Hi,
My first solution is incorrect ; with the second solution, I don't
understand why the first chapter is not numbered while the second is with
number 1.
Thanks.
Fabrice
\unexpanded\def\HeadTitle#1#2%
   {
     \FramedText{{\cap\labeltext{chapter}}\space#1
      \\
     \bfc#2}
   }

\unexpanded\def\processheadnumber#1%
   {\getmarking[chapternumber]}

 \setuphead
   [chapter]
   [style=\bfd,
    align={flushleft,broad},
    numbercommand=\processheadnumber,
    command=\HeadTitle]


\starttext
\startchapter [title={La récurrence}]
  \startsection[title={Le principe de récurrence}]
     \dorecurse{10}{\input knuth}
  \stopsection
  \startsection[title={Le raisonement par récurrence}]
      \dorecurse{10}{\input knuth}
  \stopsection
  \startsection[title={Récurrences fortes}]
      \dorecurse{10}{\input knuth}
  \stopsection
   \startsection[title={Exercices corrigés}]
      \dorecurse{10}{\input knuth}
  \stopsection
\stopchapter
\startchapter [title=Combinatoire-Dénombrement]
    \dorecurse{10}{\input knuth}
\stopchapter

\stoptext



Le lun. 12 juil. 2021 à 16:32, Fabrice Couvreur <fabrice1.couvreur@gmail.com>
a écrit :

> Hi,
> For my book, the header for each chapter should be like the attached image. I
> don't know if I am using the best method, but the result looks like what I
> want. Nevertheless, I am having some problems :
> 1. the header appears on each page ;
> 2. the title of the chapter should not appear in the body of the text.
> Thanks for your help.
> Fabrice
>
> \definecolor[MyColorA][r=0.8784, g=0.8784, b=0.8784]
> \defineframedtext
>           [FramedText]
>           [
>             offset=0.6em,
>             style=,
>             toffset=\lineheight,
>             background=color,
>             backgroundcolor=MyColorA,
>             foregroundstyle={\switchtobodyfont[11pt]},
>             align={left, broad},
>             frame=off,
>             width=\textwidth,
>           ]
>
>
> \setuplabeltext
>      [en]
>      [chapter=CHAPITRE]
>
> \setuphead
>    [chapter]
>    [bodypartlabel=]
>
>
> \startsetups [header]
>      \labeltext{chapter} \getmarking[chapternumber]
> \stopsetups
>
> \setupheadertexts
>   []
>   [{\FramedText{{\cap\labeltext{chapter}\space\getmarking[chapternumber]}
>      \\
>     \bfc\getmarking[chapter]}}]
>   []
>   [\FramedText{{\cap\labeltext{chapter}\space \getmarking[chapternumber]}
>      \\
>    \bfc\getmarking[chapter]}]
>
>
> \setuppagenumbering
>      [alternative=doublesided,location=]
> \starttext
> \startchapter [title=La récurrence]
>   \startsection[title={Le principe de récurrence}]
>      \dorecurse{10}{\input knuth}
>   \stopsection
>   \startsection[title={Le raisonement par récurrence}]
>       \dorecurse{10}{\input knuth}
>   \stopsection
>   \startsection[title={Récurrences fortes}]
>       \dorecurse{10}{\input knuth}
>   \stopsection
>    \startsection[title={Exercices corrigés}]
>       \dorecurse{10}{\input knuth}
>   \stopsection
> \stopchapter
> \startchapter [title=Combinatoire-Dénombrement]
>     \dorecurse{10}{\input knuth}
> \stopchapter
>
> \stoptext[image: pied_3.png]
>
>