radarchart: Change background color

I want to change the background color of the radar chart. I don't see any argument that allow me to do this. Help?

Here's what I have so far:

structure(list(Acceptance = c(16, 4, 13), `Committed Action` = c(16, 
4, 11), Diffusion = c(16, 4, 7), `Present Moment` = c(16, 4, 
10), `Self as Context` = c(16, 4, 11), Values = c(16, 4, 12)), row.names = c(NA, 
-3L), class = c("tbl_df", "tbl", "data.frame"))

# DF Structure

Acceptance `Committed Action` Diffusion `Present Moment` `Self as Context` Values
       <dbl>              <dbl>     <dbl>            <dbl>             <dbl>  <dbl>
1         16                 16        16               16                16     16
2          4                  4         4                4                 4      4
3         13                 11         7               10                11     12

Graph:

radarchart(df, axistype=1,
           #custom polygon
           pcol="darkblue", pfcol=rgb(0.2,0.5,0.5,0.5), plwd=3,
           #custom the grid
           cglcol="grey50", cglty=1, axislabcol="black", caxislabels=seq(4,16,length.out = 5), 
           cglwd=2,
           #custom labels
           vlcex=1.8, calcex=1.8)

This is what I get:

I have tried:


g <- radarchart(df, axistype=1,
           #custom polygon
           pcol="darkblue", pfcol=rgb(0.2,0.5,0.5,0.5), plwd=3,
           #custom the grid
           cglcol="grey50", cglty=1, axislabcol="black", caxislabels=seq(4,16,length.out = 5), 
           cglwd=2,
           #custom labels
           vlcex=1.8, calcex=1.8) 

g + theme(panel.background = element_rect(fill = "lightgray"))

# Output: NULL

Is there no way to add background color?

Solution

If your question addresses the use of radarchart from the fmbs package, the first thing to note is that this produces a plot using base R graphics. Modifying the background using theme() won't work because g is not a ggplot object.

Option 1: add a background to the entire plotting area setting graphical parameters for plotting

library(fmsb)

par(bg = "lightgray")

fmsb::radarchart(df, axistype=1,
                #custom polygon
                pcol="darkblue", pfcol=rgb(0.2,0.5,0.5,0.5), plwd=3,
                #custom the grid
                cglcol="grey50", cglty=1, axislabcol="black", caxislabels=seq(4,16,length.out = 5), 
                cglwd=2, 
                #custom labels
                vlcex=1.8, calcex=1.8)

Option 2: If you want to use ggplot, you could install the ggradar package and produce your radar chart that way. It will look different but here's a start. https://github.com/ricardo-bion/ggradar

devtools::install_github("ricardo-bion/ggradar", 
                          dependencies = TRUE)
library(ggradar)
df<-df %>%
  as_tibble(rownames = "group")

# note that in the below I'm only selecting the third row of your dataframe
# this is to reproduce your plot above
ggradar(df[3,], grid.min = 4, grid.mid = 10, grid.max = 16,
        values.radar = c(4, 10, 16), 
        gridline.mid.colour = "grey",
        axis.label.size=4,
        axis.label.offset   = 1.1) + 
  theme(panel.background = element_rect(fill = "lightgray"))