Remove legend elements of one specific geom: “show.legend = FALSE” does not do the job

Question

I have written an answer here and would like to improve it. What I would like to do is to remove the legend for geom_path but it is not working with show.

Answer 1

Another possibility (but more overall work) is to manually specify the colors for the arrows:

library(ggplot2)
library(tidyr)
library(dplyr)

ggplot2df <- read.table(text = "question y2015 y2016
q1 90 50
q2 80 60
q3 70 90
q4 90 60
q5 30 20", header = TRUE)

ggplot2df %>% 
  mutate(direction = ifelse(y2016 - y2015 > 0, "Up", "Down")) %>%
  gather(variable, value, -question, -direction) -> df

gg <- ggplot(df, aes(x=question, y = value, group = question)) 
gg <- gg + geom_point(aes(color=variable), size=4) 
gg <- gg + geom_path(color=c("red", "red", "green", rep("red", 4), "green", "red", "red"),
                     arrow=arrow(), show.legend=FALSE)  
gg