So, I followed an online video, and tried to replicate the UI, while applying my own changes to fit my needs, but I ended up with a UI that keeps enlarging every time I change the theme.

I tried commenting some parts of the code, to see where the problem lies, but to no avail, I’m pretty new to Tkinter, but I can handle my way after seeing a couple of examples, but this error, I couldn’t understand.

This is what it looks like:
https://youtu.be/3K3HWjYSB5s

And here’s a working code snippet:

import tkinter as tk

from tkinter import ttk

def toggle_mode():

if mode_switch.instate(["selected"]):

style.theme_use("forest-light")

else:

style.theme_use("forest-dark")

def select(event=None):

treeview.selection_toggle(treeview.focus())

print(treeview.selection())

root = tk.Tk()

root.title('Generator')

#root.geometry("1280x720")

style = ttk.Style(root)

root.tk.call("source", "Theme/forest-dark.tcl")

root.tk.call("source", "Theme/forest-light.tcl")

style.theme_use("forest-dark")

frame = ttk.Frame(root)

frame.pack(fill=tk.BOTH) #Expand the frame to fill the root window

widgets_frame = ttk.LabelFrame(frame, text="Title 2")

widgets_frame.grid(row=1, column=0, padx=20, pady=10)

mode_switch = ttk.Checkbutton(widgets_frame, text="Mode", style="Switch", command=toggle_mode)

mode_switch.grid(row=0, column=0, padx=5, pady=10, sticky="nsew")

separator = ttk.Separator(widgets_frame)

separator.grid(row=0, column=1, padx=(20, 0), pady=5, sticky="ew")

button = ttk.Button(widgets_frame, text="Generate")#, command=todo)

button.grid(row=0, column=2, padx=5, pady=5, sticky="nsew")

treeFrame = ttk.LabelFrame(frame, text="Title 1")

treeFrame.grid(row=0, column=0, pady=10, sticky="nsew")

treeScroll = ttk.Scrollbar(treeFrame)

treeScroll.pack(side="right", fill="y")

cols = ("1", "2", "3", "4")

treeview = ttk.Treeview(treeFrame, show=("headings"), selectmode="none", yscrollcommand=treeScroll.set, columns=cols, height=13)

treeview.bind("<ButtonRelease-1>", select)

treeview.column("1", width=100)

treeview.column("2", width=150)

treeview.column("3", width=300)

treeview.column("4", width=100)

treeview.pack()

treeview.pack_propagate(False)

treeScroll.config(command=treeview.yview)

#load_data()

root.mainloop()