PopAsync pass result

Hi,

I use navigation page to navigate from page A to page B.
Page B only contains a listview with values. When a users clicks an item in the listview. The page is poped.
Now when popping page B, I would like for page A to receive the value selected in Page B.

In short:
1) NavigationPage
2) Navigate from page A to page B
3) Select value in Page B
4) return selected value from page B to page A

Preferably I would like to avoid a static variable!

Thanks in advance!