RE: [css3-flexbox] getComputedStyle on flex property

It makes sense for preferred-size to be different in % and 'auto'. Unlike width/height it only serves as an input for layout algorithm, it doesn't have an output value. And it may not even be in a flexbox, in which case it is impossible to resolve % and auto...

From: tc@google.com [mailto:tc@google.com] On Behalf Of Tony Chang
Sent: Tuesday, April 03, 2012 2:27 PM
To: Alex Mogilevsky
Cc: www-style@w3.org
Subject: Re: [css3-flexbox] getComputedStyle on flex property

Note that this is different from width/height for percentage values.  getComputedStyle(div, 'width') on a percentage normally returns the computed pixel size.  As you mentioned, auto is also different from width/height.  Otherwise, it's the same.
On Tue, Apr 3, 2012 at 2:19 PM, Alex Mogilevsky <alexmog@microsoft.com<mailto:alexmog@microsoft.com>> wrote:
Are values for preferred-size same as what width/height would have in computed style if they had same specified values? Then yes, it should be same.

Not sure what preferred-size should be when it is 'auto' and corresponding width or height are not auto. I think it should still be 'auto' as you suggest.

From: tc@google.com<mailto:tc@google.com> [mailto:tc@google.com<mailto:tc@google.com>] On Behalf Of Tony Chang
Sent: Tuesday, April 03, 2012 1:55 PM
To: www-style@w3.org<mailto:www-style@w3.org>
Subject: [css3-flexbox] getComputedStyle on flex property

What should getComputedStyle return when called on the flex property?  Here are some examples with my guesses:

div.style.flex = 'none';
getComputedStyle(div).flex -> 0 0 auto

div.style.flex = '1 2 3px';
getComputedStyle(div).flex -> 1 2 3px

div.style.flex = '1 2 50%';
getComputedStyle(div).flex -> 1 2 50%

div.style.flex = '1 2 1em';
getComputedStyle(div).flex -> 1 2 16px

div.style.flex = '1 2 auto';
getComputedStyle(div).flex -> 1 2 auto

Does that seem correct?