Re: Labels in beamer new exporter

[Nicolas Goaziou <n.goaziou@gmail.com>]

Hello,

Fabrice Popineau <fabrice.popineau@supelec.fr> writes:

> I'm trying to reference a slide using the beamer new exporter.
> Each frame gets its own label automagically (sec-#-##).
> Is there a way to reference those labels later on ? Using emacs-lisp ?
> Or ?

You refer to these labels when you create an internal link (fuzzy, by
custom-id, or by id) to the headline. So the idea is that you don't have
to bother with label's name.

Unfortunately, there's one limitation for now: it isn't possible to
specify an overlay for the target. For example:

--8<---------------cut here---------------start------------->8---
#+OPTIONS: H:1

* Frame 1
  :PROPERTIES:
  :CUSTOM_ID: frame1
  :END:

  #+ATTR_BEAMER: :overlay "+-"
  - item 1
  - item 2

* Frame 2

  [[*Frame 1][Link to first frame]]                     (1)

  [[#frame1][@@e-beamer:<2>@@Link to first frame]]       (2)
--8<---------------cut here---------------end--------------->8---

(1) will produce \hyperlink{sec-1}{Link to first frame}

(2) will produce \hyperlink<2>{sec-1}{Link to first frame}   (*)

At the moment, there's no way to produce:

  \hyperlink{sec-1<2>}{Link to first frame, second overlay}  (+)

I may swap the export-snippet usage in second case, if (*) is less
useful than (+).

Note that I hardly, if ever, use links in my presentations so
`org-e-beamer-link' is probably sub-optimal.

> I tried another way to solve my problem and wanted to define my own label
> on a frame :
>
> ** My frame titles                     :B_frame:
> :PROPERTIES:
> :BEAMER_opt: label=tcs
> :BEAMER_env: frame
> :END:
>
> Unfortunately, the new latex/beamer exporter does not seem to check that
> the user may have wanted to put his/her
> own label on a frame and it adds its own label to the user defined one.
> It is not that difficult to patch org-e-beamer--format-frame to avoid
> adding label when the user provides its own, but is it
> the right thing to do ?

Considering the remark above, I'm don't think that's the best way to
handle the problem. On the other hand, "label" is an option and should
be treated as such (that is, an user should be able to provide its own
value for it). It is implemented now.


Regards,

-- 
Nicolas Goaziou