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Fwd: Re: Issues and comments arising from UA evaluations

From: Jon Gunderson <jongund@uiuc.edu>
Date: Wed, 13 Mar 2002 14:30:35 -0600
Message-Id: <>
To: w3c-wai-ua@w3.org

>Date: Wed, 13 Mar 2002 14:26:46 -0600
>To: "Ian B. Jacobs" <ij@w3.org>
>From: Jon Gunderson <jongund@uiuc.edu>
>Subject: Re: Issues and comments arising from UA evaluations
>Responses in JRG:
>At 03:26 PM 3/12/2002 -0500, you wrote:
>>Dear UAWG,
>>A number of issues about the UAAG 1.0 Candidate Recommendation
>>[1] have come up during recent reviews with developers. Most
>>of these issues only require clarification. However, there are a
>>couple of proposals for more substantial changes below that
>>I'd like to discuss at an upcoming teleconference.
>>Jon, I don't suggest that we add these to the issues list until
>>the UAWG has had a chance to discuss them.
>>Comments welcome,
>>  - Ian
>>[1] http://www.w3.org/TR/2001/CR-UAAG10-20010912/
>> From the Mozilla review:
>>  1) Can checkpoints 6.1 and 6.2 be satisfied if the
>>     APIs are not available out-of-process?
>>     Proposed: Yes.
>JRG: I agree, in or out of process access relates to Checkpoint 6.9
>> From the (incomplete) RealNetworks review:
>>  2) Add a section to the document explaining how other
>>     specifications can create profiles of UAAG 1.0
>>     conformance. For instance, if the FOO specification wants to
>>     require FOO user agents to conform to UAAG 1.0 in a
>>     particular manner, what should/must the FOO spec say?
>>     Proposed: I would like to write this up and send to the
>>     UAWG in the near future.
>JRG: I think this is good, but I think it would be good to work with 
>another working group trying to do this as part of the process.
>>  3) UAAG 1.0 needs to be clearer about the fact that a user
>>     agent is not required to satisfy all requirements for
>>     all implemented formats. I believe the document already
>>     says this, but it's not easy to find.
>JRG: Editorial
>>  4) Make clearer up front (e.g., at the beginning of section
>>     2, not just the conformance section) that a user agent
>>     can conform to fewer than all the checkpoints.
>JRG: Editorial
>> From the Opera review:
>>  5) Checkpoint 2.10 needs clarification. Current text:
>>     "Once the user has viewed the original author-supplied
>>     content associated with a placeholder, allow the user to turn
>>     off the rendering of the author-supplied content."
>>     Proposed:
>>     "If the user agent has satisfied checkpoint 2.3 by using
>>      a placeholder, then allow the user to toggle rendering
>>      between the placeholder and the original author-supplied
>>      content."
>JRG: Sounds good to me
>>  6) Checkpoint 3.1: Clarify that if the user agent allows the
>>     user to turn off all images, including background images,
>>     then this checkpoint is satisfied, but this is not
>>     the optimal solution (since better to be able to turn
>>     of background images separately).
>JRG: OK with me
>>  7) Clarify for 1.2, 9.5, 9.6 that checkpoint may be
>>     satisfied on a per event type basis; additional
>>     granularity (per handler) is not required. This
>>     clarification is consistent with our recent
>>     DOM discussions.
>JRG: I agree, we only want to trigger user interface events.  If more than 
>one event handler is associated with a user interface event, then all of 
>them should be triggered.
>>  8) Checkpoint 6.3: The title is "Programmatic
>>     access to non-HTML/XML content", but the first
>>     requirement refers to "markup language" (which would
>>     exclude, for example, images). Do we intend "all content"
>>     here, or just markup (non-HTML/XML) markup languages?
>JRG: I think we want the more general term, for example we want to include 
>things like PDF and FLASH.  FLASH is markup oriented, but I don't think PDF is.
>>     I don't have a proposal for this one.
>>  9) [Editorial] Clarify in 3.6 why P2 and 3.5 is P1.
>>     This is already in the techniques doc, so not critical.
>>10) Checkpoints 6.2 and 6.3 (DOM write access and
>>     programmatic access to other types of content):
>>     there is some content where it's a security issue
>>     to provide *any* kind of programmatic access. [Tantek
>>     made similar comments during the Mac IE review.]
