How to apply/use longdescref

[Stacey]

Hello:
I'm looking to use <londescref> to allow me to create a larger amount of alt text, and I'm confused as to how to implement it.
I found https://www.oxygenxml.com/dita/1.3/spec ... scref.html and used the <longdescref href="my-pet-llama.dita"/> format to pinpoint a section in a reference topic (and then the reference topic itself), but when I output to Webhelp and hover or click on the associated image, I don't see that content. I also don't see it in PDF output.
We use both PDF and WebHelp output. For WebHelp, I sort of assume it would take them to a page not in the table of contents; for PDF, would it be an appendix? Or would the linked content be read out in place of Alt text?
Any additional information would be helpful.

Thanks!

[Radu]

Hi Stacey,
I admit I do not know much about the DITA longdescref, I never used it myself and I think there is no other Oxygen client using it as well.
Looking at how it's implemented right now, so if in the DITA topic you are using it on an image reference:

Code: Select all

<image href="../../images/Iris_sanguinea.jpg" scale="50">
            <longdescref href="../introduction.dita"/>
        </image>

and publish to HTML5 or WebHelp, you get the HTML equivalent for it looking like this:

Code: Select all

<img class="image" longdesc="../introduction.html" src="../../images/Iris_sanguinea.jpg" height="166" width="125">

For PDF outputs it is not used at all.
And it's not related to alternate image text, it's something else.
The @longdesc attribute was part of the HTML specification but it was deprecated and does not seem to be supported anymore in modern browsers.
I think the original indent of the HTML <img> longdesc was to provide a link which was followed when clicking the image:
https://developer.mozilla.org/en-US/doc ... t/longDesc
But this can be done also with DITA by inserting an <xref> and then inserting the <image> inside it.
So I think the DITA standard adopted "longdescref" because there was an HTML equivalent but as HTML no longer supports (and probably never did) support the "longdesc" attribute on the <img> element this DITA element is not useful.
It could become useful if maybe some Javascript functionality would be added to the WebHelp output for example and use that longdesc attribute in some way, maybe to show some kind of fancy tooltip when hovering the image.

About the initial use case:

create a larger amount of alt text

Maybe you can use the "<alt>" element inside the <image> element, maybe use conrefs to refer to an <alt> element from another place and reuse the alternate description.

Regards,
Radu

[Stacey]

Okay. Thank you for your insight!