OS-independent way to select directory interactively in R

Question

I would like users to be able to select a directory interactively in R. The solution needs to work on different platforms (at least on Linux, Windows and Mac machines that have

Answer 1

Here is a simple directory navigation menu (using menu{utils}):

d=1
while(d != 0) {
  a = getwd()
  a = strsplit(a, "/")
  a = unlist(a)
  b = list.dirs(recursive = F, full.names = F)
  c = paste("..", a[length(a) - 1], a[length(a)], sep = "/")
  d = menu(c("..", b), title = c, graphics = T)
  if(d==1){
    e=paste(paste(a[1:(length(a)-1)],collapse = '/',sep = ''),'/',sep = '')
    #print(e)
    setwd(e)
  }else{
    e=paste(paste(a,collapse = '/',sep = ''),'/',b[d-1],sep='')
    #print(e)
    setwd(e)
  }
}

Note: I did not (yet) test it under different systems. Here is what the documentation says:

If graphics = TRUE and a windowing system is available (Windows, macOS or X11 via Tcl/Tk) a listbox widget is used, otherwise a text menu. It is an error to use menu in a non-interactive session.

One limitation: The title = can only be a single line.