Traceback Errors After Destroying a Tkinter Image Widget (Python)

Question

I have a program that flashes red and blue on your screen very fast and it has a stop button. When the stop button is pressed the flashing stops but I also get a wall of errors which are all the same, they go so fast I can barley read them. Here is the error:

 Traceback (most recent call last):
      File "C:\Users\Mihkel\AppData\Local\Programs\Python\Python37-32\lib\tkinter\__init__.py", line 1702, in __call__
        return self.func(*args)
      File "C:\Users\Mihkel\AppData\Local\Programs\Python\Python37-32\lib\tkinter\__init__.py", line 746, in callit
        func(*args)
      File "C:\Users\Mihkel\Desktop\epiloop\Assets\example.py", line 27, in re
        label2.configure(image=redi)
      File "C:\Users\Mihkel\AppData\Local\Programs\Python\Python37-32\lib\tkinter\__init__.py", line 1482, in configure
        return self._configure('configure', cnf, kw)
      File "C:\Users\Mihkel\AppData\Local\Programs\Python\Python37-32\lib\tkinter\__init__.py", line 1473, in _configure
        self.tk.call(_flatten((self._w, cmd)) + self._options(cnf))
    _tkinter.TclError: invalid command name ".!label"
    Exception in Tkinter callback
    Traceback (most recent call last):
      File "C:\Users\Mihkel\AppData\Local\Programs\Python\Python37-32\lib\tkinter\__init__.py", line 1702, in __call__
        return self.func(*args)
      File "C:\Users\Mihkel\AppData\Local\Programs\Python\Python37-32\lib\tkinter\__init__.py", line 746, in callit
        func(*args)
      File "C:\Users\Mihkel\Desktop\epiloop\Assets\example.py", line 31, in blu
        label2.configure(image=bluei)
      File "C:\Users\Mihkel\AppData\Local\Programs\Python\Python37-32\lib\tkinter\__init__.py", line 1482, in configure
        return self._configure('configure', cnf, kw)
      File "C:\Users\Mihkel\AppData\Local\Programs\Python\Python37-32\lib\tkinter\__init__.py", line 1473, in _configure
        self.tk.call(_flatten((self._w, cmd)) + self._options(cnf))
    _tkinter.TclError: invalid command name ".!label"
    Exception in Tkinter callback
    Traceback (most recent call last):
      File "C:\Users\Mihkel\AppData\Local\Programs\Python\Python37-32\lib\tkinter\__init__.py", line 1702, in __call__
        return self.func(*args)
      File "C:\Users\Mihkel\AppData\Local\Programs\Python\Python37-32\lib\tkinter\__init__.py", line 746, in callit
        func(*args)
      File "C:\Users\Mihkel\Desktop\epiloop\Assets\example.py", line 31, in blu
        label2.configure(image=bluei)
      File "C:\Users\Mihkel\AppData\Local\Programs\Python\Python37-32\lib\tkinter\__init__.py", line 1482, in configure
        return self._configure('configure', cnf, kw)
      File "C:\Users\Mihkel\AppData\Local\Programs\Python\Python37-32\lib\tkinter\__init__.py", line 1473, in _configure
        self.tk.call(_flatten((self._w, cmd)) + self._options(cnf))
    _tkinter.TclError: invalid command name ".!label"

This is the code:

from tkinter import*

root = Tk()
root.geometry("500x500")
root.title("test")

time_interval = 260

#define images
redi = PhotoImage(file="red.gif")
bluei = PhotoImage(file="blue.gif")

def createimg2():#create the  image that will later be reconfigured to make it flash
    global label2
    label2 = Label(root, image=redi)
    label2.image1 = redi
    label2.image2 = bluei
    label2.pack()
    label2.place(x=0, y=0)

createimg2()


#the 4 following methods are what make the image flash
def re():
    root.after(time_interval, blu)
    label2.configure(image=redi)

def blu():
    root.after(time_interval, re)
    label2.configure(image=bluei)

def rbgo():
    root.after(time_interval, re)

def rb():
    re()
    blu()
    rbgo()

rb()

def kill(): #remove the flashing image
    label2.destroy()

btn = Button(root, text="stop", height=2, width=3, command=kill)
btn.pack(pady=100)


root.mainloop()

I believe that the problem is the fact that label1is a global variable. Is there a way I can not make it a global variable and have it still work? Note: I need the creation of the label to be in a method because this is actually a snippet of a much larger project.

Answer 1

Destroying the label doesn't stop the functions that try to reconfigure that label. It just makes them fail. The kill function should do something that causes the color-changing functions to stop. For example:

flag = True

def re():
    if flag:
        root.after(time_interval, blu)
        label2.configure(image=redi)

def blu():
    if flag:
        root.after(time_interval, re)
        label2.configure(image=bluei)

def kill(): #remove the flashing image
    global flag
    flag = False
    label2.destroy()