Tkinter: AttributeError: NoneType object has no attribute get

I have seen a couple of other posts on similar error message but couldn’t find a solution which would fix it in my case.

I dabbled a bit with TkInter and created a very simple UI. The code follows-

from string import *
from Tkinter import *
import tkMessageBox

root=Tk()
vid = IntVar()

def grabText(event):
    if entryBox.get().strip()=="":
        tkMessageBox.showerror("Error", "Please enter text")
    else:
        print entryBox.get().strip()    

root.title("My Sample")
root.maxsize(width=550, height=200)
root.minsize(width=550, height=200)
root.resizable(width=NO, height=NO)    

label=Label(root, text = "Enter text:").grid(row=2,column=0,sticky=W)
entryBox=Entry(root,width=60).grid(row=2, column=1,sticky=W)
grabBtn=Button(root, text="Grab")
grabBtn.grid(row=8, column=1)
grabBtn.bind('<Button-1>', grabText)

root.mainloop()

I get the UI up and running. When I click on the Grab button, I get the following error on the console:

C:\Python25>python.exe myFiles\testBed.py
Exception in Tkinter callback
Traceback (most recent call last):
  File "C:\Python25\lib\lib-tk\Tkinter.py", line 1403, in __call__
    return self.func(*args)
  File "myFiles\testBed.py", line 10, in grabText
    if entryBox.get().strip()=="":
AttributeError: 'NoneType' object has no attribute 'get'

The error traces back to Tkinter.py.

I’m sure some one might have dealt with this before. Any help is appreciated.

Tkinter: AttributeError: NoneType object has no attribute get