as form controls,
links, applets, etc.
The document distinguishes them only where required for clarity.
-
User styles
- User styles are style property values that come from user
interface settings, user style sheets, or other user interactions.
-
Visual object
- A visual object is output from a visual viewport. Visual objects include graphics,
text, and visual portions of movies and animations.
- Visual-only
presentation
- A visual-only presentation is a
presentation consisting exclusively of
one or more visual
tracks presented concurrently or in series.
-
Visual track
- A visual track is a
visual object that is intended as a whole or partial
presentation. A visual track does not
necessarily correspond to a single physical or software object. A visual track
can be text-based or graphic, static or animated.
- Views,
viewports, and current viewport
- User agents may handle different types of content: markup language, sound, video, etc.
The user views rendered
content through a
viewport, which may be a window, a frame, a piece of paper, a
loudspeaker, a virtual magnifying glass, etc. A viewport may contain another
viewport (e.g., nested frames). Viewports do not include user interface
controls such as prompts, menus, alerts, etc.
The viewport that contains both the
current focus and the current selection is called the current
viewport. The current viewport is generally highlighted when several viewports coexist. A
user agent must provide mechanisms for accessing all content that can be
presented by each viewport (e.g., scrolling mechanisms, advance and rewind,
etc.).
- User agents may render the same content in a variety of
ways; each rendering is called a
view. For instance, a user agent may allow users to view an
entire document or just a list of the document's headers. These are two
different views of the document.
-
Web resource
- The term "Web resource" is used in this document in
accordance with Web Characterization Terminology and Definitions Sheet [WEBCHAR] to
mean anything that can be identified by a Uniform Resource Identifier
(URI) as defined in RFC 2396 [RFC2396].
For the latest version of any W3C specification please
consult the list of W3C Technical Reports at
http://www.w3.org/TR. Some documents listed below may have been superseded
since the publication of this document.
- [AERT]
- "Techniques For
Accessibility Evaluation And Repair Tools", C. Ridpath, W. Chisholm,
eds., 26 April 2000. This W3C Working Draft is
http://www.w3.org/TR/2000/WD-AERT-20000426.
- [CHARMOD]
- "Character
Model for the World Wide Web", M. Dürst and F. Yergeau, eds.,
29 November 1999. This W3C Working Draft is
http://www.w3.org/TR/1999/WD-charmod-19991129/
- [CSS1]
- "CSS, level 1
Recommendation", B. Bos, H. Wium Lie, eds., 17 December 1996,
revised 11 January 1999. This W3C Recommendation is
http://www.w3.org/TR/1999/REC-CSS1-19990111.
- [CSS2]
- "CSS, level 2
Recommendation", B. Bos, H. Wium Lie, C. Lilley, and I. Jacobs,
eds., 12 May 1998. This W3C Recommendation is
http://www.w3.org/TR/1998/REC-CSS2-19980512.
- [DOM2CORE]
-
"Document Object Model (DOM) Level 2 Core Specification", M. Davis,
A. Le Hors, P. Le Hégaret, J. Robie, L. Wood, eds., 27 September 2000.
This W3C Proposed Recommendation is
http://www.w3.org/TR/2000/PR-DOM-Level-2-Core-20000927.
- [DOM2HTML]
-
"Document Object Model (DOM) Level 2 HTML Specification", A. Le
Hors, P. Le Hégaret, eds., 27 September 2000. This W3C Proposed
Recommendation is http://www.w3.org/TR/2000/PR-DOM-Level-2-HTML-20000927
- [DOM2STYLE]
-
"Document Object Model (DOM) Level 2 Style Specification", V.
Apparao, P. Le Hégaret, C. Wilson, eds., 27 September 2000. This W3C
Proposed Recommendation is
http://www.w3.org/TR/2000/PR-DOM-Level-2-Style-20000927.
- [HTML4]
- "HTML 4.01
Recommendation", D. Raggett, A. Le Hors, and I. Jacobs, eds., 24
December 1999. This W3C Recommendation is
http://www.w3.org/TR/1999/REC-html401-19991224.
- [MATHML]
- "Mathematical
Markup Language", P. Ion and R. Miner, eds., 7 April 1998. This W3C
Recommendation is http://www.w3.org/TR/1998/REC-MathML-19980407.
- [RFC2396]
- "Uniform Resource
Identifiers (URI): Generic Syntax", T. Berners-Lee, R. Fielding, L.
Masinter, August 1998.
- [RFC2616]
- "Hypertext Transfer
Protocol -- HTTP/1.1, J. Gettys, J. Mogul, H. Frystyk, L. Masinter,
P. Leach, T. Berners-Lee, June 1999.
- [SMIL]
- "Synchronized
Multimedia Integration Language (SMIL) 1.0 Specification", P.
Hoschka, ed., 15 June 1998. This W3C Recommendation is
http://www.w3.org/TR/1998/REC-smil-19980615.
