Invalid Command Name Error

[NamanChhabra21]

I am getting these errors while closing/reopening CustomTkinter windows:

invalid command name "1829407468544update"
    while executing
"1829407468544update"
    ("after" script)

invalid command name "1829407471168check_dpi_scaling"
    while executing
"1829407471168check_dpi_scaling"
    ("after" script)

This happens when I destroy a CTk() window and reopen it again later.

The program still exits with code 0 and works normally, but the terminal prints these errors.

Does anyone know about this??

You can run this code to get the same error

from customtkinter import *
set_appearance_mode("default")

def center_window(window, width, height):
    # Get screen width and height
    screen_width = window.winfo_screenwidth()
    screen_height = window.winfo_screenheight()

    # Calculate X and Y coordinates for the top-left corner
    x = (screen_width // 2) - (width // 2)
    y = (screen_height // 2) - (height // 2)

    window.geometry(f"{width}x{height}+{x}+{y}")

def delete(window):
    window.destroy()
    return

class RateUs:
    def __init__(self):

        root = CTk("black")

        root.overrideredirect(True)
        center_window(root, 300, 340)
        x_button = CTkButton(root, text="X", font=("george", 20), command=lambda: delete(root), width=40, height=40,
                             corner_radius=0, fg_color="red", hover_color="red3")
        x_button.pack(anchor="ne")

        rateus = CTkLabel(root,text="Rate Us",text_color="white",font=("impact",40))
        rateus.pack(pady=(0,0),padx=(0,0))

        star_frame = CTkFrame(root,width=300,height=100,fg_color="black")
        star_frame.pack(pady=(30,0))

        stars = {}

        rating_messages = ["Poor","Not Good","Good !","Fantastic !!!","Loved it !!!!!!"]
        def fill_color(index):

            # Fill first `i` stars
            for star in range(0,index+1):
                stars[star].configure(text_color="yellow")

            # Fill remaining stars
            for star in range(index+1, 5):
                stars[star].configure(text_color="white")

            # Change rating message
            star_message.configure(text = rating_messages[index])

            # Show submit button
            submit.pack_forget()
            submit.configure(command=lambda x = index+1:self.submit(x,root))
            submit.pack(pady=(20,0))
        star_message = CTkLabel(star_frame,text="",font=("default",20),text_color="white")
        star_message.grid(row=1,columnspan=5,pady=(8,0))
        for i in range(0,5):
            stars[i] = CTkButton(star_frame,text="★",command=lambda x=i:fill_color(x),width=30,height=70,font=("Segoe UI Emoji",30),fg_color="black",hover_color="gray10")
            stars[i].grid(row=0,column=i,padx=2)

        # message_text = "Rating helps us to Improve !"
        message_text = "Click on X button to get error"

        submit = CTkButton(root,text="Submit!",font=("default",20),fg_color="green",width=20,corner_radius=5,hover_color="green3")
        submit.pack_forget()

        message = CTkLabel(root,text=message_text,font=("default",20),text_color="white")
        message.pack()
        root.mainloop()

    @staticmethod
    def submit(rating,window):
        delete(window)

        # Saving rating in UserData.json | This updates data at `firebasedatabase`
        # DataHandling.update_rating(rating)
        return

# ERROR OCCURS HERE
RateUs()
RateUs()
RateUs()

[FedericoSpada]

Hi,
Those errors appear because there are some after() tasks that haven't been stopped when the app is closed.
after() is used by this library to run some infinite loops that check for appearance mode and scaling factor, so they are meant to be run constantly. It is also strange that you restart the application after it has been closed.

In any case, to avoid the problem, you can add this after root.mainloop():

for after_id in root.after_info():
    root.after_cancel(after_id)

I'll fix it in the next release of Custom2kinter, the new repository that continues the development of this library.