epub 3.0 with ncx, example please?

[xmlgirl]

I'm working on my first 3.0 epub and having trouble with listing ncx in the opf as a backup for older readers. The idpf EPUB Validator says

Spine item with non-standard media-type 'application/x-dtbncx+xml' with no fallback

I have this in the manifest

<item id="ncx" href="toc.ncx" media-type="application/x-dtbncx+xml"/>

and this in the spine

<spine>
<itemref idref="cover" linear="no"/>
<itemref idref="book" linear="yes"/>
<itemref idref="toc" linear="no"/>
<itemref idref="ncx" linear="no"/>
</spine>

Thanks!

[DiapDealer]

I'm not sure if there's anything special about configuring a fallback ncx in epub3, but regardless ... I can't imagine that the ncx would be listed as an itemref in the spine—linear or no.

I'm pretty sure a fallback ncx is handled just like an ncx in epub2 --

In the manifest:
<item id="ncx" href="toc.ncx" media-type="application/x-dtbncx+xml"/>

and the spine:
<spine toc="ncx">
<itemref idref="cover" linear="no"/>
<itemref idref="book" linear="yes"/>
<itemref idref="toc" linear="no"/>
</spine>

[JSWolf]

What is your target audience for this ePub 3? There are very few apps/programs that will handle ePub 3. It might be a waste of time to work with ePub 3. Also, there is no indication that ADE currently will work with an ePub 3 with ePub 2 fallback.