I did something similar in VB6 a few years ago. I had to use a font that used the same amount of space no matter what the letter. i.e. most fonts use less width for letters like 'i' so makes calculating the length very difficult.
Basically, in VB I found out how many characters the element could hold, find out how many characters each of the two items in each column used and then fill in the middle with spaces " ". Worked well for that instance but will be very different on android as the listview could show different amount of characters dipending on device loaded on.
I would either, as Erel says, use 2 listviews and link their positions in code, Or use a scrollview with some labels.