ConTeXt: Proper way to place enumerations in margins

Question

Is there a proper way to place and center enumerations in (outer)margin that

\defineenumeration[MyEnumeration][...]
\inmargin{
  \startMyEnumeration
    ...
  \stopMyEnumeration
}

or

\defineenumeration[MyEnumeration][...]
\inouter{
  \startMyEnumeration
    ...
  \stopMyEnumeration
}

Even that have some issues like not centering enumerations on doubleside: when rightside is good, leftside is on the page edge.

I tried to use alternative=margin, margin=yes and to play around with each enumeration properties but nothing seems to work.

I also tried to use \setupmargindata like in this link and all kinds of margins commands like here or here but I could not find a way to do what I want.

Answer 1

You can use the userdata environment to store the content for your enumeration in a buffer.

To place the enumeration together with the stored content in the margin you have to create a new alternative for the userdata environment. In the new alternative you can use the \margindata (or \inouter etc.) command to put the enumeration together with the content in the desired margin.

Below is a example for this method

\defineenumeration
  [MyEnumeration]
  [alternative=top,
   before=,
   after=,
   inbetween=,
   title=yes,
   text=Enum.]

\defineuserdataalternative
  [enumeration]
  [renderingsetup=enumeration:margin]

\startsetups[enumeration:margin]
  \margindata
    [inouter]
    {\startMyEnumeration[title=\userdataparameter{title},reference=\userdataparameter{reference}]
     \getinlineuserdata
     \stopMyEnumeration}
\stopsetups

\defineuserdata [Enumeration] [alternative=enumeration]

\setuplayout
  [width=10cm,
   rightmargin=6cm]

\starttext

\input tufte
\startuserdata [Enumeration] [title={Jojo Mayer}]
\input jojomayer
\stopuserdata
\input zapf

\stoptext

which results in the following output