# NOT RUN {
## These cannot be run by examples() but should be OK when pasted
## into an interactive R session with the tcltk package loaded
tt <- tktoplevel()
label.widget <- tklabel(tt, text = "Hello, World!")
button.widget <- tkbutton(tt, text = "Push",
                          command = function()cat("OW!\n"))
tkpack(label.widget, button.widget) # geometry manager
                                    # see Tk-commands
## Push the button and then...
tkdestroy(tt)
## test for themed widgets
if(as.character(tcl("info", "tclversion")) >= "8.5") {
  # make use of themed widgets
  # list themes
  as.character(tcl("ttk::style", "theme", "names"))
  # select a theme -- here pre-XP windows
  tcl("ttk::style", "theme", "use", "winnative")
} else {
  # use Tk 8.0 widgets
}
# }
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