Does Digital Edition support fallback for epub?

[sfan]

Hi,

I am playing around with epub format those days.

I tried to embed non-standard resource files in the package and use fallback to display the alternative of those files. But seems like it didn't work.

I did a litter search, and found someone had similar problem:
http://www.idpf.org/forums/viewtopic...41399c30b40ec6

No body answered the post.

Is there anyone knowing if the fallback is supported by current Digital Edition (1.5)?

Thanks,
sfan

[Hadrien]

Very interesting question. Which kind of non-standard resources did you tried to embed in the OPF file ?

You should ask such questions to the ePub group: http://groups.yahoo.com/group/epub-community/

[sfan]

Thank you for the reply.

I just did a simple experiment with just XML files.

In opf file, I defined:
<item id="titlepage" href="title.xml" media-type="application/xhtml+xml"/>
<item id="note" href="note.xml" media-type="application/xhtml+xml"/>
<item id="kml" href="kml_sample.kml" media-type="application/google+kml" fallback="titlepage"/>

In note.xml, I added a link like this:
<p><a href="kml_sample.kml">KML</a></p>

From my understanding, if fallback is supported, when the KML link is clicked, reader app should jump to title.xml. DE displayed KML as a link, but when I clicked, nothing happened.

[Hadrien]

Have you tried the item with "kml" as an id in the spine first ?

[sfan]

Originally Posted by Hadrien

Have you tried the item with "kml" as an id in the spine first ?

I tried, but still nothing happened.

I attached the epub file I created.

[Jon Noring]

Originally Posted by sfan

I just did a simple experiment with just XML files.

In opf file, I defined:
<item id="titlepage" href="title.xml" media-type="application/xhtml+xml"/>
<item id="note" href="note.xml" media-type="application/xhtml+xml"/>
<item id="kml" href="kml_sample.kml" media-type="application/google+kml" fallback="titlepage"/>

In note.xml, I added a link like this:
<p><a href="kml_sample.kml">KML</a></p>

From my understanding, if fallback is supported, when the KML link is clicked, reader app should jump to title.xml. DE displayed KML as a link, but when I clicked, nothing happened.

It is important to refer to the OPF Specification which defines the mechanism to assign fallbacks. You will need to add, for example, the 'fallback' attribute, and do it as specified.

Good luck!

[Hadrien]

Here's the example from the spec:

<manifest>
<item id="item1"
href="FunDoc.txt"
media-type="text/plain"
fallback="fall1" />
<item id="fall1" fallback="fall2"
href="FunDoc.pdf"
media-type="application/pdf" />
<item id="fall2"
href="FunDoc.html"
media-type="application/xhtml+xml" />
<item ...>
</manifest>

It's pretty late in Paris (almost 2am), haven't tried anything too fancy yet but I modified the fallback.epub, tried a link in the NCX or adding kml to the spine and it didn't work.

[sfan]

Originally Posted by Jon Noring

It is important to refer to the OPF Specification which defines the mechanism to assign fallbacks. You will need to add, for example, the 'fallback' attribute, and do it as specified.

Good luck!

I followed the spec by adding fallback attribute to the kml item:

<item id="kml" href="kml_sample.kml" media-type="application/google+kml" fallback="titlepage"/>

Is there anything I missed?

[sfan]

Originally Posted by Hadrien

Here's the example from the spec:


It's pretty late in Paris (almost 2am), haven't tried anything too fancy yet but I modified the fallback.epub, tried a link in the NCX or adding kml to the spine and it didn't work.

Have a sweet sleep!

[Jon Noring]

Hmmm, after posting my first comment, I opened up the example ePub with the test 'fallback'. At cursory glance it looks like you've done it right.

It is entirely possible that Adobe DE 1.5 does not yet support the fallback mechanism, just as it doesn't support alternative NCX navlists.