How to Create Menus and Status Bars in Python Tkinter

import tkinter as tk
from tkinter import messagebox


def some_function():
    # This function is called when some menu items are clicked.
    messagebox.showinfo("Menu Demo", "some_function() was called.")


def exit_app():
    # This function closes the entire application.
    # root.quit() ends the tkinter event loop.
    root.quit()

# ---------------- Main Application Window ---------------- #
# Create the main window where everything lives.
root = tk.Tk()
root.title("Basic Menu Demo")  # Window title at the top
root.geometry("400x300")         # Width = 400 pixels, Height = 300 pixels

# ---------- Menu Bar (the strip at the top of the window) ---------- #
# Create a Menu object, which will hold all the dropdown menus.
menubar = tk.Menu(root)

# tkinter has a "tear off" feature for menus by default that
# isn't used in mainstream software, so we'll disable it.
# (The tear off feature doesn't work at all on macOS.)

file_menu = tk.Menu(menubar, tearoff=1)  # tearoff=0 removes the dashed line at the top
file_menu.add_command(label="New", command=some_function)   # "New" item
file_menu.add_command(label="Open", command=some_function) # "Open" item
file_menu.add_separator()                              # Adds a dividing line
file_menu.add_command(label="Exit", command=exit_app)  # "Exit" item

menubar.add_cascade(label="File", menu=file_menu)      # Attach File menu to menubar

# Attach the menubar to the window so it actually shows up.
root.config(menu=menubar)

# ---------------- Main Loop ---------------- #
# This line starts the tkinter event loop, which waits for the user
# to click buttons, menus, or close the window. Without this, the
# window would open and close instantly.
root.mainloop()

import tkinter as tk
from tkinter import messagebox

# ---------------- Functions that are called when menu items are clicked ---------------- #

def some_function():
    # This function is called when some menu items are clicked.
    messagebox.showinfo("Menu Demo", "some_function() was called.")


def exit_app():
    # This function closes the entire application.
    # root.quit() ends the tkinter event loop.
    root.quit()


def toggle_func():
    # This function shows or hides the status bar depending on
    # whether the checkbutton in the View menu is checked.
    messagebox.showinfo("Menu Demo", f"Menu item checked == {toggle_setting.get()}")


def change_theme():
    # This function runs when a radiobutton in the Theme menu is clicked.
    # Only one theme can be selected at a time.
    selected = theme_choice.get()
    messagebox.showinfo("Theme Selected", f"You chose: {selected}")


# ---------------- Main Application Window ---------------- #

# Create the main window where everything lives.
root = tk.Tk()
root.title("Checkbox and Radio Button Menu Demo")      # Window title at the top
root.geometry("400x300")             # Width = 400 pixels, Height = 300 pixels

# ---------------- Menu Bar (the strip at the top of the window) ---------------- #

# Create a Menu object, which will hold all the dropdown menus.
menubar = tk.Menu(root)

# --- File menu ---
file_menu = tk.Menu(menubar, tearoff=0)  # tearoff=0 removes the dashed line at the top
file_menu.add_command(label="New", command=some_function)   # "New" item
file_menu.add_command(label="Open", command=some_function) # "Open" item
file_menu.add_separator()                             # Adds a dividing line
file_menu.add_command(label="Exit", command=exit_app)  # "Exit" item
menubar.add_cascade(label="File", menu=file_menu)      # Attach File menu to menubar

# --- View menu with a checkbutton ---
view_menu = tk.Menu(menubar, tearoff=0)
# BooleanVar is a tkinter variable type that can only be True/False.
# It is linked to the checkbutton so we know if it is checked or not.
toggle_setting = tk.BooleanVar(value=True)
view_menu.add_checkbutton(
    label="Checkbox Menu Item",     # What the menu item says
    onvalue=True, offvalue=False,   # Values for checked/unchecked
    variable=toggle_setting,        # Link this menu item to the BooleanVar
    command=toggle_func        # Function to run when clicked
)
menubar.add_cascade(label="View", menu=view_menu)

