Re: change proposal: Provide accessibility implementation information (in the Canvas 2d Context specification) for focus rectangle and caret

Hi Maciej,

Text Caret Selection changed would work from the selected text in the DOM.
It does not operate off coordinates. ... However, that said, let me try to
work with a selection proposal and see what people think. What it will come
down to (whatever we call it) is how we describe to the author and how the
browser handles it.

Rich

Rich Schwerdtfeger
CTO Accessibility Software Group


                                                                           
             Maciej Stachowiak                                             
             <mjs@apple.com>                                               
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                                       Steven Faulkner                     
             03/15/2010 03:53          <faulkner.steve@gmail.com>,         
             PM                        public-canvas-api@w3.org, HTMLWG WG 
                                       <public-html@w3.org>, HTML          
                                       Accessibility Task Force            
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                                                                   Subject 
                                       Re: change proposal: Provide        
                                       accessibility implementation        
                                       information  (in the Canvas 2d      
                                       Context specification) for focus    
                                       rectangle and caret                 
                                                                           
                                                                           
                                                                           
                                                                           
                                                                           
                                                                           





On Mar 15, 2010, at 1:07 PM, Richard Schwerdtfeger wrote:



      <RSS>I confirmed with Frank Olivier (Microsoft) that when you turn on
      caret browsing the follows the end of the caret selection drag. Also,
      on my Mac, although the caret does not render during selection. If
      you drag the selection and then hit the right arrow key the caret
      appears at the end of the selection. However, if you hit the down
      arrow it goes to the next line at the X Position representing the
      start of the drag. We need to have the screen magnifier follow the
      end of the selection and even if the caret is not visible I feel you
      want to follow the end of the select or caret location. The caret,
      during a selection should follow the end the selection drag. It does
      on Windows for caret browsing mode. The Accessibility API used to
      move the "point of regard - a UAAG 1.0 term", on systems I work on do
      so by following the caret position and not the selection which is a
      selection range vs. a location. I can't see having the magnifier
      following a selection range as it could be the whole page.



      </RSS>

I think it may not be obvious to Web application authors that they should
expose the "end of selection" position as a caret position. I think an API
that would be more clear is to for the Web content author to provide to
coordinates for the start and end of the selection, and the UA can decide
how to map that to accessibility APIs (it could use the start or the end,
or do whatever else is appropriate with the given assistive technology). I
think that's cleaner and more appropriate than expecting Web content
authors to know that they should report the selection end as a caret
position.

It also seems like this would allow both TEXT_CARET_MOVED and
TEXT_SELECTION_CHANGED from IA2 to be handled by the UA.

Regards,
Maciej