How to make a flashing text box in tkinter?

Question

So my computing class are making a xmas card in python, and for one of the bits there is going to be a text box with a message, but how do I make the background alternate from green and red ?

If someone would be able to help that would be amazing :)

from tkinter import *
root = Tk()
root.title("Xmas Message")

#command for the button
def test_com():
    #removing the button
    act_btn.grid_remove() 

#adding the textbox for the message
msg_box = Text(root, height = 1, width = 30)
msg_box.grid(row=0, column=0)

#adding the message
msg_box.insert(END, "Happy Xmas")

#changing the background to green
msg_box.config(background="green")


#changing the background to red
msg_box.config(background="red")

root.after(250, test_com)


#button for activating the command
act_btn = Button(root, text = "1", command = test_com)
act_btn.grid(row=0, column=0)






root.mainloop()

Solution

Create a change_color callback that alternates the text box's color, and uses after to call itself a second in the future.

Sample implementation:

from tkinter import *

def change_color():
    current_color = box.cget("background")
    next_color = "green" if current_color == "red" else "red"
    box.config(background=next_color)
    root.after(1000, change_color)

root = Tk()
box = Text(root, background="green")
box.pack()
change_color()
root.mainloop()