Hiding a slide

[Juanvvc]

Sometimes, I'd want to hide a slide from a presentation without removing it, for future references or just change slightly a presentation depending on the audience.

I know I could comment the slide using <!-- -->, but it would involve commenting in / out all extra slides every time.

Is there any way to hide slides in Marp?

I'm thinking about something like this, i.e., using a custom CSS class:

<style>
    .extra-slide { display: none}
</style>

# Normal slide

Text

---

# Hidden slide
<!-- _class: extra-slide -->

Text

---

# Normal slide

Text

This class hides the slide... using a black screen when it is the time of showing that slide.

Is there any chance that navigating the presentation using right/left keys would jump over these hidden slides?

Extra point if navigating with (for example) SHIFT+right/left keys do show these extra slides, in case someone has a question involving them

It is OK for me if the pagination jumps from slide number 3 to 5, for example, showing that there is an extra slide there.

[yhatt]

We have thought using HTML comment is enough to hide a slide.

Even so, I think that switching visibillity of the slide for navigation is a common case and valuable (e.g. Slide visibillity in reveal.js). If received many requests, we will consider to implement in Marpit framework.

FYI: Setting display: none is just meaning the slide is not visible, and not meaning to skip navigation. (Marp slides can be avilable for any other purpose than presentation on the stage so a style should not make a specific meaning as much as possible).

[undergroundwires]

Looking forward to have this in the framework. It's one of the core features that helps with reusable (context-switchable) slides by those who often do presentations.

HTML comments do not work when there are speaker notes or other _class directives and similar in the slide.

[tsaquet]

Hello @Juanvvc ! I need to do the same thing, did you find a way to do what you need ? Thank you :)

[Juanvvc]

Hello Thomas, I'm afraid I didn't find a solution, but having the possibility of using "hidden / extra slides" is a feature I would be very interested in, for the academia. Extra slides with additional explanations or details is very useful for the students. Also, I would also appreciate the possibility of showing these extra slides, during the lecture, if necessary. I believe the best option is capturing the event en JavaScript. For example, sending two "next slide" events if the next slide is "hidden", except if the shift key is clicked. I've not explored this possibility yet. Regards

…

On Wed, Aug 10, 2022, 16:16 Thomas Saquet ***@***.***> wrote: Hello @Juanvvc <https://github.com/Juanvvc> ! I need to do the same thing, did you find a way to do what you need ? Thank you :) — Reply to this email directly, view it on GitHub <#162 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AAFHBRHSVWJTNHYCH3RJTTTVYO2TXANCNFSM5DXPI5MQ> . You are receiving this because you were mentioned.Message ID: ***@***.***>

[tsaquet]

Hello Juan,

Thank you for your answer. I upvoted the request, I hope it will be added to the roadmap :)

I needed this feature to share groups of slides between decks and being able to hide some slides in the group.

To solve my problem I wrote a golang program that takes a json file describing which slides I need in a deck as input and generates an input .md file for Marp. For now it will be enough !

[yhatt]

Often overlooked but the idea can realize with a relatively simple Marp plugin, as you can see from better-for-plugin label of this thread. This is a plugin example to add hide local directive support into Marp: https://gist.github.com/yhatt/13a9f52c96821ae34c3de5f732f305df

We have hoped Marp community's someone passionate about the idea is going to make a Marp plugin, publish to npm, and maintain. If so, users who want an extended directive would be able to try it in Marp CLI and Node.js ecosystem easily.

Marp team could like to keep simple and smart core. We have thought just using HTML comment <!-- --> to hide slides is better, also in the view of CommonMark compatibility. So the extended syntax should be a community's plugin until verified its usefulness in widely.
https://github.com/marp-team/.github/blob/master/CONTRIBUTING.md#before-adding-new-feature

[tsaquet]

This works very well, thanks a lot ! Indeed, it would be great if someone could make a maintained plug-in as you suggested. I can't, I don't know the ecosystem (npm, node & co) and reading your code I realize that someone already knowing marp is needed.
Meanwhile, what you did can be very helpful to people asking for it, I hope they'll find this discussion !