The above image shows List Box.
I want to set a variable when any of the week is selected.
Settings -> document properties -> triggers -> field event triggers - >on select
and add the action you need (external -> set variable)
you can define the variable so that when there is one or more weeks selected.........
=if(GetSelectedCount(WeekField) > 0, MaxString(WeekField))
adapr the function in bold to your need
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