ACTION-1490 Combobox enhancement proposal ready for review at today's meeting

My proposal for action 1490[1] is in branch mck-action1490[2].

 

Objectives:

1. Allow combobox to popup grid, tree, and dialog in addition to listbox.

2. Allow aria-controls so screen reader users can see a rendering of the
popup in reading mode.

3. Remove ambiguities from the spec to improve understanding and simplify
authoring.

4. Do it all without breaking any existing implementations.

 

Note: browser and assistive technology impact is extremely small. The
authoring changes proposed are already largely supported by both browsers
and assistive technologies. The 3 minor exceptions are:

1.      Screen readers will need to recognize the aria-controls relationship
when focus is inside the popup in order to properly process the escape key.

2. Screen readers will need to recognize boolean values for
aria-autocomplete in addition to the ARIA 1.0 token values.

3. When authors provide a boolean value for aria-autocomplete, browsers will
need to allow the boolean values. The ARIA 1.0 tokens would also still be
allowed.

 

The changes in the mck-action1490 branch are:

1. Reword the combobox definition.

2. Added normative statement saying the popup must be one of listbox, tree,
grid, or dialog.

3. Specify authors SHOULD use aria-controls but MAY use aria-owns to specify
the relationship between the input and the popup.

4. Added normative author MUST for correct use of aria-expanded.

5. Reword and simplify the focus management language.

6. Remove all text about aria-autocomplete except an author SHOULD statement
referring to the new boolean definition of aria-autocomplete.

7. Update the example code to match the new authoring requirements.

8. Add a reference to the APG.

9. Change the superclass to input.

10. Remove the required owned elements.

 

[1] Action 1490: https://www.w3.org/WAI/aria/track/actions/1490

 

[2] mck-action1490 branch:
http://rawgit.com/w3c/aria/mck-action1490/aria/aria.html