- From: Sam Ruby <rubys@intertwingly.net>
- Date: Thu, 02 Aug 2012 13:44:31 -0400
- To: Richard Schwerdtfeger <schwer@us.ibm.com>
- CC: Maciej Stachowiak <mjs@apple.com>, "public-html@w3.org WG" <public-html@w3.org>
Which of these objections were stated in response to the survey? Do intend to collect and pesent new information? - Sam Ruby On 08/02/2012 12:59 PM, Richard Schwerdtfeger wrote: > > Rich Schwerdtfeger > > Maciej Stachowiak <mjs@apple.com> wrote on 07/17/2012 08:56:10 PM: > > > From: Maciej Stachowiak <mjs@apple.com> > > To: "public-html@w3.org WG" <public-html@w3.org>, > > Date: 07/17/2012 08:58 PM > > Subject: Working Group Decision on ISSUE-205: caret-location-api > > > > > > The decision follows. The chairs made an effort to explicitly address > > all arguments presented in the Change Proposals on this topic as > there were no > > additional responses in the poll itself. > > > > *** Question before the Working Group *** > > > > There is a basic disagreement in the group on whether additional > > accessibility functionality for canvas text editing, tracked as ISSUE > > 205. We have two distinct proposals for this question, and a straw poll > > for objections. > > > > http://www.w3.org/html/wg/tracker/issues/205 > > http://www.w3.org/html/wg/wiki/ChangeProposals/CaretSelectionRevised > > http://www.w3.org/wiki/No_edit_change_proposal_for_canvas_text_editing > > http://www.w3.org/2002/09/wbs/40318/issue-205-objection-poll/results > > > > > > == Uncontested parts of the proposals: > > > > The following points were made and not disputed, and in some cases > > explicitly stipulated by both proposals: > > > > - There exist some applications which do in-canvas text editing > > (specific examples: Ludicart Drawing Tool, LibreOffice Online) > > - In-canvas text editing is lacking in accessibility. > > - Combining text editing with canvas is a valid use case (though how > > best to do it is disputed). > > - The "CaretSelectionRevised" proposal provides sufficient > > functionality to support accessibility of in-canvas text editing. > > - Superimposing text fields on top of the canvas is an existing > > alternative approach to meeting these use cases (though it is > > disputed whether it is complete, or the best approach). > > A key reason for the CaretSelectionRevised proposal is to allow for > magnifier tracking in during content selection. A superimposed text > "field" does not allow for selection of rich text content that could > span paragraphs of information with embedded content. > > > - Superimposing text fields is sufficient for simple use cases, though > > whether it is sufficient for more advanced use cases is disputed. > > - In-canvas text editing has many weaknesses and limitations, > > requiring significant reimplementation and making it challenging > > (perhaps in somc cases impossible), to deliver some > > non-accessibility editing capabilities. > > > > They are assumed valid in the analysis below. > > > > > > == Use cases for in-canvas text editing: > > > > It is not disputed that canvas-based applications which also do text > > editing are a valid use case and are actually used in the wild. It is > > also accepted that such applications must be made accessible. This > > would form a strong objection to any proposal that does not address > > these use cases. This is not disputed for the "CaretSelectionRevised" > > proposal, but it is disputed for the > > "No_edit_change_proposal_for_canvas_text_editing" proposal. So we must > > examine the latter proposal in more detail to fully evaluate this > > objection. > > > > > > == Superimposing text fields as an alternative: > > > > Superimposing text fields over a canvas is conceded to be sufficient > > for simple use cases, such as editing a label on a graph. > > > > However, one proposal argued that superimposing text fields is > > insufficient for rich text editors using "embedded font layout, custom > > fonts, and arbitrary objects and glyphs". No supporting evidence was > > given for this claim. The other proposal says that superimposing a rich > > text editing control is sufficient for more complex use > > cases. Microsoft Office online and SkyDrive were cited as examples > > using this technique. > > > A text field is limited to text. For things like entering simple text > labels this is adequate. However, if one were to select content across > rich text this would include: embedded tables (which have context > information associated such as headers), bitmaps, drawings, etc.. Those > items, by definition, do not equate to text and during content selection > the additional semantics cannot be conveyed to a blind user as they > don't exist in the text field. It is for this same reason that > applications like MS Word (desktop) would not overlay a text field so > large that it would cover the entire document for sighted users creating > an accessibility issue, that did not exist, for sighted users. > > Nowhere in the other proposal > (http://www.w3.org/wiki/No_edit_change_proposal_for_canvas_text_editing) > does it state that overlaying a text editing control over the existing > control allows someone who is blind to be able to select content. There > is no statement anywhere in this proposal that states that the > technology works fully with today's screen readers like JAWS. One cannot > make the assumption that just because it was implemented with a text > field that the solution itself is robust enough to support a screen > reader. Having actually been