Calling Tkinter frame controller from function rather then button command

You don't seem to initialize controller in self. Put it there in __init__ of LoginPage, like so:

self.controller = controller

my program has a page(main page) that has 5 radio button in it and a button "ok",and I have 5 other Frame. I want my program to go to these frames after clicking the "ok" ( based on the chosen radio button).

when the "ok" is clicked it will call a lambda and get the value of chosen radiobutton and based on this valuefind the string (veg) which represent the name of the page.

here is the code:

import tkinter as tkfrom tkinter import ttkfrom win32print import StartPage

class KBSapp(tk.Tk): def init(self, *args, **kwargs): tk.Tk.init(self, *args, **kwargs) tk.Tk.iconbitmap(self,default="icon.ico") tk.Tk.wm_title(self, "Diseases and pests of vegetable crops") container = tk.Frame(self, width=200, height=200, bg='black') 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,carrot,celery, potato, wheat, bean):        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, width=0, height=20)    label.pack()    button2 = ttk.Button(self, command=lambda : okclick(v) ,text='OK', width=25)    button2.pack( )    v = tk.IntVar( )    self.option1 = ttk.Radiobutton(self,  text="Carrot", variable=v, value=1);self.option1.pack( )    self.option2 = ttk.Radiobutton(self,  text="Celery", variable=v, value=2);self.option2.pack( )    self.option3 = ttk.Radiobutton(self,  text="potato", variable=v, value=3);self.option3.pack( )    self.option4 = ttk.Radiobutton(self,  text="wheat", variable=v, value=4);self.option4.pack( )    self.option5 = ttk.Radiobutton(self,  text="bean", variable=v, value=5);self.option5.pack( )    v.set(1)  # initializing the choice

def okclick(v): global veg input1=v.get( ) if input1==1: veg="carrot" if input1==2: veg='celery' if input1==3: veg='potato' if input1==4: veg='wheat' if input1==5: veg='bean' print(veg)

class carrot(tk.Frame): def init(self, parent, controller): tk.Frame.init(self, parent) label = tk.Label(self, width=0, height=20) label.pack( ) button3 = ttk.Button(self, command=lambda : controller.show_frame(celery) , text='celery', width=25) button3.pack( )

class celery(tk.Frame): def init(self, parent, controller): tk.Frame.init(self, parent) label = tk.Label(self, width=0, height=20) label.pack( ) button4 = ttk.Button(self, command=lambda : controller.show_frame(potato) , text='potato', width=25) button4.pack( )

class potato(tk.Frame): def init(self, parent, controller): tk.Frame.init(self, parent) label = tk.Label(self, width=0, height=20) label.pack( ) button4 = ttk.Button(self, command=lambda : controller.show_frame(wheat) , text='wheat', width=25) button4.pack( )

class wheat(tk.Frame): def init(self, parent, controller): tk.Frame.init(self, parent) label = tk.Label(self, width=0, height=20) label.pack( ) button4 = ttk.Button(self, command=lambda : controller.show_frame(bean) , text='bean', width=25) button4.pack( )

class bean(tk.Frame): def init(self, parent, controller): tk.Frame.init(self, parent) label = tk.Label(self, width=0, height=20) label.pack( ) button4 = ttk.Button(self, command=lambda : controller.show_frame(StartPage) , text='StartPage', width=25) button4.pack( )

app = KBSapp( )app.mainloop( )