>>     Some ideas for dealing with this:
>>     a) Provide programmatic access, but when security
>>     is an issue, prompt the user for confirmation
>>     (on configuration).
>>     b) If the user agent has a mechanism for allowing trusted
>>     programmatic access, then ATs should use this mechanism,
>>     and the UA must make available all content to these
>>     trusted agents.
>JRG: We have pretty limited write access requirement.  In forms it is 
>primarily to the value attribute with only the allowed values defined by 
>the author, since this is all any user gets to modify in the form.  We 
>don't allow the user to add nodes or change the type of control, becasue 
>the user does't.
>>11) Checkpoints 6.1/6.2: Is it a P1 to implement some API
>>     and P2 to implement the DOM 2 Core? See my additional
>>     thoughts below.
>JRG: I think we have put this one to rest many times, is there new 
>>12) Checkpoints 6.1-6.4: Perhaps it's better (though not
>>    necessarily simpler) to express these checkpoints as
>>    functional requirements. It may turn out that the
>>    functional requirements are met by implementing
>>    some piece of an API.
>JRG: Aren't they functional requirements now?
>> From the MAC IE review (not yet completed)
>>13) Checkpoint 2.2: "XML and SGML applications". According to Ian
>>   Hickson and Tantek Çelik (both there for the evaluation), one
>>   cannot reliably determine what's an xml and sgml application by
>>   sniffing content. We will need to be more precise about how one
>>   would determine that something is an xml or sgml application.
>>    I don't have a proposal for this one.
>>14) Checkpoint 3.4: Toggle scripts. Tantek argued that,
>>    since most pages include scripts, the following
>>    provision should not be P1:
>>       "In this configuration, provide an option to alert the
>>       user when executable content is available (but has not
>>       been executed)."
>>    The alert will be so frequent as to be ignored. One
>>    suggestion is to pull out this provision and make it a
>>    lower priority.
>>    Proposal: Make the alert a P3 requirement.
>>15) Checkpoint 6.2: Tantek stated that there are security
>>    issues for some types of programmatic access to content.
>>    (for instance, programmatic access to HTML's INPUT element,
>>    type="file", which might allow the author to upload a file
>>    from the user's computer without the user's permission).
>>    See my comments below on 6.1, 6.2, and 6.3.
>>16) Checkpoint 6.9: Timely access. The checkpoint reads:
>>     "Ensure that programmatic exchanges proceed in a timely
>>     manner." It's not clear which exchanges this checkpoint
>>     refers to - internal to the user agent? between the UA
>>     and ATs?
>>     Proposal: This refers to exchanges over the APIs required
>>     elsewhere in Guideline 6.
>>17) Checkpoint 7.4: Input configuration indications.
>>     Proposal: Clarify that the requirement is to "Follow
>>     operating environment *user interface* conventions to
>>     indicaxte the input configuration."
>>18) Checkpoints 7.3, 8.1:
>>     Proposal: Clarify that the expression "identified as such"
>>     means "identified as such in the specification". However,
>>     this does not account for W3C Notes such as "Accessibility
>>     features of CSS" which may be useful but not normative.
>>19) Checkpoint 9.3: Move content focus.
>>     Proposal: In point three, clarify that "each element" means
>>     each element in the set defined in point 1. Tantek
>>     recommended introducing the term "Focusable element" and
>>     using it in point 1.
>>20) Checkpoint 9.4: Restore history. The checkpoint reads:
>>      "For user agents that implement a viewport history
>>      mechanism, for each state in a viewport's browsing history,
>>      maintain information about the point of regard, content
>>      focus, and selection."
>>     However, even when a user agent implements a history
>>     mechanism, it may not keep all pages in its cache.
>>     Proposal: Do not require the user agent to restore state
>>     variables for pages removed from the history cache.
>>21) Checkpoint 9.7: The checkpoint title is "Move content focus
>>    optimally". The word "optimal" is a bit strong.
>>    Proposal: Change the title to "Move content focus reverse"
