ggplot2填充和颜色映射图例

Question

I have a sample data frame with four variables and I'm trying to map h variable to fill and s variable to shape . Since my s variable can take only two values (either 'f' or 'u') I want to use geom_point 24 and 21 which can take fill and colour argument.

library(ggplot2)
h <- c(1,2,3,4,5)
x <- seq(1:5)
y <- c(1,3,3,5,5)
s <- c(rep('f',3),rep('u',2))
dt <- data.frame(h,x,y,s)

Ideally, my geom_point would have black outline and coloured fill . I can plot this with the below code and it produces this plot:

ggplot(dt, aes(x=y, y=x)) +  
    geom_point(mapping = aes(fill = factor(h), shape = s), size = 5) +
    scale_shape_manual(values = c(24, 21))

I cannot get legend to display coloured keys since colour of legend key is mapped to colour not to fill .

I can have coloured legend keys if I change my geom_point to 19 and 17 and map my h variable colour :

ggplot(dt, aes(x=y, y=x)) +  
    geom_point(mapping = aes(colour = factor(h), shape = s), size = 5) +
    scale_shape_manual(values = c(19, 17))

Legend is displayed with coloured keys but black outline on my points on plot is gone.

Is there any way to choose what is mapped on legend key ( fill or colour ) if I used both fill and colour for geom_point ?

Answer 1

ggplot(dt, aes(x=y, y=x)) +  
    geom_point(mapping = aes(fill = factor(h), shape = s), size = 5) +
    scale_shape_manual(values = c(24, 21)) +
    guides(fill=guide_legend(override.aes=list(shape=21)))

Above code produces this plot - exactly as I wanted, credits to bdemarest

fill mapped to legend