Making a predefined layout for plotly in R - r

Question

I would like to make a predefined layout that I can use for my plot functions that I have created so as not to repeat myself everytime I make a plot. For example, I tried to do sth like the following which doesn't work and gives an error:
custom_layout <- function(){
plotly::layout(
xaxis = list(title = ""),
yaxis = list(title = ""),
title = list(text = title, y = 0.98)
)
}
plot_bar <- function(title, dt, x, y, fill){
plot_ly(dt, x = ~x, y = ~y, type = "bar",
color = ~ fill, split = ~ fill) %>%
custom_layout()}
plot_line <- function(title, dt, x, y, fill){
plot_ly(dt, x = ~x, y = ~y, type="scatter",
split = ~fill, mode="lines+markers") %>%
custom_layout()}
I call these 2 plotting functions multiple times in my code. I have also other predefined plotting functions like plot_line and plot_bar and I use the same layout for them as well but now manually adding the layout like in the following:
plot_bar <- function(title, dt, x, y, fill){
plot_ly(dt, x = ~x, y = ~y, type = "bar",
color = ~ fill, split = ~ fill) %>%
layout(
xaxis = list(title = ""),
yaxis = list(title = ""),
title = list(text = title, y = 0.98)
Ideally, I would like to define it like in the first scenario with a predefined layout that I could use later for every plotting function which is not working for me. Is there a way to do it with native plotly and not ggplot2?

Answer 1

You need to make the custom_layout() function take p as its first argument (just like layout() does).
library(tibble)
dt <- tibble(x=1:4, y=3:6, fill=1:4)
custom_layout <- function(p, title){
plotly::layout(p,
xaxis = list(title = ""),
yaxis = list(title = ""),
title = list(text = title, y = 0.98)
)
}
plot_bar <- function(title, dt, x, y, fill){
plot_ly(dt, x = ~x, y = ~y, type = "bar",
color = ~ fill, split = ~ fill) %>%
custom_layout(title=title)}
plot_bar(title="myplot", dt, "x", "y", "fill")