Hey there,

the code that you're using won't work with \item command.
Use the \startitem ... \stopitem command pair instead.

Another way to get itemizations in columns is to simply place one 
itemizeation per column:

\starttext

   two columns:

   \startcolumns[n=2]

     \startitemize[packed]
       \startitem
         one
       \stopitem
       \startitem
         two
       \stopitem
     \stopitemize

     \column

     \startitemize[packed]
       \startitem
         one
       \stopitem
       \startitem
         two
       \stopitem
     \stopitemize

   \stopcolumns

   \blank[big]

   three columns:

   \startcolumns[n=3]

     \startitemize[packed]
       \startitem
         one
       \stopitem
       \startitem
         two
       \stopitem
     \stopitemize

     \column

     \startitemize[packed]
       \startitem
         one
       \stopitem
       \startitem
         two
       \stopitem
     \stopitemize

     \column

     \startitemize[packed]
       \startitem
         one
       \stopitem
       \startitem
         two
       \stopitem
     \stopitemize

   \stopcolumns

\stoptext


Cheers



Am 30/12/2017 um 10:18 schrieb Fabrice Couvreur:
> Hello,
> How to modify the code for an enumeration on three columns in a column ?
> Thank you
> Fabrice
>
>
> \definemixedcolumns
>   [Mycolumns]
>   [
>     n=2,
>     separator=rule,
>     rulecolor=,
>     balance=,
>     grid=strut,
>   ]
>
> \setupalign[verytolerant,stretch,hanging]
>
> \setuppapersize[A4,landscape]
> \setupinteractionscreen[option=landscape]
>
> \starttext
> \startMycolumns
> \startitemize[n]
>   \item
>   \item
> \blank
> \startitemize[a,columns,three,joinedup]
> \item
> \item
> \item
> \stopitemize
> \stopitemize
> \stopMycolumns
> \stoptext
>
>
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