>>    since the primary (but not only) difference from 9.3 is the
>>    reverse requirement.
>>22) Checkpoints 10.2, 10.3, 10.4, 10.7: The expression "rely on
>>    color alone" is ambiguous. In the end, on a color display, all
>>    distinguishing marks rely on color (e.g., a solid line is a line
>>    of a different color than, say, the background color;
>>    three-dimensional effects are due to shading, etc.).
>>    Proposal: Given our checkpoint 4.3 (configure text colors), I
>>    propose that for the 10.x checkpoints, we modify the language
>>    to read "rely on text foreground and background color alone".
>>Other observations and points for discussion:
>>Thought 1) I continue to wonder whether 6.1 and 6.2 should be
>>requiring DOM implementation at a P1 level.
>>  Pros:
>>   - Supposed to promote interoperability by requiring
>>     a known API.
>>   - An API is supposed to help developers by providing
>>     access to incremental changes in content; a simple
>>     text dump after any changes may decrease performance
>>     by requiring the AT to reparse each time (though in
>>     practice, apparently some do this anyway).
>>  Cons/Questions:
>>   - AT developers may not, in practice, be interested in
>>     implementing the DOM, even though in the past they have
>>     expressed interest.
>>   - Developers can't implement more suitable APIs for a given
>>     content type (e.g., SVG) since must implement DOM 2 Core,
>>     even though a specific SVG DOM might exist.
>>   - It is not guaranteed that the *entire* DOM 2 Core
>>     is required to to provide ATs with sufficient access.
>>     I don't look forward to requiring some "subset" of DOM 2
>>     Level Core, but it would be worthwhile to determine whether
>>     nearly all of DOM 2 is required for communication with
>>     ATs
>>  Some ideas for other changes based on discussions:
>>   - Change 6.1, 6.2, and 6.3 to resemble 6.4.
>>     For example, a new checkpoint replacing 6.1, 6.2, and 6.3
>>     might be:
>>    <NEW 6.x>
>>     Programmatic access to content (P1)
>>     1. Provide programmatic read access to content.
>>     2. If the user can modify content through the user
>>        interface, provide the same functionality
>>        programmatically.
>>     3. To satisfy these requirements, implement at least
>>        one API that is either
>>         * defined by a W3C Recommendation,
>>         * a publicly documented API designed to enable
>>           interoperability with assistive technologies.
>>     4. If no such API is available, or if available APIs do
>>        not enable the user agent to satisfy the requirements,
>>        implement at least one publicly documented API that
>>        allows programmatic operation of all of the
>>        functionalities that are available through the user
>>        agent user interface, and follow operating environment
>>        conventions for the use of input and output APIs.
>>     5. An API is considered available if the specification of
>>        the API is published (e.g., as a W3C Recommendation) in
>>        time for integration into a user agent's development
>>        cycle.
>>      Note: We encourage developers to satisfy this checkpoint
>>      by using the DOM Level 2 Core specification for read
>>      and write access to XML and HTML content, or a more
>>      specific DOM (e.g., for HTML, SVG, or SMIL) when one exists.
>>    </NEW 6.x>
>>Thought 2) Change the priorities of some requirements related to
>>default values.  A long time ago, Greg Lowney suggested that we
>>should not have priority 1 checkpoints about user agent default
>>styles, but rather priority 1 checkpoints that the user be able
>>to change values, and perhaps priority 2 checkpoints about what
>>the defaults should be. I continue to think that this would be a
>>good change to make, in particular after the evaluations I have
>>done. The following checkpoints relate to default styles:
>>   7.2 Respect input configuration conventions. (P1)
>>    1. Ensure that default input configurations of the user agent
>>    do not interfere with operating environment accessibility
>>    conventions (e.g., for keyboard accessibility).
>>   10.3 Distinct default highlight styles. (P1)
>>    1. Ensure that all of the default highlight styles for the
>>    selection and content focus, as well as for enabled elements,
