ID cross-reference needs to cite other volume

[Nedlaw]

Using ID17/2022 on Win10

Hi. I have used ID to produce a 550-page book for a client, and the client now wants it divided into two volumes. Both volumes are loaded with Xrefs. I'm looking for a method that allows me to create a cross-reference that refers to the volume (vol 1 or vol 2) in addition to the chapter or appendix number and the title (and page #) of the target.

I currently have the Xrefs set up so that I can separately point to Chapter X or Appendix Y followed by the title of the chapter or appendix (if needed) because the titles are both the same style -- only the numbered chapter style and numbered appendix styles are individually defined. Thus, I can say "See Chapter X" without constantly saying "See Chapter X: Long Title, on page 238."

 Here's where I brake to a halt: Where would I put the volume number so that I can refer to it via an Xref definition?

For example, I can create "See <chapter num>: <chapter title>, on page <pagenum>" and get "See Chapter 6: An Excellent Title, on page 257." What I need to be able to say (I think) is "See <chapter num>: <chapter title>, in Volume <volnum>, page <pagenum>," and get "See Chapter 6: An Excellent Title, in Volume 2, page 283." My problem is I don't know where to stash or how to refer to that "<volnum>" volume number. I am guessing that the volumn number needs to be part of each component chapter/appendix file so that I can refer to it in the Xref... but where? Is this a job for a text variable?

As always, help from the community is appreciated.

-j

[Nedlaw · Accepted solution]

I'll answer my own question since the community seems quiet on the matter.

On the title page of the book (in a file called title_page) there are the words Volume One with the paragraph style paragraph_volume_number. Not coincidentally, the other volume has a similarly styled paragraph with the text Volume Two. All files for both books are in the same directory so they can be found. There are two different book files.

I added a text marker to the volumn number paragraph.

Then, as part of my cross reference, I point to the title page file and the text anchor txtVolNum, and in comes the content of the paragraph -- volumn one or volume two as needed. 

Note that I'm constructing the Xrefs from parts, so the page number of the text anchor doesn't matter, only its contents. What I did not try was to add the text anchor volume one/volume two to each file in the book (probably colored whire to hide it). This would allow me to create a single Xref from parts all at once. But -- as I mentioned in my original post -- doing the Xref in parts allows me to say "See Chapter 3, 'Big Title' on page 46" or "See Chapter 3" or (now) "See Chapter 3, 'Big Title' in Volume Two on page 300"...