模块独立工作，但导入时出现错误

Question

So I was working with tkinter.tix module in Python to make a Scrollable window. It works flawlessly when I run the module independently but when I import it, it raises an error. Even if I independently import the tkinter.tix module in the main program, it causes error with other module in the main program( Image module from PIL which works perfectly until I import the tkinter.tix module, after which it of course raises an error). Has anyone encountered this error before? Any help will be really appreciated. Thanks

Code:

Main Program:

from PIL import Image, ImageTk
import TCRMenuOptions, STUMenuOptions

assignment = tk.Button(   #This button calls the function to display assignments
        master=frame,
        text="Assignment",
        font=font.Font(size=20, family="Helvetica"),
        image = asimg,
        compound = "top",
        width=200,
        height = 210,
        activebackground="White",
        bg="#33FFC5",
        bd=2,
        fg="DarkSlateGray",
        command = lambda: STUMenuOptions.viewassign(cls)
    )

STUMenuOptions Module:

def viewassign(cls):
    root1 = Tk()
    root1.config(background="#303939")
    root1.state('zoomed')
    frame = Frame(root1, bg="#303939", width="1366", height="768").grid(row=0, column=0)
    swin = ScrolledWindow(frame, width="1366", height="768")
    swin.grid(row=0, column=0)
    root = swin.window
    root.config(background="#303939")
    cls_lbl = Label(root, text="Current Assignments", font=font.Font(size=50, weight="bold"),bg="#303939", fg="Cyan").grid(row = 0, column = 0)

# Plus some other non relevant code

So when the button is pressed in the main program, it calls the viewassign(cls) function from STUMenuOptions module which it does, but then a blank window appears (There should be atleast the label "Current Assignments"; atleast for the code I am posting here)and it raises the error which I have posted in previous edit but I am posting the full one:

Traceback (most recent call last):
  File "C:\Users\abc2\AppData\Local\Programs\Python\Python36\lib\tkinter\__init__.py", line 1699, in __call__
    return self.func(*args)
  File "C:/Users/abc2/Python/ComputerScienceProject/Main.py", line 324, in <lambda>
    command = lambda: STUMenuOptions.viewassign(cls)
  File "C:\Users\abc2\Python\ComputerScienceProject\STUMenuOptions.py", line 466, in viewassign
    swin = ScrolledWindow(frame, width="1366", height="768")
  File "C:\Users\abc2\AppData\Local\Programs\Python\Python36\lib\tkinter\tix.py", line 1348, in __init__
    TixWidget.__init__(self, master, 'tixScrolledWindow', ['options'], cnf, kw)
  File "C:\Users\abc2\AppData\Local\Programs\Python\Python36\lib\tkinter\tix.py", line 315, in __init__
    self.tk.call(widgetName, self._w, *extra)
_tkinter.TclError: invalid command name "tixScrolledWindow"

Answer 1

You did this:

frame = Frame(root1, bg="#303939", width="1366", height="768").grid(row=0, column=0)

In there you create a tk.Frame and immediately call its .grid method and store the result from the .grid (which is always None) in the variable frame . Then when you pass it in to ScrolledWindow(frame, ...) it confuses tkinter.

What you actually wanted to do is this:

frame = Frame(root1, bg="#303939", width="1366", height="768")
frame.grid(row=0, column=0)

This problem is very similar to this one. Always split creating the widget and packing/placing/gridding the widget on separate lines.