ACTION-1442: Create spec. text for aria-currentfor="IDREF" and aria-current="true/false", related to issue-587

Bryan, be aware of the language used in other parts of the spec for boolean and IDREF values. For example, the first sentence of attrs with IDREF values always starts with the word, "Indentifies…" The first sentence of attrs with "true/false" or "true/false/undefined" values always starts with the word, "Indicates…"

I wanted to post this sooner than later, so I'll do this here for now unless I should send this somewhere else; I'm still learning the process. Also, if I should change the state of the action item, please let me know.

Below I've pasted the proposed spec text for both attributes. For the time being, I've made this general, since use cases for this type of functionality may include groups of variable element types, such as links, divs, images, list items, etc, and there is no way to predict which will be used by developers to convey step indicators.

aria-current (state)

Indicates the currently "active" state of related elements.
See related aria-context.

The aria-current attribute indicates whether the element is active (true), or not active (false). When the value is undefined, no active state should be conveyed by the user agent.

The aria-current attribute is similar but not identical to the aria-selected attribute.
The aria-selected attribute indicates the current "selected" state of children within various widgets. In contrast, aria-current indicates the current "active" state of related elements within a defined contextual scope.

Authors must ensure that related active elements define contextual scope using aria-context, in order to identify that they are related elements.

Authors must not use aria-current as a replacement for aria-selected.

Characteristics of aria-current:
Used in Roles: All elements of the base markup
Value: true/false/undefined

Values of aria-current
true: The element is active.
false: The element is not active.
undefined (default): The element has no active state.

aria-context (property)

Identifies an ancestor element in order to define contextual scope for a group of related elements that share the same ancestor.
See related aria-current.

The value of the aria-context attribute is an IDREF that references one ancestor element in the document by ID. The reason for adding aria-context, is to expose a contextual scope to assistive technologies for a group of related elements that are contained within the same ancestor element.

Authors must not use aria-context as a replacement for aria-owns, nor to reference an element that is not an ancestor of the element in the DOM hierarchy.

Authors must ensure that related elements reference the same ID for the shared ancestor element. In other words, a group of related elements can have only one explicit contextual scope.

Characteristics of aria-context:
Used in Roles: All elements of the base markup
Value: ID reference

From ARIA Meeting June 2, 2014

Introduce the following to the text:
1. we have an aria-current which applies to an element in a navigation container
2. aria-currentfor that would apply to any container, takes a single IDREF

Leonie to post text to the list for comments from James and Rich

Leonie's proposal: http://lists.w3.org/Archives/Public/public-pfwg/2014Sep/0087.html

Leonie's proposal: http://lists.w3.org/Archives/Public/public-pfwg/2014Sep/0087.html

creating new action for Leonie