Bug or feature in "Edit Table Of Contents"

[jd1004]

In Epub3, using Tools > Table Of Contents > Edit Table Of Contents and clicking "OK" without making any edits changes the file toc.xhtml. The formatted entries that are actually displayed in the ebook (most nav entries are hidden) change to a numbered list of links without formatting:

OLD:

<body>
  <nav epub:type="toc" id="toc" role="doc-toc">
    <h1 class="toc-title" id="abc">CONTENTS</h1>

    <ol class="none" epub:type="list">
      <li class="toc-front"><a href="cover.xhtml"><span class="toc_entry">COVER</span></a></li>

NEW:

<body>
  <nav epub:type="toc" id="toc" role="doc-toc">
    <h1>Table of Contents</h1>
    <ol>
      <li>
        <a href="cover.xhtml">COVER</a>
      </li>

So, editing the toc via the build-in function destroys the toc formatting.

Is that a bug or a feature?

[KevinH]

Editing the TOC, unless you hit Cancel will create a new standard Sigil format TOC.

It sounds like you hit OK which causes the rebuild. It does not matter if you changed anything or not, Sigil takes the information given by the Edit TOC and recreates the TOC from it. That is expected behaviour.

It also sounds as if you are now missing a link to a css stylesheet for that nav that controls the numbering or not. A standard Sigil format Nav typically includes its own linked stylesheet. Simply editing that newly created stylesheet will enable you to control the numbering and what gets hidden.

FYI, people often add and remove headings and chapters while editing, and so it is often easier to simply generate the entire TOC using Sigil tools once near the end, editing it as needed in the TOC editor, or editing the Nav directly in CodeView before going final. Editing a custom TOC not originally generated by Sigil may not be what you want, especially if you did not Cancel or exit that Dialog.

If you do not like that change, assuming you have created a Checkpoint (which is always a good idea) you can easily revert.

[jd1004]

I think the trouble is that the file toc.xhtml serves double duty as the nav file and as the visible table of contents.

I can fix that by making a copy of the file. That copy is then unaffected by a recreation of the toc and retains its formatting.

The trouble with that particular epub3 is that there are lots of links to the original toc.xhtml which all get broken as soon as I edit the toc via the menu because all the ids are lost.

Also, there is a toc.ncx file in addition to the toc.xhtml "nav" file. I'm not sure what that's about. I thought the ncx file is for epub2 only?

[DiapDealer]

Originally Posted by jd1004

Also, there is a toc.ncx file in addition to the toc.xhtml "nav" file. I'm not sure what that's about. I thought the ncx file is for epub2 only?

The toc.ncx can be safely deleted from an EPUB3, but many leave it in for backward compatibility with EPUB2 reading systems. For basic things like novels, most vanilla EPUB3s can be read in EPUB2 reading systems just fine (unless the toc.ncx is missing).

[KevinH]

And you can rename the nav to anything. It need not be named nav.xhtml nor toc.xml. Start with a fresh copy, In Sigil, duplicate toc.xhtml and create a toc2.xhtml. Rename the existing toc.xhtml to nav.xhtml.

I think if done in that order, all external links to the original toc.xhtml should all be auto updated to point to the nav.html. Edit and rename the toc2.xhtml till your heart is content.

Worth a try at least.

[KevinH]

Alternatively you could use Sigil to create an HTML toc from your current nav, and then edit that.

[jd1004]

Thanks guys!

I created a copy of the NAV file, renamed that to contents.xhtml, edited "contents" and changed all the links in the epub from "nav" to "contents". That did the trick.

For the extraneous toc.ncx I also kept, EpubCheck gives me the message

OEBPS/toc.ncx,140,4833,Col: 48: ERROR(RSC-007): Referenced resource "OEBPS/Text/discover-page.xhtml" could not be found in the EPUB.

Of course, since this is an Epub3 file, deleting the file "discover-page.xhtml" will only edit the NAV file, not the NCX file, but I think I can live with that error check message. Manually deleting the file entry from toc.ncx unfortunately only channges the error message, because then there is a gap in the internal numbering:

OEBPS/toc.ncx,136,4710,Col: 48: ERROR(RSC-005): Error while parsing file: playOrder sequence has gaps

Would it be possible to update both the NAV and the NCX file in an Epub3 if both files are present?

Cheers and keep up the good work!

[jd1004]

P.S.: Good thing I kept the toc.ncx. My Tolino Vision 4 HD is displaying that instead of the NAV file.

[KevinH]

Go to Sigil Tools menu and from it select the Epub3 Tools menu. These are the epub3 specific tools to delete the guide and ncx. There is another tool there to recreate the guide and ncx based in the current nav. So no need to manually edit the ncx. There are also tools to update Manifest properties.

So once you are happy with the nav, use the epub3 tools to delete the guide and ncx, then the epub3 tool to create the guide and ncx based in your nav so that they match.

Then as a last step, run the Update Manifest properties tool just to be safe.