8. Display Orders

• Objective: Display the list of orders.

• Content:

  • Adding a Listbox widget to display orders.

  • Formatting the orders display.

  • Updating the orders list dynamically.

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8.1. Adding a Listbox Widget to Display Orders

Place the following code below the other widget code in Section "4. TKINTER WIDGETS".

This code creates a Listbox widget for displaying orders.

# --- RIGHT SIDE: ORDER DISPLAY & MANAGEMENT ---

# Order List Label & Listbox
orders_label = tk.Label(root, text="Current Orders:")
orders_label.grid(row=0, column=2, padx=10, pady=5, sticky="w")

order_list = tk.Listbox(root, width=45, height=12)
order_list.grid(row=1, column=2, rowspan=5, columnspan=2, padx=10, pady=5, sticky="nsew")

• orders_label = tk.Label(root, text="Current Orders:"): Creates a label widget with the text "Current Orders:".

• orders_label.grid(row=0, column=2, padx=10, pady=5, sticky="w"): Positions the label widget in the grid layout.

• order_list = tk.Listbox(root, width=45, height=12): Creates a Listbox widget to display the list of orders.

• order_list.grid(row=1, column=2, rowspan=5, columnspan=2, padx=10, pady=5, sticky="nsew"): Positions the Listbox widget in the grid layout.

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8.2. Display the orders as a list

Place the following code in Section "3. DEFINITIONS / FUNCTIONS".

This function, update_order_list, is responsible for displaying the current list of orders in the order_list Listbox widget.

It first clears the Listbox, then iterates through the orders list, calculating the cost for each order and inserting a formatted string into the Listbox.

Finally, it calculates and displays the total cost of all orders at the end of the Listbox.

# Display orders
def update_order_list():
    order_list.delete(0, tk.END)
    total_cost = 0

    for order in orders:
        customer, pizza, size, quantity = order
        cost = prices[pizza][size] * quantity
        total_cost += cost
        order_list.insert(tk.END, f"{customer} - {quantity} {size} {pizza} - ${cost}")
    if orders:
        order_list.insert(tk.END, f"Total cost: ${total_cost}")

• order_list.delete(0, tk.END): Clears the Listbox widget.

• order_list.insert(tk.END, f"{customer} - {quantity} {size} {pizza} - ${cost}"): Inserts the formatted order details into the Listbox widget.

• order_list.insert(tk.END, f"Total cost: ${total_cost}"): Inserts the total cost at the end of the Listbox.

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8.3. Updating the Orders List Dynamically

Place the following code in Section "3. DEFINITIONS / FUNCTIONS".

This code updates the orders list dynamically when an order is added.

• Call update_order_list() whenever an order is added.

• Add the code line below to the bottom of the else block in add_order().

# add to add_order()
update_order_list()