import tkinter as tk
from tkinter import ttk

LARGEFONT =("Verdana", 35)

class tkinterApp(tk.Tk):
    def __init__(self, *args, **kwargs):
        # Relative import attempt
        from extra_pages.extra import Page2

        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 = {}

        for F in (StartPage, Page1, Page2):
            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):
        # Relative import attempt
        from extra_pages.extra import Page2

        tk.Frame.__init__(self, parent)
        label = ttk.Label(self, text ="Startpage", font = LARGEFONT)
        label.grid(row = 0, column = 4, padx = 10, pady = 10)

        button1 = ttk.Button(self, text ="Page 1",
        command = lambda : controller.show_frame(Page1))
        button1.grid(row = 1, column = 1, padx = 10, pady = 10)

        button2 = ttk.Button(self, text ="Page 2",
        command = lambda : controller.show_frame(Page2))
        button2.grid(row = 2, column = 1, padx = 10, pady = 10)


class Page1(tk.Frame):
    def __init__(self, parent, controller):
        # Relative import attempt
        from extra_pages.extra import Page2

        tk.Frame.__init__(self, parent)
        label = ttk.Label(self, text ="Page 1", font = LARGEFONT)
        label.grid(row = 0, column = 4, padx = 10, pady = 10)

        button1 = ttk.Button(self, text ="StartPage",
                             command = lambda : controller.show_frame(StartPage))
        button1.grid(row = 1, column = 1, padx = 10, pady = 10)

        button2 = ttk.Button(self, text ="Page 2",
                             command = lambda : controller.show_frame(Page2))
        button2.grid(row = 2, column = 1, padx = 10, pady = 10)


app = tkinterApp()
app.mainloop()