Is it possible to change order of items in an invoice formular?

Hi guys,

there is a need for changing the order of the items in an invoice dependent on some attribut.

Without any change, the invoice just prints all items ordered py Positionnumber (e.g. 10,20,30,40)

I do need a functionality, which does not print all items in that order, but in another (e.g. 30,10,20,40). This order will depend on an additional attribute which is bound to an item, so if the attributesvalue is true, this item has to be the first one.

It is not possible that tow items have set this attribute to true. It is always at most one.

How can I work on this using FOrmCalc or Javascript in Adobe Livecycle Designer?

Any suggestions?

Thanks in advance...

Regards

E.T.