slider: not up to date with WAI-ARIA spec

[mertdeg2]

Bug, enhancement request, or proposal:

Bug

Detailed Reproduction Steps:

This can be reproduced at material demo page. Basically up/down arrows, and home/end keys are not properly handled per spec.

What is the expected behavior?

The slider directive is fully complaint with WAI-ARIA spec here: https://www.w3.org/TR/wai-aria-practices-1.1/#slider

What is the current behavior?

Left/right arrows work, but the rest of the keyboard shortcuts do not work.

What is the use-case or motivation for changing an existing behavior?

To be complaint with ARIA spec

Which versions of AngularJS, Material, OS, and browsers are affected?

• AngularJS: All
• AngularJS Material: All
• OS: All
• Screen reader: All
• Browsers: All

[mertdeg2]

@jelbourn

[jelbourn]

@Splaktar this one should be relatively straightforward to fix and get into Google AFAIK. It shouldn't affect any internal screenshot or unit tests.

[Splaktar]

We've tried upgrading a couple of components to the WAI-ARIA 1.1 spec, but there are tests within Google that use the old Chrome a11y testing tools that only support the 1.0 spec. In some cases, the changes in 1.1 conflict with the 1.0 spec. So we were not able to get those changes merged.

That said, the 1.0 Slider spec is incredibly light on details. I don't see anything in the 1.1. spec that seems to cause a conflict in this case.

It looks like we set the aria attributes more or less properly, but up/down/left/right keys are orientation specific which isn't right, and home/end/page up/page down aren't supported. I should be able to have a PR for this tomorrow.