Datagrid: multiple hilites

[David Bovill]

I've upgraded to the latest datagrid - fixes the add to end issue reported
earlier. So naturally that's led to another one :)

I want to allow the user to quickly select multiple lines of a form by
clicking on them - with "auto select" unless you hold down the command key.
I scripted a way to do that using the dgHilitedIndex:

command tweet_ToggleHilite
>    put the dgControl of me into dataGrid
>    if the dgProp ["auto hilite"] of dataGrid is false then
>       put the dgLine of me into myIndexNum
>       put the dgHilitedIndex of dataGrid into indexNums
>       set the wholematches to true
>       put itemOffset (myIndexNum, indexNums) into foundItem
>       if foundItem = 0 then
>          if indexNums is empty then
>             put myIndexNum into indexNums
>          else
>             put comma & myIndexNum after indexNums
>          end if
>       else -- already hilited
>          delete item foundItem of indexNums
>       end if
>       sort numeric items of indexNums
>
>       lock screen
>       put the dgControl of me into dataGrid
>       put the dgVScroll of dataGrid into someScroll
>       set the dgHilitedindex of dataGrid to indexNums
>       put indexNums
>       set the dgVScroll of dataGrid to someScroll
>       unlock screen
>    end if
> end tweet_ToggleHilite
>

However this script only works until, I start adding lines using "AddData".
Maybe there is a better way?