ACTION-2021: Draft text for default max and min spinbutton values

Draft text for default max and min spinbutton values

Joanmarie Diggs
Due on:
February 18, 2016
Created on:
February 11, 2016
Associated Issue:
Related emails:
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Related notes:

The implicit values for aria-valuemin, aria-valuemax, and aria-valuenow are the same as the default values of the equivalent native host language element.

New branch created:
Spec view:

Setting status to Pending review.

Joanmarie Diggs, 18 Feb 2016, 18:01:00

New version: Went with infinity.
Spec view:

Joanmarie Diggs, 25 Feb 2016, 22:51:26

Consider this markup, where aria-valuenow is missing (author error):

<div role="spinbutton" aria-valuemin="-100" aria-valuemax="-10"> ... </div>

According to the latest spec text, the default value for missing aria-valuenow is 0 (zero) for this case. But, how can the current value be greater than the maximum?

My guess, for missing aria-valuenow:
1. if there is a valuemin and a valuemax, set valuenow to the midpoint.
2. if there is only a valuemin, set valuenow to valuemin.
3. if there is only a valuemax, set valuenow to valuemax.
4. if there is no valuemin nor valuemax, set valuenow to zero.

Joseph Scheuhammer, 29 Feb 2016, 21:58:44

I"m withdrawing the suggestion in the previous note. The HTML5 <input type="number"> allows the @value to be undefined, in which case it becomes the empty string, which is parsed to a floating point number of 0.0.

Still, the visual display shows an empty spin button in this case, and communicates "no value set yet". The AAPI VALUE interfaces need some way of representing this. IA2's currentValue(&val) function returns true/false, and puts the value into the 'val' argument. When the function returns false, that indicates that, "there is nothing to return", and the 'val' is set to VT_EMPTY [1]. That can be used by ATs to indicate "there is no value set yet". Maybe.


Joseph Scheuhammer, 1 Mar 2016, 15:43:19

<jamesn> how about this? "Authors must set the aria-valuenow attribute. Authors should set the aria-valuemin attribute when there is a minimum value, and the aria-valuemax attribute when there is a maximum value. If missing or not a number, the implicit values of these attributes are as follows:"
<jamesn> "The implicit value of aria-valuemin is that there is no minimum value"
(ditto for max)

Note to self: We need to wait 48 hours.

Joanmarie Diggs, 3 Mar 2016, 17:51:20

I have updated the text in my branch to reflect James' text:

Now it's viewable at for the CfC

Joanmarie Diggs, 3 Mar 2016, 18:25:25

Committed to master:

Setting State of this action to CLOSED.

Joanmarie Diggs, 10 Mar 2016, 18:01:30

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