part of a team that has built a screen > reader and having spoken with a major AT vendors they agree that the > floating text field solution does indeed have problems in conveying the > user's context within the document. Once you leave the text field text > selection tracking fails > > Although I don't have access to the online version of Microsoft Office I > do have access to the desktop LibreOffice. LibreOffice superimposes > individual text fields within groups over the content and the text can > be read. The problem we are trying to solve is text selection tracking > for magnifiers and screen readers. Nowhere does it state in this > proposal that you can can select text across multiple text fields and > convey to the screen reader user or blind user the context as to where > they are in the document as within the text field the information does > not exist. I ran selection of text across LibreOffice and it did in fact > fail to allow either a magnifier or a screen reader to track the > location of the selection point across text fields. VoiceOver on MacOSX > 10.7.4 was able to read the text within the text fields but text > selection failed completely and it failed to track the selection across > multiple lines of text and embedded graphics. I do not believe this is a > failing in VoiceOver. In LibreOffice each textfield was limited to a > range of text and VoicOver actually draws a bounding box around that > field illustrating that when you go and select many lines of text and > embedded drawing objects you lose the context of what you are selecting. > > In the future I would ask that when the chairs read a proposal they also > ask whether the solution fully works with assistive technology as this > is the problem we are trying solve. Simply saying that a solution > "works" with Microsoft Word and Skydrive does not mean it works for > people with disabilities. > > > On the whole, it seems like overlaying a text field or a rich text > > control is a viable alternative; no evidence is provided otherwise. In > > fact, a specific example is provided of the rich text case. Thus, the > > objection to the overlay solution is taken to be a very weak objection > > for lack of evidence. > > > > > > == New vs existing features: > > > > We conclude that both proposals meet the required use cases. Normally > > the presumption is against adding new features when existing features > > would satisfy the use cases in question. The new feature would have to > > show compelling benefits that make it far better for at least some > > uses, and which are not offset by the disadvantages. > > > The conclusion was based on not trying the approach with an assistive > technology and seeing the problems which I do hope the chairs are now > able to see. > > > > > == Argument from existing use of canvas-based editing: > > > > One survey objection states, with regard to the > > "No_edit_change_proposal_for_canvas_text_editing" proposal: > > > > As already noted, this stricture has not worked. There's no > > evidence this will change. We have not heard that LibreOffice will > > withdraw, nor have we any evidence that some author will not ask > > something as simple as "Enter your name here:" in canvas. So, if > > the WG cannot prevent text editing in canvas, it should recognize > > that a11y will be harmed if the technology to support assistive > > technologies is excluded. Please do not undermine a11y over an > > unwinnable preference. > > > > Considering this statement generally, it doesn't seem to be the case > > that *no* canvas-based editor will change its approach. This seems to > > be false as a universal claim. Mozilla Bespin (later Skywriter and > > then Ace) was a frequently cited canvas-based text editor which has > > moved to non-canvas-based editing. > > > > To interpret this argument in the strongest possible way, let us take > > it as a claim specifically with regards to LibreOffice Online, a > > product that has been cited directly. No technical reason is provided > > for why LibreOffice Online could not use existing HTML features to > > achieve accessibility. No technical obstacles are cited. > > > The issue is not whether LibreOffice could create an RTE with HTML. It > is the fact that they chose canvas to do it. Google Docs did not use > contenteditable either. I did ask Dominic Mazzoni as to why the Google > Docs team chose to not use canvas. He sighted one example as the concept > of pages not being in contenteditable. Also, a quick look of the YouTube > video of LibreOffice online shows inline drawing functionality in the > presentation whose functionality does not reside in contenteditable. > http://www.youtube.com/watch?v=wdqgSB9axZQ > > > That said, you have: > > Microsoft 365 > LibreOffice > Google Docs > > and none of them has implemented contenteditable. It should be up to the > chairs of the HTML working group to ask them those questions and not > place the burden on the people who are working to make a technology > accessible. This is comparable to the chairs saying why use Microsoft > Word on the Mac, which is not accessible, and use the Apple office suite > solution because it is. It has absolutely nothing to do with a technical > solution. If a company were to deploy LibreOffice to their employees > today they would not be able to use it. The answer is NOT to tell the > LibreOffice people to write LibreOffice as a contenteditable document. > What's more <canvas> IS an HTML feature. Unless the HTML working group > wishes