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Re: SPAM-LOW: Re: CSS content property and empty image alt values

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From: steven
Date: Dec 13, 2010 7:51AM

Hi Chris,

CSS is indeed applied once the HTML document has been rendered to the page,
but so is alot of JavaScript which can still be read by screen readers.
Hence my query about inserting images into the design using CSS content
property ... do screen readers consider such content to be read out? Or
simply ignored as presentational content?

Steven


-----Original Message-----
From: <EMAIL REMOVED>
[mailto: <EMAIL REMOVED> ] On Behalf Of Chris Hoffman
Sent: 13 December 2010 14:10
To: WebAIM Discussion List
Cc: WebAIM Discussion List
Subject: Re: [WebAIM] SPAM-LOW: Re: CSS content property and empty image alt
values

Is it even possible to insert an image using CSS content properties? As far
as I understand it, CSS transformations happen _after_ the HTML has been
rendered, so CSS content is limited to pure unmarked text. Though, I admit
to not being fully up to speed on CSS3, so maybe this has changed.

Chris



On Dec 10, 2010, at 10:35 AM, "steven" < <EMAIL REMOVED> >
wrote:

> Hi Dawn,
>
> I was specifically wanting to place images into pages using the CSS
content
> property without actually placing them in the flow of the DOM (which to my
> knowledge, is what screen readers read). That way, I could avoid using
empty
> alt images in the DOM, but was wondering if placing images into the design
> using CSS content property would trigger similar behaviour in screen
readers
> as they would if using images in the DOM (such as alerting the user that
> there is an image and reading out the alt text).
>
> I know CSS background images are not read by screen readers, but wondered
if
> images placed using CSS content property would act differently to CSS
> background images!? Being that they are placed into the page in a similar
> way as DOM images as you can wrap text around them etc!? Hence my
> attraction.
>
> Steven
>
>
> -----Original Message-----
> From: <EMAIL REMOVED>
> [mailto: <EMAIL REMOVED> ] On Behalf Of
> Dawn Budge
> Sent: 10 December 2010 13:42
> To: WebAIM Discussion List
> Subject: Re: [WebAIM] SPAM-LOW: Re: CSS content property and empty image
alt
> values
>
> Generally yes, anything which is presentational belongs in the CSS. The
> only time that becomes a problem is when you need to rely on the image
> dimensions for anything and they are not predictable (e.g. CMS-generated
> content), or you want content to flow around an image.
> Are you trying to achieve a specific thing with using the content
> property?
>
> ----------------------------------------
> From: "steven" < <EMAIL REMOVED> >
> Sent: 10 December 2010 13:11
> To: "WebAIM Discussion List" < <EMAIL REMOVED> >
> Subject: SPAM-LOW: Re: [WebAIM] CSS content property and empty image alt
> values
>
> Hi Chris,
>
> Imagery to a visual person would generally not need explanation, if it is
> purely presentational. Hence why I see the advantage of using CSS for
> images
> rather than images within the DOM, therefore voiding the need for such
> images (and blank alt attributes) to be part of the actual content (in
> cases
> where images would not be content).
>
> Diagrams would generally be regarded as content and should have alt text,
> but I still think icons and banners etc generally are not content, so
> wondered if screen readers would extend and honour the presentational
> nature
> of CSS to make presentational images feasible (after all, XML and HTML5
> have
> been unable to do this alone, despite being created to divide content from
> form and function). I would also remove menus and hyperlinks from content
> too if I had my way and introduce a separate browser/app method of
> connecting and navigating content, but this continues to be overlooked
> whilst browser developers and standards developers work separately.
>
> Regards,
>
> Steven
>
> -----Original Message-----
> From: <EMAIL REMOVED>
> [mailto: <EMAIL REMOVED> ] On Behalf Of Chris Hoffman
> Sent: 09 December 2010 14:53
> To: WebAIM Discussion List
> Cc: WebAIM Discussion List
> Subject: Re: [WebAIM] CSS content property and empty image alt values
>
> Hi Steven,
>
> According to a blog post from The Filament Group
> (http://filamentgroup.com/lab/dingbat_webfonts_accessibility_issues/),
> VoiceOver reads generated CSS content. The implication is that other
> screenreaders generally do not.
>
> I don't quite understand how that relates to presentational imagery,
> though.
> Could you explain?
>
> Chris
>
> On Dec 9, 2010, at 6:11 AM, "steven" wrote:
>
>> Is anybody familiar with screen reader support (or intentional lack of
>> support) for the CSS 'content' property?
>>
>> I ask because I know that images generated by HTML markup are known to
> be
>> read by screen readers, but I am thinking if CSS content itself is not
> read,
>> then there can often be cases where presentational imagery serves no
> place
>> in the HTML DOM and in such cases, would be better than serving images
> with
>> empty alt values.
>>
>> What are peoples thoughts and experience on this.
>>
>> Regards,
>>
>> Steven
>>
>>