How to change page through my menu bar methods in

Basically what I'm trying to figure out is, how do I make my menu bar "buttons" change the page?

I've already made the dropdown menu, and the classes with each page. The thing is it works if I create a separate button to change the page, but not when i'm trying to do it through the menu bar?

every tutorial I find is through the buttons, and only the buttons..

I am using python 3.6, with tkinter.

import tkinter as tk


class MyApp(tk.Tk):

    def __init__(self, *args, **kwargs, ):
        tk.Tk.__init__(self, *args, **kwargs)
        container = tk.Frame(self)

        container.pack(side="top", fill="both", expand=True)

        container.grid_rowconfigure(0, weight=1)
        container.grid_columnconfigure(0, weight=1)

        self.frames = {}

        menu = tk.Menu(container)

        betting = tk.Menu(menu, tearoff=0)
        menu.add_cascade(menu=betting, label="Pages")
        betting.add_command(label="PageOne",
                            command=lambda: controller.show_frame(PageOne))
        betting.add_command(label="PageTwo",
                            command=lambda: controller.show_frame(PageTwo))

        tk.Tk.config(self, menu=menu)

        for F in (Startpage, PageOne, PageTwo):
            frame = F(container, self)
            self.frames[F] = frame
            frame.grid(row=0, column=0, sticky="nsew")

        self.show_frame(Startpage)

    def show_frame(self, cont):

        frame = self.frames[cont]
        frame.tkraise()


class Startpage(tk.Frame):

    def __init__(self, parent, controller):
        tk.Frame.__init__(self, parent)
        label = tk.Label(self, text="Home")
        label.pack(pady=10, padx=10)

        button1 = tk.Button(self, text="page 1",
                        command=lambda: controller.show_frame(PageOne))
        button1.pack()
        button2 = tk.Button(self, text="Page Two",
                        command=lambda: controller.show_frame(PageTwo))
        button2.pack()


#   *****   PAGES   *****

class PageOne(tk.Frame):

    def __init__(self, parent, controller):
        tk.Frame.__init__(self, parent)
        label = tk.Label(self, text="Back to Home")
        label.pack(pady=10, padx=10)

        button1 = tk.Button(self, text="Back to Home",
                        command=lambda: controller.show_frame(Startpage))
        button1.pack()
        button2 = tk.Button(self, text="Page Two",
                        command=lambda: controller.show_frame(PageTwo))
        button2.pack()


class PageTwo(tk.Frame):

    def __init__(self, parent, controller):
        tk.Frame.__init__(self, parent)
        label = tk.Label(self, text="Page Two")
        label.pack(pady=10, padx=10)

        button1 = tk.Button(self, text="Back to Home",
                        command=lambda: controller.show_frame(Startpage))
        button1.pack()
        button2 = tk.Button(self, text="Page One",
                        command=lambda: controller.show_frame(PageOne))
        button2.pack()


app = MyApp()
app.geometry("1200x600")
app.mainloop()

Now I know, I haven't parsed the "controller & parent", right now, but I've tried and tried, and nothing works for me...

The controller is MyApp. Within the definition of MyApp that makes controller be self. Thus, you need to call self.show_frame rather than controller.show_frame.

betting.add_command(label="PageOne",
                    command=lambda: self.show_frame(PageOne))
betting.add_command(label="PageTwo",
                    command=lambda: self.show_frame(PageTwo))