to remove it then we should address its accessibility. > > > This is on some level a valid objection. However, LibreOffice Online > > is not a released product; it exists (as far as can be determined) > > only as a prototype, and can be seen only in the form of a demo > > video. As seen in the cited email announcement, this product was > > created with the knowledge that canvas text editing was controversial, > > and that accessibility functionality was missing. Given this, the > > argument based on inconvenience of change can only be given limited > > (moderate) weight. > > > LibreOffice online is at version 3.5 online. It is not clear that it is > at product level. I do not know if the LibreOffice team was aware of > this accessibility deficiency but I do believe, as a product, that they > are in the early stages - releases aside. It is undisputed that > LibreOffice has not addressed accessibility for their online version > which currently only works on Windows. I tried it on Windows and it did > not work with the screen reader I tried. > > Canvas accessibility functionality is missing as at the time they began > work on LibreOffice we had not yet made a lot of progress on canvas > accessibility and in fact one could also argue that HTML5 is not done, > accessibility aside. > > > > > == Non-accessibility Limitations of direct in-canvas text editing: > > > > As noted above, in-canvas text editing has many weaknesses and > > limitations, requiring significant implementation work to provide > > various non-accessibility features. Examples include international > > text input (IMEs) and system spellchecking. > > > > While this is true, the chairs should not be ignoring an accessibility > issue simply because something is hard to do today. I am quite sure that > when Microsoft Word went from a text based interface to a GUI that it > was not a trivial task. In fact, a new W3C API is being developed to > facilitate the development of IMEs and it can be found here: > http://www.w3.org/TR/2012/WD-ime-api-20120524/ > > I would also argue that early releases of the Windows GUI was not a lot > different from canvas today in that canvas provides a 2D drawing API and > as we add features like hit testing it will have even more of the needed > functionality required to produce a rich GUI experience. > > > The caret/selection API would not address these, as the warning text > > and the alternative technique of overlaying a text field or rich text > > control does. > > > > It is not intended to address internationalization. Overlaying a text > field does not in fact address rich what the additional caret/selection > tracking API does as highlighted earlier and the chairs have given no > evidence that they have tested content selection with an assistive > technology across large amounts of rich text with embedded content. Also > the chairs have not discussed with whether a floating text field > interface would provide a rich usable experience on par with what a user > experiences with say a native Microsoft Office application. Having > actually built a screen reader and discussed this issue with a major AT > vendor the conclusion is that it does not. > > Rather, the chairs simply stated that two applications employed text > fields for text entry. Here is the the actual text from the "do nothing" > proposal: > > "For cases where more rich editing is required, other solutions already > exist: Online versions of Microsoft Office and SkyDrive already > implement a rich text editor by overlaying an editing control on top of > the main document." > > > > > One survey objection counters this, saying "Yet, LibreOffice has > > already built a rich text editor in canvas that supports multiple > > languages." This statement is vague as written. It's not clear if this > > means that LibreOffice supports all or most of the challenging text > > editing features, a subset including all the features related to > > internationalization (including IMEs), or merely some form of > > multi-language support. > > > > > > The interpretation as "some form of multi-language support" would not > > rebut the argument that canvas-based text editing is deficient in > > crucial ways. It is too limited a claim. Therefore let us examine the > > stronger forms. > > > > If the claim is that LibreOffice Online supports all > > internationalization-related text editing features, including support > > for system-built in international text input methods, then this is an > > extraordinary claim. Such an extraordinary claim would require > > extraordinary evidence. Because LibreOffice Online is only a prototype > > and not yet (apparently) available online, it is impossible to check > > the claim directly. A vague claim that LibreOffice Online "supports > > multiple languages" is not sufficient evidence for this type of claim, > > if that is indeed the claim being made. > > > > This is a gross overstatement of what was stated in the survey poll. The > actual text reads: "Yet, LibreOffice has already built a rich text > editor in canvas that supports multiple languages." > > In no way does that say ALL languages. What is not disputed is that the > online version is a prototype. > > > > Overall, then, the severe limitations of canvas text editing form a > > moderately strong objection to the CaretSelectionRevised > > proposal. Since (apparently) the use cases for accessible editing in > > canvas-based apps can be otherwise met with the overlay technique, the > > fact that the