Tkinter - Command or callback function for Menu item
Set command function for Menu item in Tkinter
To call a command function when a menu item is clicked, pass the callback function name as value for the command parameter when you are adding the menu item to the menu.
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For example, consider that we are adding an item Item1 to the menu. We specify a function item_1_action as value for the command parameter.
my_menu.add_command(label="Item1", command=item_1_action)
When user clicks on the menu item Item1, the item_1_action() function is called.
In this tutorial, you will learn how to call a respective callback command function when user clicks on a menu item.
Example
In this example, we shall create a menu with two menu items. When user clicks on the first item Item1, we call item_1_action() callback command function. Similarly, when user clicks on the second item Item2, we call item_2_action() callback command function.
Program
import tkinter as tk
def item_1_action():
print('You clicked Item1.')
def item_2_action():
print('You clicked Item2.')
# Create the main window
window = tk.Tk()
window.title("PythonExamples.org")
window.geometry("300x200")
# Create the menu bar
menu_bar = tk.Menu(window)
# Create the menu
menu_1 = tk.Menu(menu_bar, tearoff=0)
# Add items for Menu1
menu_1.add_command(label="Item1", command=item_1_action)
menu_1.add_command(label="Item2", command=item_2_action)
# Add the menu to the menu bar
menu_bar.add_cascade(label="Menu1", menu=menu_1)
# Attach the menu bar to the main window
window.config(menu=menu_bar)
# Start the Tkinter event loop
window.mainloop()
Output
Run on MacOS.
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Click on Item1 or Item2.
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Summary
In this Python Tkinter tutorial, we learned how to specify a callback command function for a menu item, so that the function executes when user clicks on the menu item, with the help of examples.