cannot use geometry manager pack inside . which already has slaves managed by grid, although master windows are different

Question

I want to use grid to position frames in root, and use pack to position button in first frame. The master window is different, so why do I get this error?

root = Tk()

frame1 = LabelFrame(root, text="Frame1").grid(row=0, column=0)
frame2 = LabelFrame(root, text="Frame2").grid(row=0, column=1)


def open_file():
    pass

btn_import_image = Button(frame1, text="Import", command=open_file)
btn_import_image.pack()


root.mainloop()

Error:

_tkinter.TclError: cannot use geometry manager pack inside . which already has slaves managed by grid

Please examine the value of `frame1`. It's not what you think it is. This question has been asked many times on this site. — Bryan Oakley, Nov 12 '21 at 22:18
@BryanOakley I do not agree. This "many times" relates to mixing master windows, which I am not doing. — I.P., Nov 12 '21 at 22:25
Yes, you are. Did you examine `frame1` to see what it is? It is `None`. Using it as a parent has the exact same effect as setting the parent to `root`. — Bryan Oakley, Nov 12 '21 at 22:33
Oh........ Indeed.. Sorry and thank you. I thought about different kind of mistake. — I.P., Nov 12 '21 at 22:36

score 0 · Accepted Answer · answered Nov 12 '21 at 22:40

As @Bryan Oakley pointed out in the comment, using grid() returns None. So to fix it I had to separate instructions:

    frame1 = LabelFrame(root, text="Frame1")
    frame2 = LabelFrame(root, text="Frame2")

    frame1.grid(row=0, column=0)
    frame2.grid(row=0, column=1)

cannot use geometry manager pack inside . which already has slaves managed by grid, although master windows are different

1 Answers1