The demo for tcltk package in R

tcltk_demo.R

require('tcltk')

calcinp =''
mkput = function(sym){
  function(...){
    calcinp <<- paste(calcinp,sym,sep='')
    tkconfigure(display,text=calcinp)
  }
}
clearit = function(...){
  tkconfigure(display,text='')
  calcinp <<- ''
}
docalc = function(...){
  result = try(eval(parse(text=calcinp)))
  if(class(result) == 'try-error')calcinp <<- 'Error' else calcinp <<- result
  tkconfigure(display,text=calcinp)
  calcinp <<- ''
}
base = tktoplevel()
tkwm.title(base,'Calculator')
display = tklabel(base,justify='right')
tkpack(display,side='top')
row1 = tkframe(base)
tkpack(tkbutton(row1,text='7',command=mkput('7'),width=3),side='left')
tkpack(tkbutton(row1,text='8',command=mkput('8'),width=3),side='left')
tkpack(tkbutton(row1,text='9',command=mkput('9'),width=3),side='left')
tkpack(tkbutton(row1,text='+',command=mkput('+'),width=3),side='left')
tkpack(row1,side='top')
row2 = tkframe(base)
tkpack(tkbutton(row2,text='4',command=mkput('4'),width=3),side='left')
tkpack(tkbutton(row2,text='5',command=mkput('5'),width=3),side='left')
tkpack(tkbutton(row2,text='6',command=mkput('6'),width=3),side='left')
tkpack(tkbutton(row2,text='-',command=mkput('-'),width=3),side='left')
tkpack(row2,side='top')
row3 = tkframe(base)
tkpack(tkbutton(row3,text='1',command=mkput('1'),width=3),side='left')
tkpack(tkbutton(row3,text='2',command=mkput('2'),width=3),side='left')
tkpack(tkbutton(row3,text='3',command=mkput('3'),width=3),side='left')
tkpack(tkbutton(row3,text='*',command=mkput('*'),width=3),side='left')
tkpack(row3,side='top')
row4 = tkframe(base)
tkpack(tkbutton(row4,text='0',command=mkput('0'),width=3),side='left')
tkpack(tkbutton(row4,text='(',command=mkput('('),width=3),side='left')
tkpack(tkbutton(row4,text=')',command=mkput(')'),width=3),side='left')
tkpack(tkbutton(row4,text='/',command=mkput('/'),width=3),side='left')
tkpack(row4,side='top')
row5 = tkframe(base)
tkpack(tkbutton(row5,text='.',command=mkput('.'),width=3),side='left')
tkpack(tkbutton(row5,text='^',command=mkput('^'),width=3),side='left')
tkpack(tkbutton(row5,text='C',command=clearit,width=3),side='left')
tkpack(tkbutton(row5,text='=',command=docalc,width=3),side='left')
tkpack(row5,side='top')
mkfun = function(fun){
  function(...){
    calcinp <<- paste(fun,'(',calcinp,')',sep='')
    tkconfigure(display,text=calcinp)
  }
}
row6 = tkframe(base)
tkpack(tkbutton(row6,text='sqrt',command=mkfun('sqrt'),width=3),side='left')
tkpack(tkbutton(row6,text='exp',command=mkfun('exp'),width=3),side='left')
tkpack(tkbutton(row6,text='qnorm',command=mkfun('qnorm'),width=3),side='left')
tkpack(row6,side='top')