[✓] Open/close cell groups in a presentation?

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 Dear Community,A newbie question: I've seen many times in Mathematica presentations that a neat, horizontal double chevron is used to open up and close parts of the notebook during presentations. This is very handy to present or hide information in a presentation. How this is done? I tried to search for the help, but got no acceptable results.tx for the kind answer in advance best regards Andras
5 months ago
7 Replies
 Murray Eisenberg 1 Vote As a start at an answer, you want to use the Option Inspector to enable the ShowGroupOpener option for the Selected Notebook. To use the Option Inspector, from the main Mathematica menu select Format > Option Inspector. In the new Option Inspector window that pops up, you see 3 fields across the top. In the leftmost field, select "Selected Notebook" instead of the default "Selection"; leave the middle field as is, "by category"; in the right field type "group opener". In the resulting tree of options shown below that, check the ShowGroupOpener option. See also However, I no longer remember how to change what symbol is used for the GroupOpener. This may involve editing the Stylesheet being used, but offhand I don't see how.
5 months ago
 Dear Murray,Thank you very much. I'll try this.best regardsAndras
5 months ago
 I mean this. I've found a good example on youtube:https://www.youtube.com/watch?v=lczqhcnVQ8cAfter 50s its visible how easy it is to show and hide content in a presentation. How this is done?Any help is gratefully appreciated.best regardsAndras
5 months ago
 That screen-shot video seems to be using precisely the GroupOpener that I described in my earlier response.