- From: <bugzilla@jessica.w3.org>
- Date: Sat, 28 Jun 2014 12:05:17 +0000
- To: public-html-a11y@w3.org
https://www.w3.org/Bugs/Public/show_bug.cgi?id=13508 --- Comment #8 from steve faulkner <faulkner.steve@gmail.com> --- (In reply to Greg Lowney from comment #0) > HTML5 should provide true support for tri-state checkboxes and menu items > (those with states of checked, unchecked, and > indeterminate/mixed/undefined), as well as other controls with > indeterminate/mixed/undefined state. This will let user agents provide > standardized user interface for such controls, and let assistive technology > provide alternative input and output for them. Not providing this would mean > authors and developers would still have to implement custom controls and > behaviors for an extremely common feature, and these would not be compatible > with assistive technology. > > We recognize that for checkbox controls there are backward compatibility > issues with the Boolean checked attribute; this could be addressed by any of > a number of means, such as providing a new attribute to indicate a > indeterminate/mixed/undefined state or changing the semantics and behaviors > of the existing indeterminate attribute so that it was no longer defined as > being purely cosmetic. > > Use case: Aidan uses speech recognition for input. When he views an > interactive web page or web-based application that uses standard HTML5 > controls, his speech recognition program can let him control them using > standardized commands, such as checking or unchecking recognized checkboxes > by saying "Check italic" or "Uncheck bold". However, when it encounters > custom controls or controls with nonstandard behaviors, he has to resort to > saying actual keystrokes, such as "Press tab. Press tab. Press tab. Press > space." He uses a web-based text editor that provides a tri-state check box > that is checked with the entire selection is italicized, unchecked when the > entire selection is not italicized, and in a third, "mixed" state when only > part of the selection is italicized. In one scenario, he accidentally checks > the Italics check box then realizes he wants to change it back to the > "mixed" state. Let's say it's implemented as an HTML5 input element with > type=checkbox, but with scripting to handle the tristate behavior (perhaps > as described in Shams' Blog: Tri-State Checkbox using Javascript - > http://shamsmi.blogspot.com/2008/12/tri-state-checkbox-using-javascript. > html); in this case the keyboard UI is not standardized, so the speech > recognition utility cannot provide a corresponding voice command. In a > second scenario, it's implemented as an entirely custom control. > > Use case: Nadia uses a screen reader with the same web-based text editor > that provides a tri-state checkbox for indicating and adjusting italics. > Regardless of whether the author used an HTML5 input element with > type=checkbox or if they used an entirely custom control, the screen reader > has no way of determining which state it's really in, and so can't convey > this to Nadia using speech. > > Use case: Ryan, a keyboard user, is using the same web-based text editor > that provides a tri-state checkbox for indicating and adjusting italics. > Unfortunately, because each web site or web-based app has to implement its > tri-state checkbox itself, they often implement entirely different keyboard > UI, and so when Ryan comes to one he cannot easily figure out how to use it > with the keyboard. I have tested the indeterminate IDL attribute in Firefox/IE and Chrome. I found that when the attribute is set to true all the above browsers provide a visual indication of the indeterminate state. indeterminate=true is also coveyed as the MSAA 'mixed' state in Firefox and Chrome, but not Internet Explorer. I have filed a bug on IE https://connect.microsoft.com/IE/feedback/details/907974/html-checkbox-indeterminate-idl-state-not-exposed-in-accessibility-layer test case: http://stevefaulkner.github.io/html-mapping-tests/browser-tests/checkbox-states.html -- You are receiving this mail because: You are on the CC list for the bug.
Received on Saturday, 28 June 2014 12:05:19 UTC