Hi Wolfgang,
Pablo's solution works, but I tried yours without success. Here are the
main lines of my project

%%%% begin product
\startproduct[terminale-manual]

\project[terminale-environment]

\startdocument

\startfrontmatter
...
\stopfrontmatter

\startbodymatter
\component[terminale_recurrence]
...
\stopbodymatter

\stopdocument

\stopproduct
%%%% end product

%%%% begin project
\startproject[terminale-environment]

\environment[terminale-style]
 ...
\stopproject
%%%% end project

%%%% begin component
\project[terminale-environment]

\startcomponent[terminale_recurrence]
...
\endcomponent
%%%% end component

%%%% begin environment
\startenvironment[terminale-style]
...
\startsetups [section:chapter]

\setuphead
   [chapter]
   [align=flushright,
    textcommand=\groupedcommand{\blank[medium]}{},
    numbercolor=darkgray,
    textstyle=ChapterTextStyle,
    numberstyle=ChapterNumberStyle,
    before=\startChapterFrame,
    after=\stopChapterFrame,
    header=high]

\stopsetups

\startsectionblockenvironment [bodypart]
     \directsetup{section:chapter}
\stopsectionblockenvironment

\doifmode{*component}{\directsetup{section:chapter}}

...
\endenvironment
%%%% end environment

Le dim. 15 août 2021 à 19:03, Wolfgang Schuster via ntg-context <
ntg-context@ntg.nl> a écrit :

> Pablo Rodriguez via ntg-context schrieb am 15.08.2021 um 18:33:
> > On 8/15/21 6:02 PM, Fabrice Couvreur via ntg-context wrote:
> >> A small note : this method works if I compile the project but if I
> >> compile only one chapter, the header no longer appears.
> > Hi Fabrice,
> >
> > I have never used projects and chapters (or whatever the right name is).
> >
> > I’m not sure I get what you’re experiencing: with a single chapter, do
> > you have the fancy layout or not?
> >
> > It would make sense that the fancy chapter doesn’t appear only compiling
> > a chapter. I guess there is no \startbodymatter...\stopbodymatter
> > wrapping it.
> >
> > Another approach would be:
> >
> > [...]
>
> Setting values for \title is a way to avoid the chapter setup for the
> table of contents etc.
> but there is a way to set values which are used only when you process a
> component file.
>
> To make it work one has to load the environment file after
> \startcomponent because you
> can use the *component mode to check whether the parent file is a
> product or a component.
>
> %%%% begin product
> \startproduct [*]
>
> \environment [...]
>
> \startfrontmatter
> ...
> \stopfrontmatter
>
> \startbodymatter
> \component [...]
> \stopbodymatter
>
> \stopproduct
> %%%% end product
>
> %%%% begin component
> \startcomponent [*]
>
> \environment [...]
>
> ...
>
> \stopcomponent
> %%%% end component
>
> %%%% begin environment
> \startenvironment [*]
>
> \startsetups [section:chapter]
>
>      \setuphead
>          [chapter]
>          [...]
>
> \stopsetups
>
> \startsectionblockenvironment [bodypart]
>      \directsetup{section:chapter}
> \stopsectionblockenvironment
>
> \doifmode{*component}{\directsetup{section:chapter}}
>
> \stopenvironment
> %%%% end environment
>
> Wolfgang
>
>
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