Fix No Module Named Tkinter Error in Python

Hi there! So, I’m working on building a basic Tkinter program that lets the user enter a password, and if it’s correct, it takes them to another page (or does something). The idea is that if the user enters a wrong password, a small error message saying “Incorrect Password” should appear and then disappear after 2 seconds. Sounds simple enough, right?

Well, it works perfectly the first time I enter a wrong password, the error message shows up, and after 2 seconds, it disappears just as expected. But then, if I enter the wrong password again, nothing happens. No error message, just a flood of errors that I can’t figure out.

I’ve included the code below, if any of you smart folks can spot what I’m doing wrong;

Error Code:

codefrom tkinter import *
import threading

master_pwd = "yoyodojo"
pwd_correct = False

root = Tk()
root.geometry("1080x720")

password_frame = Frame(root, bg="#D3D3D3", highlightbackground="black", highlightthickness=3)
password_frame.place(relwidth=0.4, relheight=0.25, relx=0.3, rely=0.325)

incorrect_label = Label(password_frame, text="Incorrect Password", font="Helvetica, 10", foreground="Red",
                        background="#D3D3D3")

def hide_incorrect_label():
    incorrect_label.destroy()

def check_pwd(inputted_pwd):
    if inputted_pwd == master_pwd:
        global pwd_correct
        pwd_correct = True
        root.destroy()
    else:
        pwd_correct = False
        password_input.delete(0, END)
        incorrect_label.place(relx=0.33, rely=0.82)
        x = threading.Timer(2.0, hide_incorrect_label)
        x.start()

password_input = Entry(password_frame, relief=RIDGE, bg="#4f4f4f", fg="white", font="Helvetica, 14",
                       justify="center")
password_input.bind("<Return>", (lambda event: check_pwd(password_input.get())))
password_input.place(relwidth=0.8, relheight=0.2, relx=0.1, rely=0.6)

pwd_label = Label(password_frame, text="Enter Master Password:", font="Helvetica, 24", background="#D3D3D3")
pwd_label.pack(pady=20)

root.mainloop()

Here is the error I am getting:

codeException in Tkinter callback

Traceback (most recent call last):

  File "C:\Users\benma\AppData\Local\Programs\Python\Python310\lib\tkinter\__init__.py", line 1921, in __call__
    return self.func(*args)

  File "C:\Users\benma\Documents\Coding\File Hider\Code\Gui.py", line 37, in <lambda>
    password_input.bind("<Return>", (lambda event: check_pwd(password_input.get())))

  File "C:\Users\benma\Documents\Coding\File Hider\Code\Gui.py", line 30, in check_pwd
    incorrect_label.place(relx=0.33, rely=0.82)

  File "C:\Users\benma\AppData\Local\Programs\Python\Python310\lib\tkinter\__init__.py", line 2477, in place_configure
    self.tk.call(_tkinter.TclError: bad window path name ".!frame.!label"

Here’s a correct and well-documented version of your code, along with an explanation of how it works:

Corrected Code:

codefrom tkinter import *
import threading

# Global variables
master_pwd = "yoyodojo"  # The correct password
pwd_correct = False  # Track whether the correct password was entered

# Create the main root window
root = Tk()
root.geometry("1080x720")  # Set the size of the window

# Create a frame to hold the password input widgets
password_frame = Frame(root, bg="#D3D3D3", highlightbackground="black", highlightthickness=3)
password_frame.place(relwidth=0.4, relheight=0.25, relx=0.3, rely=0.325)

# Label to display incorrect password message (initially hidden)
incorrect_label = Label(password_frame, text="Incorrect Password", font=("Helvetica", 10), 
                        foreground="Red", background="#D3D3D3")

def hide_incorrect_label():
    """
    Hide the 'Incorrect Password' label after 2 seconds.
    """
    incorrect_label.place_forget()  # Use place_forget() instead of destroy() to hide

def check_pwd(inputted_pwd):
    """
    Check if the inputted password matches the master password.
    If it matches, close the root window. If not, show the error label.
    """
    global pwd_correct
    if inputted_pwd == master_pwd:
        pwd_correct = True
        root.destroy()  # Close the window if the password is correct
    else:
        pwd_correct = False
        password_input.delete(0, END)  # Clear the input field
        incorrect_label.place(relx=0.33, rely=0.82)  # Show the incorrect password message
        threading.Timer(2.0, hide_incorrect_label).start()  # Hide the message after 2 seconds

# Create the password input field
password_input = Entry(password_frame, relief=RIDGE, bg="#4f4f4f", fg="white", font=("Helvetica", 14), 
                       justify="center", show="*")  # 'show="*"' masks the input
password_input.bind("<Return>", lambda event: check_pwd(password_input.get()))  # Bind Enter key to password check
password_input.place(relwidth=0.8, relheight=0.2, relx=0.1, rely=0.6)

# Label prompting the user to enter the password
pwd_label = Label(password_frame, text="Enter Master Password:", font=("Helvetica", 24), background="#D3D3D3")
pwd_label.pack(pady=20)

# Run the GUI event loop
root.mainloop()

Explanation:

1. Window Initialization:
   • We create a Tkinter window (root) and set its size to 1080×720 pixels using geometry().
2. Password Frame:
   • A Frame is used to group the password input field and labels. This makes the UI more structured.
3. Label for Incorrect Password:
   • We define a label (incorrect_label) to show an error message if the password is incorrect. Initially, this label is hidden.
4. Password Input and Binding:
   • The Entry widget is used for the password input. We add show="*" to mask the input (commonly used for passwords).
   • We bind the Enter key event (<Return>) to the function that checks the password, so users can press Enter to submit.
5. Password Checking Function (check_pwd):
   • If the input matches master_pwd, we set pwd_correct to True and close the window using root.destroy().
   • If the password is incorrect, the input field is cleared, and the error label is shown for 2 seconds using threading.Timer.
6. Timer for Error Message:
   • threading.Timer allows the error label to disappear after 2 seconds. Instead of destroying the label, we use place_forget() to hide it. This is more efficient than destroying and recreating it.
7. Event Loop (root.mainloop()):
   • This starts the Tkinter event loop, keeping the GUI active and responsive to user inputs.

Final Thoughts:

This code provides a simple and functional password verification GUI using Tkinter. Here are some key improvements and recommendations:

• Error Handling: Instead of destroying the label every time, we use place_forget() to hide it, which is more efficient.
• Input Masking: Adding show="*" to the password input field improves security by masking the entered text.
• Threading: Using threading.Timer ensures that the GUI remains responsive while the error message is temporarily displayed.
• Future Improvements:
  • You could add functionality to limit the number of attempts.
  • Implement more advanced security practices (like hashing passwords) if this were part of a real application.

This version ensures good user experience and code readability, while also being maintainable and easy to understand.