MultiSelect accessibility improvements

[Juveniel]

General:

1. Aria-haspopup attribute is missing.

2. Consider adding aria-autocomplete="list" for announcing "listbox auto-completion list" when focusing the widget. ОК

3. Deleting an item is not announced.

CrhomeVox Testing:

Selected options not announced when the widget is focused.

NVDA Testing:

Navigating between selected items does not read them.

[jivanova]

You could use the following resources, for reference, where the behavior is similar to the combobox:

https://www.w3.org/TR/wai-aria-practices-1.1/#combobox

https://www.w3.org/TR/wai-aria-practices/examples/combobox/aria1.1pattern/listbox-combo.html

In order to announce changes in the multiselect, you might need to set aria-live attribute. Consider the below issues:

• Re-consider the role attribute of the MultiSelect TagList element #4812
• Multiselect Placeholder text is not rendered as "placeholder" attribute and the screen readers do not announce it #2866

[Juveniel]

Based on the above reports, the following improvements to the MultiSelect will be added with the 2019 R2 release:

Search Input

• aria-haspopup
• aria-autocomplete

Tag List

• role option to the selected items.
• aria-setsize to the selected items.

Deleting an item

In order for the screen readers to announce the selected options after deleting an item from the tag list, the option must be focused with the keyboard arrows first and then deleted by pressing the Backspace or Delete keys.

In addition to the above, an accessibility article will be added to the Kendo UI MultiSelect documentation that describes the above in greater details.