rgg.R

#' @title Remove and replace ggplot2 layers.
#' @export
#' @description
#' Removes specified layers from a ggplot object and gives
#' the option to replace them with a new layer. This layer can be either
#' a geom object created from regular ggplot functions or an output from
#' the ggedit gadget.
#' In the latter case the layers are found in the updatedLayers object in
#' the ggedit output.
#' @param p ggplot2 plot object
#' @param oldGeom character string of the name of the layer to remove
#' @param oldGeomIdx numeric of which index of OldGeom to remove (default is 1)
#' @param newLayer ggplot layer or list of layers
#' @examples
#' p <- ggplot2::ggplot(iris,ggplot2::aes(x =Sepal.Length,y=Sepal.Width))
#'
#' p <- p+ggplot2::geom_point(ggplot2::aes(colour=Species))+ggplot2::geom_line()
#'
#' p
#'
#' p |> rgg('point',1)
#'
#' if( interactive() ){
#' x <- ggedit(p)
#' pnew <- p |> rgg('point',1,x$updatedLayers[[1]])
#' pnew
#' }
#' @import ggplot2
rgg <- function(p, oldGeom, oldGeomIdx=1, newLayer=NULL) {
  if (is.null(oldGeom)) return(p)
  p <- plot_clone(p)
  p <- remove_geom(p = p, geom = oldGeom, idx = oldGeomIdx) + newLayer
  set_last_plot(p)
  p
}