Control bar border (color) thickness with ggplot2 stroke

Question

Is it possible to use the stroke argument introduced with ggplot2 2.0 to adjust the thickness of borders around bars? If not, is there a way to control bar-border

Answer 1

well as I suggested by the OP, I will just recopy my comment as an answer.

you just need to set size in your geom_bar() expression:

geom_bar(stat = "identity", aes(fill = "transparent", size = ifelse(factor2 == "A", 2, 1)), size=2)