Spinbox in "R" tcltk2

Question

I created a spinbox in a "R" GUI by means of the "tcltk2" library

   my_ratio <- tk2spinbox(my_window, from = 1, to = 10, increment = 1)

How can I give the value of the selection to a "R" numeric variable?

Answer 1

Philippe Grosjean, the author of tcltk2, gently showed me how to do it with the following snippet:

library(tcltk2)
my_window <- tktoplevel()

spin_value <- tclVar(3)
my_ratio <- tk2spinbox(my_window, from = 1, to = 10, increment = 0.1, textvariable = spin_value, format = "%5.1f", width = 10)
tkgrid(tk2label(my_window, text = "Ratio:"), my_ratio, padx = 10, pady = c(10, 5))

on_ok <- function() {
  val <- as.numeric(tclvalue(spin_value))
  tkdestroy(my_window)
  cat("The ratio is:", val, "\n")
}
my_but_ok <- tk2button(my_window, text = "OK", width = -6, command = on_ok)
tkgrid(my_but_ok, columnspan = 2, padx = 10, pady = c(5, 15))

tkfocus(my_window)