# --- Theme menu with radiobuttons ---
theme_menu = tk.Menu(menubar, tearoff=0)
# StringVar is another tkinter variable type that stores text.
# It will store the name of the currently selected theme.
theme_choice = tk.StringVar(value="A")
theme_menu.add_radiobutton(label="Option A", variable=theme_choice,
                           value="A", command=change_theme)
theme_menu.add_radiobutton(label="Option B", variable=theme_choice,
                           value="B", command=change_theme)
theme_menu.add_radiobutton(label="Option C", variable=theme_choice,
                           value="C", command=change_theme)
menubar.add_cascade(label="Theme", menu=theme_menu)

# Attach the menubar to the window so it actually shows up.
root.config(menu=menubar)

# ---------------- Main Loop ---------------- #
# This line starts the tkinter event loop, which waits for the user
# to click buttons, menus, or close the window. Without this, the
# window would open and close instantly.
root.mainloop()

import tkinter as tk
from tkinter import messagebox

# ---------------- Main Application Window ---------------- #
# Create the main window where everything lives.
root = tk.Tk()
root.title("Submenu Demo")      # Window title at the top
root.geometry("400x300")             # Width = 400 pixels, Height = 300 pixels

# ---------------- Menu Bar (the strip at the top of the window) ---------------- #
# Create a Menu object, which will hold all the dropdown menus.
menubar = tk.Menu(root)
main_menu = tk.Menu(menubar, tearoff=0)

# --- Submenu 1 ---
submenu1 = tk.Menu(main_menu, tearoff=0)
submenu1.add_command(label="Option 1A", command=lambda: messagebox.showinfo("Action", f"You chose: 1A"))
submenu1.add_command(label="Option 1B", command=lambda: messagebox.showinfo("Action", f"You chose: 1B"))

# Add submenu1 to the main menu
main_menu.add_cascade(label="Submenu 1", menu=submenu1)

# --- Submenu 2 ---
submenu2 = tk.Menu(main_menu, tearoff=0)
submenu2.add_command(label="Option 2A", command=lambda: messagebox.showinfo("Action", f"You chose: 2A"))
submenu2.add_command(label="Option 2B", command=lambda: messagebox.showinfo("Action", f"You chose: 2B"))

# Add submenu2 to the main menu
main_menu.add_cascade(label="Submenu 2", menu=submenu2)

# Add the main menu to the menubar
menubar.add_cascade(label="Main", menu=main_menu)

# Attach the menubar to the root window
root.config(menu=menubar)

root.mainloop()

import tkinter as tk

# Counter starts at 0
counter = 0

def increment_counter():
    """Increase the counter value by 1 and update the status bar text."""
    global counter
    counter += 1
    statusbar.config(text=f"Counter: {counter}")

# ---------------- Main Application Window ---------------- #
# Create the main window.
root = tk.Tk()
root.title("Status Bar Demo")
root.geometry("300x150")

# --------- Status Bar (a label at the bottom of the window) -------- #
# Status bar at the bottom.
# relief can also be set to tk.FLAT, tk.RAISED, tk.GROOVE, or tk.RIDGE
# anchor=tk.E will make it right-aligned ("east").
# side=tk.TOP is possible but unconventional.
# side=tk.LEFT and side=tk.RIGHT is rather ugly.
statusbar = tk.Label(root, text=f"Counter: {counter}",
                     bd=1, relief=tk.SUNKEN, anchor=tk.W)
statusbar.pack(side=tk.BOTTOM, fill=tk.X)

# Button to call increment_counter() when clicked.
increment_button = tk.Button(root, text="Increment the Counter",
                             command=increment_counter)
increment_button.pack(pady=20)

# ---------------- Main Loop ---------------- #
# This line starts the tkinter event loop, which waits for the user
# to click buttons, menus, or close the window. Without this, the
# window would open and close instantly.
root.mainloop()