How is the index created in an ebook?
The TOC index (Table of Content) is a file inside the ebook that allows the user to navigate easily between its various parts. The TOC is visible to the user through the "INDEX" function that is available in all of the reading apps.
In the image below you can see an example of the TOC link in Apple iBooks:
In order to be used correctly and to offer a good user experience, an ebook must have a complete and accurate TOC index, regardless of the application used for reading.
The presence of the TOC file in the ePub is also crucial for the proper processing of the ebook file from certain ebook stores, such as Amazon, Apple iBooks, or Kobo.
How to get TOC index in reflowable ePUBs
The Write tool automatically generates the TOC file by creating an Index Lemma for each part in which the ebook reflowable is divided: Part, Section, Chapter. To get a reflowable ePub with an accurate index, simply complete the "TITLE" field for each part of the ebook you’ve created.
How to get the TOC index in ePub3 FXL
You can get FXL ePub3’s by importing a PDF file.
If you import a PDF with bookmarks, Write will recognize them and create index headings starting from those bookmarks.
If your PDF does not have a bookmark, you will have to provide Write with accurate information to create the TOC by adding the title of the chapter in the title field on the page where it starts.
While in the ePub2 reflowable the index is generated and therefore is a visible "page" of the ebook, in the FXL the index does not appear as a real book page so it can only be displayed by clicking on the specific button of the e-reader (with some readers, it opens as a pop-up).