I’ve been trying to make a program, with 3 layouts depending on the window’s width (using Tkinter).

The issue is in the medium layout. Whenever I place my mouse onto the left canvas and use the MouseWheel, the right canvas scrolls, when the left canvas is supposed to. When my mouse is placed on the right canvas and I use the mouse wheel, the right canvas scrolls. I can’t find any solution to this.

import tkinter as tk
from tkinter import ttk
import random as rand

class App(tk.Tk):
    def init(self, Geometry, Icon, MinimumSizesDictionary):
        super().init() 

        self.title("Practise")
        self.geometry(f"{Geometry[0]}x{Geometry[1]}")
        self.minsize(Geometry[0], Geometry[1])
        self.iconbitmap(Icon)
    
        # variables
    
        self.MinimumSizesDictionary = MinimumSizesDictionary
    
        # widgets
    
        self.LayoutNSizeChecker = LayoutNSizeChecker(self, self.MinimumSizesDictionary)
    
        # run
        self.mainloop()

class LayoutNSizeChecker(ttk.Frame):
def init(self, Parent, MinimumSizesDictionary):
super ().init(Parent)

    self.pack(expand = True, fill = "both")
    self.MinimumSizesDictionary = MinimumSizesDictionary
    self.MinimumSize = self.CurrentMinimumSize = None
    self.Layout = None

    # binding an event to the main frame
    self.bind("<Configure>", lambda event : self.Update())

    # binding an event to the window
    Parent.bind("<Configure>", lambda event : self.CheckScreenSize(event, Parent))

def CheckScreenSize(self, event, Window):
    if event.widget == Window:

        for Key, Value in self.MinimumSizesDictionary.items():
            self.Delta = event.width - Key

            if self.Delta >= 0: self.MinimumSize = Key

        if self.CurrentMinimumSize != self.MinimumSize:
            self.CurrentMinimumSize = self.MinimumSize

            if self.CurrentMinimumSize == 300:
                for Widget in self.winfo_children():
                    Widget.destroy()
                    self.Destroyed = True

                print("small layout")
                self.Layout = "Small"

                # variables

                self.NumberOfButtons = 20
                self.SpaceEachRowTakes = 100
                self.TotalHeight = self.NumberOfButtons * self.SpaceEachRowTakes

                # canvas
                self.Canvas = tk.Canvas(self, scrollregion = (0, 0, self.winfo_width(), self.TotalHeight))
                self.Canvas.pack(expand = True, fill = "both")

                # canvas frame
                self.CanvasFrame = ttk.Frame(self)

                # scroll bar
                self.ScrollBar = ttk.Scrollbar(self, orient = "vertical", command = self.Canvas.yview)
                self.ScrollBar.place(relx = 1, rely = 0, relheight = 1, anchor = "ne")
                self.Canvas.config(yscrollcommand = self.ScrollBar.set)

                # scroll using the mousewheel
                self.Canvas.bind_all("<MouseWheel>", lambda event : self.Scroll(event))

                for i in range(1, 21):
                    self.FramePortion = ttk.Frame(self.CanvasFrame)

                    # variables

                    self.TextData = ["hello!", "goodbye!", "cya", "innit", "lol", "xd", "alr", "bro", "dude", "wsg"]

                    # making the grid

                    self.FramePortion.rowconfigure(0, weight = 1, uniform = "z")
                    self.FramePortion.columnconfigure((0, 1, 2), weight = 1, uniform = "z")

                    # the widgets
                                
                    self.Button1 = ttk.Button(self.FramePortion, text = i)
                    self.Button2 = ttk.Button(self.FramePortion, text = rand.choice(self.TextData))
                    self.Button3 = ttk.Button(self.FramePortion, text = rand.choice(self.TextData))

                    # placing the widgets onto the grid we created earlier

                    self.Button1.grid(row = 0, column = 0, sticky = "nesw", padx = 5, pady = 5)
                    self.Button2.grid(row = 0, column = 1, sticky = "nesw", padx = 5, pady = 5)
                    self.Button3.grid(row = 0, column = 2, sticky = "nesw", padx = 5, pady = 5)
                    self.FramePortion.pack(expand = True, fill = "both")
                    self.Destroyed = False
                    
            elif self.CurrentMinimumSize == 600:
                print("medium layout")
                self.Layout = "Medium"

                for Widget in self.winfo_children():
                    Widget.destroy()
                    self.Destroyed = True

                # grid for main frame

                self.rowconfigure(0, weight = 1, uniform = "z")
                self.columnconfigure((0, 2), weight = 6, uniform = "z")
                self.columnconfigure((1, 3), weight = 1, uniform = "z")