direct in-canvas technique would omit key functionality > > is an important point to consider. > > > > > > == Arguments that were given no weight: > > > > - "I object to having this text in the HTML5 spec. as it states that > > authors should not do rich text editing using canvas because it is > > technically hard..." -- Neither proposal suggests removing the > > warning text in the HTML5 spec. Thus, this argues for a proposal > > that is not on the table. > > > > - "..the company advocating this change proposal is the largest > > producer of rich text editing products brings into question, for me, > > the motivation for making this change proposal." -- Ad hominem. > > > > - "If it were not technically feasible to produce a rich text editor > > in canvas or it were proven that we could not produce an accessible > > rich text editor with canvas then those arguments would be grounds > > for having this text in the document..." -- No one made either of > > the claims rebutted here. > > > > > > *** Decision of the Working Group *** > > > > Therefore, the HTML Working Group hereby adopts the <data> element change > > proposal: > > > > http://www.w3.org/wiki/No_edit_change_proposal_for_canvas_text_editing > > > > Of the Change Proposals before us, this one has drawn the weaker > objections. > > > > I did my best to address the claims by the chairs above. It is clear > that proposal that essentially says "do nothing to support rich text > editing" did not prove that a floating text field would provide for rich > text *accessibility*. > > There was no evidence that the author spoke to assistive technology > vendors nor that they have the assistive technology background to make > the claim that this is a good solution to the problem. His claim was > simply that to products employed a floating text field. I have looked at > an implementation of this strategy and I have determined it to be > inadequate and I have discussed it with a major Windows screen reader > vendor and they also found the approach to give a poor user experience > to a blind user. It is also clear that the chairs read the "do nothing" > proposal and made the extraordinary assertion that that a floating > textfield provided an usable accessibility experience which it cannot as > text field cannot provide rich semantics provided for in the document > itself nor can it allow for caret tracking across broad selections of > text including those that reside inside table cells. Products like the > desktop version of Word and Symphony provide direct access to the their > DOM and allow the caret to be aligned with actual content in the > document as well as their semantics. A floating text field does not NOT > that. This proposal does: > http://www.w3.org/html/wg/wiki/ChangeProposals/CaretSelectionRevised as > it is designed to work with the fallback content and the actual location > of the caret and selection location on the physical canvas. > > What I do not dispute is: > > - rich text editing in canvas is in its early stages. > - IME is temporarily difficult but new APIs are being created to address > this on the web to make it easier > - The LibreOffice team did not address accessibility in their online > version, nor did they approach anyone from the HTML5 working group for > help. I personally emailed Michael Meeks (LibreOffice) to discuss this > and did not get a response. The reasons were not clear. > - For simple text entry, such as entering a label, a floating textfield > will suffice > > */For these reasons I would ask that the chairs move issue 131 to > HTML.next and save proposal > /*http://www.w3.org/html/wg/wiki/ChangeProposals/CaretSelectionRevised*/ for > review at that time. This will give more time for canvas, > contenteditable, web-based IME support, and cross-cutting accessibility > support to develop and mature. If the chairs agree to then I would > support the chairs decision for HTML5 as a temporary one requiring > greater view in the next version, otherwise I will need to formally > object to the chairs decision. /* > > > > > > == Next Steps == > > > > Since the prevailing Change Proposal does not call for a spec change, > > no further action is required. ISSUE 205 will now be closed. > > > > > > == Appealing this Decision == > > > > If anyone strongly disagrees with the content of the decision and would > > like to raise a Formal Objection, they may do so at this time. Formal > > Objections are reviewed by the Director in consultation with the Team. > > Ordinarily, Formal Objections are only reviewed as part of a transition > > request. > > > > > > == Revisiting this Issue == > > > > This issue can be reopened if new information come up. Examples of > > possible relevant new information include: > > > > * Identification of one or more actual tools (more is better) with > > requirements that can't reasonably (as determined by the authors of > > these tools) by satisfied by the existing HTML Canvas functionality, > > potentially augmented by techniques such as superimposing text > > fields; explicit identification of these requirements and > > limitations; identification of features which specifically address > > these limitations; and an indication by the authors of the tools > > cited that they would actually use these features if they were > > provided. > > > > * Stronger, verifiable evidence that applications based on pure-canvas > > text editing can overcome the many cited limitations. > > > > >
Received on Thursday, 2 August 2012 17:45:01 UTC