Colors lost in legend when using scale_shape_manual

Question

I am trying to plot points using filled shapes from position 21 of the shapes.

d <- data.frame(expand.grid(a=letters[1:4],
      b=factor(1:2)), y=rnorm(8         


        

Answer 1

For some reason, the fill legend defaults to shape symbol 1 (solid circle), so it shows the color rather than the fill aesthetic. Add this to the ggplot command:

  + guides(fill=guide_legend(override.aes=list(shape=21)))