                # left side layout
                self.LeftFrame = ttk.Frame(self)
                self.LeftFrame.grid(row = 0, column = 0, sticky = "nesw")
                self.LeftCanvas = tk.Canvas(self.LeftFrame, scrollregion = (0, 0, self.LeftFrame.winfo_width(), self.TotalHeight / 2))
                self.LeftCanvas.pack(side = "left", pady = 10, expand = True, fill = "both")

                self.LeftCanvasFrame = ttk.Frame(self.LeftCanvas)

                # scroll bar
                self.LeftScrollBar = ttk.Scrollbar(self, orient = "vertical", command = self.LeftCanvas.yview)
                self.LeftScrollBar.grid(row = 0, column = 1, sticky = "ns")
                self.LeftCanvas.config(yscrollcommand = self.LeftScrollBar.set)

                # scroll using the mouse wheel
                self.LeftCanvas.bind_all("<MouseWheel>", lambda event : self.LeftScroll(event))

                for i in range(1, 11):
                    self.LeftFramePortion = ttk.Frame(self.LeftCanvasFrame)
                    self.Button4 = ttk.Button(self.LeftFramePortion, text = i)
                    self.Button5 = ttk.Button(self.LeftFramePortion, text = rand.choice(self.TextData))
                    self.Button6 = ttk.Button(self.LeftFramePortion, text = rand.choice(self.TextData))
                    self.Button4.pack(expand = True, fill = "both", padx = 2.5, pady = 2.5)
                    self.Button5.pack(expand = True, fill = "both", padx = 2.5, pady = 2.5)
                    self.Button6.pack(expand = True, fill = "both", padx = 2.5, pady = 2.5)
                    self.LeftFramePortion.pack(expand = True, fill = "both")

                # right side layout
                self.RightFrame = ttk.Frame(self)
                self.RightFrame.grid(row = 0, column = 2, sticky = "nesw")
                self.RightCanvas = tk.Canvas(self.RightFrame, scrollregion=(0, 0, self.RightFrame.winfo_width(), self.TotalHeight / 2))
                self.RightCanvas.pack(side = "left", pady = 10, expand = True, fill = "both")

                self.RightCanvasFrame = ttk.Frame(self.RightCanvas)

                # scroll bar
                self.RightScrollBar = ttk.Scrollbar(self, orient = "vertical", command = self.RightCanvas.yview)
                self.RightScrollBar.grid(row = 0, column = 3, sticky = "ns")
                self.RightCanvas.config(yscrollcommand = self.RightScrollBar.set)

                # scroll using the mouse wheel
                self.RightCanvas.bind_all("<MouseWheel>", lambda event : self.RightScroll(event))
                for i in range(11, 21):
                    self.RightFramePortion = ttk.Frame(self.RightCanvasFrame)
                    self.Button7 = ttk.Button(self.RightFramePortion, text = i)
                    self.Button8 = ttk.Button(self.RightFramePortion, text = rand.choice(self.TextData))
                    self.Button9 = ttk.Button(self.RightFramePortion, text = rand.choice(self.TextData))
                    self.Button7.pack(expand = True, fill = "both", padx = 2.5, pady = 2.5)
                    self.Button8.pack(expand = True, fill = "both", padx = 2.5, pady = 2.5)
                    self.Button9.pack(expand = True, fill = "both", padx = 2.5, pady = 2.5)
                    self.RightFramePortion.pack(expand = True, fill = "both")

                self.Destroyed = False

            elif self.CurrentMinimumSize == 1000:
                print("large layout")
                self.Layout = "Large"

                for Widget in self.winfo_children():
                    Widget.destroy()
                    self.Destroyed = True

def Update(self):
    if not self.Destroyed and self.Layout == "Small":
        self.Canvas.create_window(
            (0, 0),
            anchor = "nw",
            window = self.CanvasFrame,
            width = self.winfo_width(),
            height = self.TotalHeight
        )

    elif not self.Destroyed and self.Layout == "Medium":
        self.LeftCanvas.create_window(
            (0, 0),
            anchor = "nw",
            window = self.LeftCanvasFrame,
            width = self.LeftFrame.winfo_width(),
            height = self.TotalHeight / 2
        )

        self.RightCanvas.create_window(
            (0, 0),
            anchor = "nw",
            window = self.RightCanvasFrame,
            width = self.RightFrame.winfo_width(),
            height = self.TotalHeight / 2
        )

def Scroll(self, event):
    if not self.Destroyed and self.Layout == "Small":
        self.Canvas.yview_scroll(-int(event.delta / 60), "units")

def LeftScroll(self, event): # left scroll bar function for medium layout
    self.LeftCanvas.yview_scroll(-int(event.delta / 60), "units")

def RightScroll(self, event): # right scroll bar function for medium layout
    self.RightCanvas.yview_scroll(-int(event.delta / 60), "units")

App = App([300, 300], “icon.ico”, {300 : “Small”, 600 : “Medium”, 1000 : “Large”})

as always in the medium layout, whenever i use the mouse wheel, it scrolls the right canvas no matter what.