ggplot - plot only the colourbar

Question

I wish to plot only the colourbar, if possible at the center of the window, like this :

One example where I can't remove the points, axis and background.

library("ggplot2")
library("viridis")    

df <- data.frame(x = c(1,2,3,4,5,6), y = c(7,4,9,2,6,7))

ggplot(data = df, aes(x = x, y = y, colour = y)) + 
  geom_point() +
  scale_color_viridis()

Answer 1

The package ggpubr has a function for exactly this need.

df <- data.frame(x = c(1,2,3,4,5,6), y = c(7,4,9,2,6,7))

p <- ggplot(data = df, aes(x = x, y = y, colour = y)) + 
  geom_point() +
  scale_color_viridis() +
  theme_minimal()

# ggpubr does this for you
library(ggpubr)
leg <- get_legend(p)
as_ggplot(leg)