7. Add Orders

../_images/pizza_6.png

  • Objective: Add functionality to add orders.

  • Content:

    • Creating an add order button.

    • Writing the add_order function.

    • Validating input and updating the order list.

7.1. Creating an Add Order Button

Place the following code below the other widget code in Section "4. TKINTER WIDGETS".
This code creates a button labeled "Add Order" that, when clicked, will call the add_order function to process the current order details.
# Add order button
add_button = tk.Button(root, text="Add Order", command=add_order,width=15)
add_button.grid(row=6, column=1, padx=10, pady=15, ipady=5, sticky="w")

  • tk.Button(root, text="Add Order", command=add_order, bg=button_bg, fg=button_fg): Creates a button with the text "Add Order" and assigns the add_order function to be called when the button is clicked.

  • .grid(row=6, column=1, padx=10, pady=10, ipadx=20, ipady=10, sticky="w"): Positions the button in the grid layout.

7.2. Importing messagebox

Add an import line for the messsagebox that is needed if no customer name is entered.
from tkinter import messagebox

7.3. Adding an Orders List

Place the following code below the code in Section "# 1. DATA DICTIONARIES & LISTS".
Add a list variable, orders, to keep track of orders.
Orders will be added as tuples of (customer, pizza, size, quantity).
Place this near the top of the code under the dictionaries or constants, before the definitions.
# Orders tracking list
orders = []

7.4. Writing the add_order Function

Place the following code in Section "3. DEFINITIONS / FUNCTIONS".
This function, add_order, is responsible for validating input and adding the current selection to the order list.
It retrieves the customer name, pizza type, size, and quantity from the respective widgets.
If the customer name is not entered, it shows an error message and highlights the entry field.
If the input is valid, it adds the order to the list and resets the quantity to 0.
def add_order():
    """Validates input and adds the current selection to the order list."""
    customer = customer_entry.get()
    pizza = pizza_var.get()
    size = size_var.get()
    quantity = quantity_var.get()

    if not customer:
        messagebox.showerror("Input Error", "Please enter the customer name.")
        customer_entry.config(bg="pink")
    else:
        customer_entry.config(bg="white")
        orders.append((customer, pizza, size, quantity))
        quantity_var.set(1)  # Reset quantity to default

  • add_order: Function to add an order to the list.

  • customer = customer_entry.get(): Retrieves the customer name from the entry widget.

  • pizza = pizza_var.get(): Retrieves the selected pizza type.

  • size = size_var.get(): Retrieves the selected pizza size.

  • quantity = quantity_var.get(): Retrieves the selected quantity string as an integer.

  • messagebox.showerror("Input Error", "Please enter the customer name."): Displays an error message if the customer name is not entered.

  • orders.append((customer, pizza, size, quantity)): Adds the order to the list of orders.

  • quantity_var.set("0"): Resets the quantity to 0.