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

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From: Chris Hoffman
Date: Dec 13, 2010 7:09AM

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
>>
>>