- From: Richard Schwerdtfeger <schwer@us.ibm.com>
- Date: Mon, 7 Feb 2011 17:49:43 -0600
- To: Maciej Stachowiak <mjs@apple.com>
- Cc: Charles Pritchard <chuck@jumis.com>, david.bolter@gmail.com, franko@microsoft.com, public-canvas-api@w3.org, public-html-a11y@w3.org
- Message-ID: <OF42433DFB.7439B6A1-ON86257830.0081C41E-86257830.0082E4E1@us.ibm.com>
I just saw this. Apologies Maciej. 1. If an author of a canvas application wished to do text editing and a screen reader were going to find out where the grammar or spelling errors are they would need to find it in the content. That can be done in contenteditable sections or and author of a cloud-based application, like Google Docs, may wish to have their own spelling or grammar checker that is consistent across client platforms. Content could be passed to a web service for analysis and there is no need to depend Apple's own design. I can't imagine Microsoft Office using the same spelling and grammar checker as Apple's office suite. Am I right? 2. A screen magnifier needs to know where know the location of spelling and grammar errors so that it can position the user at those locations during zooming. The canvas fallback content, used to make canvas accessible, does not have coordinates that match the screen locations where they actually appear on canvas. 3. Regarding caret and selection we agree that we could use the normal scripting API for the selection. However, it would be nice if browser manufacturers could use the same API. IE matches no other browser here. 4. Caret/Selection When the user moves the caret or the selection position on the screen the magnifier needs to follow the screen position of the caret or the point you are pointing your finger or mouse to perform the selection. We need the ability for the author to pass that information to accessibility API services in the browser so that a magnifier can follow along. Rich Schwerdtfeger CTO Accessibility Software Group From: Maciej Stachowiak <mjs@apple.com> To: Richard Schwerdtfeger/Austin/IBM@IBMUS Cc: public-canvas-api@w3.org, franko@microsoft.com, david.bolter@gmail.com, Charles Pritchard <chuck@jumis.com>, public-html-a11y@w3.org Date: 01/06/2011 06:51 PM Subject: Re: Solution to grammar, spelling, and I don't understand the goal of this interface. Grammar and spelling checking are normally system services (at least, on Apple's platforms this is true). The flow you would need to integrate them with canvas would be to call into the OS to find out what words are misspelled or what phrases have incorrect grammar. The actual UI offered in native apps goes beyond just drawing error markers and also includes dialogs that let you step through errors and fix them. I don't understand how this proposal fits with that flow. For the caret and selection aspects - the DOM already has an API to specify a selection range. It seems like you could easily put the selection inside the canvas subtree. I don't see what this use of the <mark> element adds. Regards, Maciej On Jan 6, 2011, at 4:28 PM, Richard Schwerdtfeger wrote: So, over the break we (David, Charles, and I) discussed a way to address the grammar, spelling, and caret tracking issues in the canvas subtree without having to introduce new HTML tags or requiring exposing new APIs that provide this information to canvas application authors having to synch the canvas to the canvas subtree. The alternative solution is to use ARIA with some slight modifications: In the canvas subtree we would simply make use of aria-invalid which already exposes grammar and spelling errors and it is a global attribute in ARIA 1.0: <mark aria-invalid="grammar"> See run Spot. </mark> or <mark aria-invalid="spelling">See Spot Rn. </mark> As for selected content we simply do apply aria-selected="true" to any content: <mark aria-selected="true"> ... </div> The modification would be to make aria-selected an ARIA global attribute and address the accessibility API mapping for it. This is very straight forward. For a caret we simply have a collapsed section: <mark aria-selected="true"></mark> This is all very clean, requires minimal impact to the existing browser implementations and in fact puts more control in the hands of cloud-based offerings where they are not limited to what the browser is doing for them in contenteditable sections. Frank would you and the IE team support this approach? I would like to discuss this on Monday's call as well. Rich Schwerdtfeger CTO Accessibility Software Group
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Received on Monday, 7 February 2011 23:50:20 UTC