R/gggap_legend.R

In gggap: Streamlined Creation of Segments on the Y-Axis of 'ggplot2' Plots

#' @title Add Legend to gggap()
#' @description Adds a legend to a gggap().
#' @param plot A 'ggplot2' plot.
#' @param margin Margins around the text.
#'
#' @return A legend-added picture
#'
#' @examples
#' library(ggplot2)
#' mtcars$gear <- factor(mtcars$gear)
#' bp <- ggplot(
#'   data = mtcars,
#'   aes(x = gear, fill = gear)
#' ) +
#' geom_bar() +
#' ggtitle("Number of Cars by Gears") +
#' xlab("Gears")
#' gggap(
#'   plot = bp,
#'   ylim = c(0, 16),
#'   segments = c(6, 8))
#' gggap_legend(
#'   plot = bp,
#'   margin = c(top = 1, right = 1, bottom = 1, left = 460)
#' )
#' @export
gggap_legend <- function(plot,
                         margin = c(
                           top = 200,
                           right = 200,
                           bottom = 200,
                           left = 200
                         )) {
  legend <- cowplot::get_legend(
    plot +
    theme(legend.box.margin = margin(margin))
  )
  grid::grid.draw(x = legend, recording = TRUE)
}