>>    recently visited links, and fee links in rendered content
>>    do not rely on color alone, and differ from each other, and
>>    not by color alone.
>>   10.7 Highlight current viewport. (P1)
>>    2. For graphical viewports, the default highlight mechanism
>>    must not rely on color alone.
>>  - Checkpoint 11.3 is a P2 ("Allow the user to override any
>>  binding that is part of the user agent default input
>>  configuration.") I propose making this checkpoint a P1 and
>>  making 7.2.1 a P2.
>>  - Since checkpoints 10.2 and 10.4 are P1, require the UA to
>>   allow the user to configure styles, and cover all the pieces
>>   mentioned in 10.3, make 10.3.1 a priority 2 checkpoint. I realize
>>   that without 10.3 at a P1 level, the user might not be able
>>   to distinguish some highlight styles "out of the box", but I
>>   think that should be relatively easy to fix thanks to 10.2 and
>>   10.4
>>  - I propose simply lowering the priority of 10.7.2 to P2. I note
>>   that we have no requirement that the user be able to configure
>>   the style of the viewport highlight mechanism. I don't propose
>>   that we add such a requirement.
>>Note: In the above, "10.3.1" refers to checkpoint 10.3,
>>requirement number 1.
>>Note: There are other checkpoints (7.2, about default keyboard
>>configurations. I don't propose that we change their priorities.
>>Thought 3) Clarify the relation between UAAG 1.0 and other
>>specifications. UAAG 1.0 includes requirements for specific
>>features, but also asks for conformance to other specifications
>>(e.g., HTML, CSS, etc.). I would like to add something to the
>>conformance section that clarifies that:
>>  a) Developers should follow specifications, especially when
>>     consistent with UAAG 1.0 requirements.
>>  b) UAAG 1.0 may ask developers to implement optional features,
>>     i.e., go beyond what is strictly required for conformance
>>     to another specification.
>>  c) UAAG 1.0 may ask developers to implement features that
>>     are not part of another specification.
>>  d) UAAG 1.0 does not make a definitive pronouncement about what
>>     to do when a UAAG 1.0 requirement is in direct conflict with
>>     the requirement of another specification (something we hope
>>     will be rare, and even rarer for W3C specs thanks to the
>>     good work of the WAI PF Working Group). I think we should
>>     state explicitly that in these cases, UAAG 1.0 would
>>     prefer that developers meet the needs of people with
>>     disabilities.
>>Some comments and questions about evaluations (perhaps should
>>be discussed and added to "How to Evaluate a User Agent" [2])
>>  - I think that each requirement of each checkpoint should be
>>    rated separately, rather than, say, trying to average 4
>>    ratings for the 4 requirements of a single checkpoint.
>>  - Should known bugs that are expected to be fixed count
>>    against a given rating? I think that bugs should not
>>    count against the rating, provided there is a good faith
>>    commitment by the developer to fix them. Furthermore, they
>>    should be advertised in the claim, not hidden.
>>  - How can we calibrate evaluations, i.e., make them more
>>    comparable? How do we ensure even rating across evaluations?
>>[2] http://www.w3.org/WAI/UA/2001/10/eval
>>Ian Jacobs (ij@w3.org)   http://www.w3.org/People/Jacobs
>>Tel:                     +1 718 260-9447
>Jon Gunderson, Ph.D., ATP
>Coordinator of Assistive Communication and Information Technology
>Division of Rehabilitation - Education Services
>College of Applied Life Studies
>University of Illinois at Urbana/Champaign
>1207 S. Oak Street, Champaign, IL  61820
>Voice: (217) 244-5870
>Fax: (217) 333-0248
>E-mail: jongund@uiuc.edu
>WWW: http://www.staff.uiuc.edu/~jongund
>WWW: http://www.w3.org/wai/ua

Jon Gunderson, Ph.D., ATP
Coordinator of Assistive Communication and Information Technology
Division of Rehabilitation - Education Services
College of Applied Life Studies
University of Illinois at Urbana/Champaign
1207 S. Oak Street, Champaign, IL  61820

Voice: (217) 244-5870
Fax: (217) 333-0248

E-mail: jongund@uiuc.edu

WWW: http://www.staff.uiuc.edu/~jongund
WWW: http://www.w3.org/wai/ua
Received on Wednesday, 13 March 2002 15:27:34 GMT

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