search for: myglobalvar

I have any problem with my code. I build a small GUI in R with tcltk package. the proolem is I don't understand how to make a variable value can be read by R from a function. the variable value can only read if it's called via tcltk widgets and pass it to another function. i think the point is the variable must be set as global variable. but i don't have any idea? is anyone can help