Myujth

I'm having a problem with how to run some piece of code on some state of OptionMenu.

from tkinter import *

class Browser(Frame):
 def __init__(self, root):
 self.root = root
 super().__init__(self.root)
 self.createUtility()
 return

 def createUtility(self):
 self.main_frame = Frame(bg="")
 self.main_frame.grid(row=0, column=0)

 self.display_frame = Frame(width=50, height=50, bg="")
 self.display_frame.grid(row=1, column=0)

 options = ["Plants", "Wood", "Mushrooms", "Animals"]

 self.variable = StringVar()
 self.variable.set("Wood")
 self.change_menu = OptionMenu(self.main_frame, self.variable, *options, command=self.func)
 self.change_menu.grid(row=0, column=0)

 self.exit_button = Button(self.display_frame, text="Quit!", command=quit)
 self.exit_button.grid(row=1, column=1)

 if value == "Plants":
 #do some code
 elif value == "Wood":
 #do some code
 elif value == "Mushrooms":
 #do some code
 elif value == "Animals":
 #do some code 
 else:
 #do some code 
 return

 def func(self, value):
 return value
 #This value should be used for an if block in createUtility function

if __name__ == "__main__":
 b = Browser(Tk())
 mainloop()

I don't get errors, so that's good. I can click and select options in OptionMenu but nothing happens.

First I want to say that not getting an error does not by default mean "good". There could be many reason for not getting an error and still have problems.

Now moving on to the code itself. You have a few problems.

1. Your method func is not doing anything useful here. Returning the event back to the menu item will result in nothing as it is being ignored by the OptionMenu. So here you would get no error because it is ignored.




2. Your if/elif statement will only run once and should fail with the error: NameError: name 'value' is not defined. Due to value never being defined in the createUtility method.




3. Your use of return is not needed in any of these places and in fact does nothing useful.




4. b = Browser(Tk()) mainloop() Is not a good approach. You need to be more explicit on your tkinter instance.




5. Small grievance but worth mentioning. Instead of doing from tkinter import * you should do import tkinter as tk and use thetk. prefix where needed. This will help prevent accidental overtiring of imports form tkinter.

Change it to something like this:

if __name__ == "__main__":
 root = Tk()
 Browser(root)
 root.mainloop()

Code:

import tkinter as tk

class Browser(tk.Frame):
 def __init__(self, root):
 super().__init__(root)
 main_frame = tk.Frame(bg="")
 display_frame = tk.Frame(width=50, height=50, bg="")
 main_frame.grid(row=0, column=0)
 display_frame.grid(row=1, column=0)

 options = ["Plants", "Wood", "Mushrooms", "Animals"]

 self.variable = tk.StringVar()
 self.variable.set("Wood")
 self.change_menu = tk.OptionMenu(main_frame, self.variable, *options, command=self.check_value)
 self.exit_button = tk.Button(display_frame, text="Quit!", command=quit)
 self.change_menu.grid(row=0, column=0)
 self.exit_button.grid(row=1, column=1)

 def check_value(self, event):
 if event == "Plants":
 print(event)
 elif event == "Wood":
 print(event)
 elif event == "Mushrooms":
 print(event)
 elif event == "Animals":
 print(event)
 else:
 print("No match") 


if __name__ == "__main__":
 root = tk.Tk()
 Browser(root)
 root.mainloop()