Question

I am trying to write a program that has twenty five buttons, when one is pressed, it will read from a text file, store it in a variable, then make the text of the label at the bottom of the page change to the text of the text file. Here is my code so far:

from Tkinter import*
box1 = 'C:/Users/Geekman2/Documents/Tests/box1.txt'
var = StringVar()
var.set("man")
def openfile(filename):
    filetxt = (open(filename,"r").read())
   #filetxt.set(iletxt)
    print filetxt
    return filetxt

def Box1():
    openfile(box1)


openfile(box1)
donut = Tk()
donut.geometry('450x450')

cupcake = Button(donut,text = "Box #1", command= Box1 )
cupcake.pack()

Whatsin = Label(donut,textvariable = var)
Whatsin.pack(side =BOTTOM)

donut.mainloop()

These two lines are giving me trouble, whenever I uncomment them and try to run the program I get the error “AttributeError: ‘NoneType’ object has no attribute ‘tk'”

var = Stringvar()
var.set("man")

Can anyone tell me what might be the cause of this? I know what the error means, but as far as I can tell it doesn’t apply in this situation

Answer 1

You need to instantiate an instance of Tk before you can use StringVar. Move donut = Tk() before your lines and it should work.