Python Entry Widget data auto update and save in a text file

Question

I have a text file which contains four words line by line. suppose for example:

cat
mat
rat
hat

I want to show these words in an Entry widget. Like "cat" in first Entry widget, "mat" in second Entry widget and so on so. Now, if I update the contents of any Entry widget then it should also auto update in the text file. I wrote some codes to display Entry widgets but after that am not getting how to achieve this?

from tkinter import *
top = Tk()

with open('C:/Users/jaykr/Desktop/data.txt') as file:
    data = file.read().split("\n")

for i in range(len(data)):
    Entry(top).grid(row=i, column=0)

top.mainloop()

Answer 1

You can take advantage of tkinter's StringVar variable class and its trace() method. Here is an MCVE:

import tkinter as tk

root = tk.Tk()

entry_var = tk.StringVar()
entry = tk.Entry(root, width=10, textvariable=entry_var)
entry.pack()

def autoupdate(*args):
    with open('test.txt', 'w') as f:
        f.write(entry_var.get())

entry_var.trace('w', autoupdate)

root.mainloop()