r - get list of colors used in a ggplot2 plot? -

possible duplicate:
how extract fill colours ggplot object?

in arbitrary ggplot plot,

p <- ggplot(data=plantgrowth, aes(x=group, y=weight, fill=group)) + geom_boxplot()

is there way extract code of colors used (i.e. variable named "values" modify command

p + scale_fill_manual(values=c("#999999", "#e69f00", "#56b4e9"))

) ?

i colors used in order modify one.

thank you,

françois

for discrete scale (with default setting scale_colour_hue) function hue_pal in package scales used. e.g., 3 factor levels:

r> library(scales) r> scales::hue_pal()(3) [1] "#f8766d" "#00ba38" "#619cff"

UV code