- [SVG]
- "Scalable Vector
Graphics (SVG) 1.0 Specification", J. Ferraiolo, ed., 2 August 2000.
This W3C Candidate Recommendation is
http://www.w3.org/TR/2000/CR-SVG-20000802/.
- [UAAG10]
- "Implementation report
for User Agent Accessibility Guidelines 1.0", J. Gunderson, I.
Jacobs, eds. The latest draft of the guidelines is available at
http://www.w3.org/WAI/UA/UAAG10-IMP/.
-
[UAAG10-TECHS]
- "Techniques for User
Agent Accessibility Guidelines 1.0", J. Gunderson, I. Jacobs, eds.
The latest draft of the techniques document is available at
http://www.w3.org/TR/UAAG10-TECHS/.
- [WCAG10]
- "Web
Content Accessibility Guidelines 1.0", W. Chisholm, G. Vanderheiden,
and I. Jacobs, eds., 5 May 1999. This W3C Recommendation is
http://www.w3.org/TR/1999/WAI-WEBCONTENT-19990505.
-
[WCAG10-TECHS]
-
"Techniques for Web Content Accessibility Guidelines 1.0", W.
Chisholm, G. Vanderheiden, and I. Jacobs, eds. This W3C Note is
http://www.w3.org/TR/1999/WAI-WEBCONTENT-TECHS-19990505.
- [WEBCHAR]
- "Web
Characterization Terminology and Definitions Sheet", B. Lavoie, H.
F. Nielsen, eds., 24 May 1999. This is a W3C Working Draft that defines some
terms to establish a common understanding about key Web concepts. This W3C
Working Draft is http://www.w3.org/1999/05/WCA-terms/01.
- [XHTML10]
- "XHTML[tm]
1.0: The Extensible HyperText Markup Language", S. Pemberton, et
al., 26 January 2000. This W3C Recommendation is
http://www.w3.org/TR/2000/REC-xhtml1-20000126.
- [XML]
- "Extensible
Markup Language (XML) 1.0", T. Bray, J. Paoli, C.M.
Sperberg-McQueen, eds., 10 February 1998. This W3C Recommendation is
http://www.w3.org/TR/1998/REC-xml-19980210.
The active participants of the User Agent Accessibility Guidelines Working
Group who authored this document were: James Allan, Denis Anson (College
Misericordia), Kitch Barnicle, Harvey Bingham, Dick Brown (Microsoft), Al
Gilman, Jon Gunderson (Chair of the Working Group, University of Illinois,
Urbana-Champaign), Eric Hansen (Educational Testing Service), Ian Jacobs (Team
Contact, W3C), Marja-Riitta Koivunen, Tim Lacy (Microsoft), Charles
McCathieNevile (W3C), Mark Novak, David Poehlman, Mickey Quenzer (isSound),
Gregory Rosmaita (Visually Impaired Computer Users Group of New York City),
Madeleine Rothberg, and Rich Schwerdtfeger.
Many thanks to the following people who have contributed through review and
past participation in the Working Group: Paul Adelson, Olivier Borius, Judy
Brewer, Bryan Campbell, Kevin Carey, Tantek Çelik, Wendy Chisholm, David
Clark, Chetz Colwell, Wilson Craig, Nir Dagan, Daniel Dardailler, B. K. Delong,
Neal Ewers, Geoff Freed, John Gardner, Larry Goldberg, Glen Gordon, John
Grotting, Markku Hakkinen, Earle Harrison, Chris Hasser, Kathy Hewitt, Philipp
Hoschka, Masayasu Ishikawa, Phill Jenkins, Earl Johnson, Jan Kärrman (for
help with html2ps),
Leonard Kasday, George Kerscher, Peter Korn, Josh Krieger, Catherine Laws, Greg
Lowney, Susan Lesch, Scott Luebking, William Loughborough, Napoleon Maou, Peter
Meijer, Karen Moses, Masafumi Nakane, Charles Oppermann, Mike Paciello, David
Pawson, Michael Pederson, Helen Petrie, Michael Pieper, Jan Richards, Hans
Riesebos, Joe Roeder, Lakespur L. Roca, Lloyd Rutledge, Liam Quinn, T.V. Raman,
Robert Savellis, Constantine Stephanidis, Jim Thatcher, Jutta Treviranus, Claus
Thogersen, Steve Tyler, Gregg Vanderheiden, Jaap van Lelieveld, Jon S. von
Tetzchner, Willie Walker, Ben Weiss, Evan Wies, Chris Wilson, Henk Wittingen,
and Tom Wlodkowski.
Note: W3C does not guarantee the stability of any of
the following references outside of its control. These references are included
for convenience. References to products are not endorsements of those
products.
A list of alternative
Web browsers (assistive technologies and other user agents designed for
accessibility) is maintained at the WAI Web site.
- [DIRECTDOM]
- DirectDom technology, available from alphaWorks, allows a Java developer
to manipulate the live Document Object Model of a browser or Scalable Vector
Graphics plugin to build rich graphical user interfaces.