R/aveytoolkit_getLoginDetails.R

In stefanavey/aveytoolkit: Toolkit of Helper Functions

##' getLoginDetails
##'
##' Uses tcltk to display a prompt for a loginID and password
##'
##' @return an invisible named vector of loginID and password
##' @author Markus Gesmann, Barry Rowlingson
##' @details This function displays a window for a user to enter a loginID
##'          and password without showing the password. It may be bad package
##'          etiquette that \code{tcltk} is required for this function but not
##'          imported in the NAMESPACE file. This is done because loading
##'          \code{tcltk} will not work without a display and I want to be
##'          able to use this package (even if not this function) without a
##'          display
##' @keywords aveytoolkit
##' @seealso \code{tcltk}
##' @references \url{http://www.r-bloggers.com/simple-user-interface-in-r-to-get-login-details/} \url{http://r.789695.n4.nabble.com/tkentry-that-exits-after-RETURN-tt854721.html#none}
##' @examples
##' credentials <- getLoginDetails()
##' ## Do what needs to be done with loginID and password
##' rm(credentials) # Delete credentials
getLoginDetails <- function(){
  ## Based on code by Barry Rowlingson
  ## http://r.789695.n4.nabble.com/tkentry-that-exits-after-RETURN-tt854721.html#none
  tt<-tktoplevel()
  tkwm.title(tt,"Get login details")
  Name <- tclVar("Login ID")
  Password <- tclVar("Password")
  entry.Name <-tkentry(tt,width="20",textvariable=Name)
  entry.Password <-tkentry(tt,width="20", show="*",textvariable=Password)
  tkgrid(tklabel(tt,text="Please enter your login details."))
  tkgrid(entry.Name)
  tkgrid(entry.Password)
  OnOK <- function() {
    tkdestroy(tt)
  }
  OK.but <-tkbutton(tt,text=" OK ",command=OnOK)
  tkbind(entry.Password, "<Return>",OnOK)
  tkgrid(OK.but)
  tkfocus(tt)
  tkwait.window(tt)
  invisible(c(loginID=tclvalue(Name), password=tclvalue(Password)))
}