ggplot2 merge color and fill legends

Question

I want to merge two legends in ggplot2. I use the following code:

ggplot(dat_ribbon, aes(x = x)) +
  geom_ribbon(aes(ymin = ymin, ymax = ymax,
                       


        

Answer 1

You are not using ggplot2 according to its philosophy. That makes things difficult.

ggplot(dat_ribbon, aes(x = x)) +
  geom_ribbon(aes(ymin = ymin, ymax = ymax, group = group, fill = "test4 test5"), 
              alpha = 0.2) +
  geom_line(aes(y = y, color = "Test2"), data = dat_m) +
  geom_blank(data = data.frame(x = rep(5, 4), y = 0.5, 
                               group = c("test4 test5", "Test2", "test", "Test3")), 
             aes(y = y, color = group, fill = group)) +
  scale_color_manual(name = "combined legend",
                     values=c("test4 test5"= NA, "Test2" = "white", 
                              "test"="black", "Test3"="red")) + 
  scale_fill_manual(name = "combined legend",
                    values = c("test4 test5"= "dodgerblue4", 
                               "Test2" = NA, "test"=NA, "Test3"=NA))