import tkinter as tk from UserPage import UserPage from ChatListPage import ChatListPage from ChatPage import ChatPage from AppLogic import AppLogic from CreatePage import CreatePage if __name__ == '__main__': AppLogic.container = tk.Frame(AppLogic.root) AppLogic.container.pack(side="top", fill="both", expand=True) # initialize all page user_page = UserPage(AppLogic.container) chat_list_page = ChatListPage(AppLogic.container) create_page = CreatePage(AppLogic.container) user_page.place(in_=AppLogic.container, x=0, y=0, relwidth=1, relheight=1) chat_list_page.place(in_=AppLogic.container, x=0, y=0, relwidth=1, relheight=1) create_page.place(in_=AppLogic.container, x=0, y=0, relwidth=1, relheight=1) # set path user_page.next_page = chat_list_page chat_list_page.create_page = create_page create_page.redirect_page = chat_list_page # set user_page as first page user_page.lift() AppLogic.root.mainloop() if __name__ == '__test__': root = tk.Tk() container = tk.Frame(root) container.pack(side="top", fill="both", expand=True)