Using Combobox and Entry for item billing in Restaurant Management

Restaurant Management using Combobox and Entry

Using Combobox to select item and Entry for quantity in Restaurant Management script in Tkinter

Using Combobox for selection of items

We are using one Combobox and showing all items as options. One Entry widget is placed by the side of this combobox so user can enter the quantity of the selected item.

Data is taken from MySQL database product table based on the selection of the radio button ( product category) . This radio button is used to filter any particular category of product from the large number of products in the plus2_products table.

We kept the function to display all items inside one function show_item(). This function receives the category as parameter and filters the product items ( p_cat ) based on the query.

Add button is placed to trigger the function my_add() to insert the selected item to bill.

def show_items(cat): # Populating the Combobox 
    global my_menu,my_menu2
    my_menu.clear() # remove all items
    cb1.set('')
    e1.delete(0,END)
    r_set=my_conn.execute("SELECT * FROM plus2_products WHERE \
       available=1 and  p_cat="+str(cat))
    
    for item in r_set:
        my_menu.update({item[0]:item[1]}) 
        my_menu2.update({item[1]:[item[0],item[1],item[3]]})
    options=list(my_menu.values())
    cb1.config(values=options)
    b1=tk.Button(frame_m_left,text='Add',font=font2,
     command=lambda:my_add())
    b1.grid(row=0,column=2,padx=10)
show_items(1)

Adding selected item and quanity to bill

Here try and except code block is used for checking the valid inputs and then adding them to Treeview ( trv ) . The object trv ( Treeview ) is declared outside at the main script so it is available to all functions.

The function my_sum() is called to calculate the total including the tax part.

After inserting the data to treeview the Combobox and entry widget is reset to accept fresh selection.

def my_add(): #adding item to bill 
    try:
        p_id=my_menu2[sel.get()][0]
        p_name=sel.get()
        price=e1.get()
        quantity=my_menu2[sel.get()][2]
    except:
        return None 
    if(int(quantity)>0 and len(p_name)>0 and p_id>0):
        sub_total=round(float(price)*int(quantity),2)
        trv.insert("",'end',text=p_id,values=[p_name,price,quantity,sub_total])
        my_sum() # re-calculate the total 
        cb1.set('') # reset the combobox
        e1.delete(0,END)# reset the entry widget

Calculating the total and bill

To calculate the total value, tax and to show the final price, we kept the code in a separate function my_sum(). This function is called when we add any item or remove some item ( next part ) or finalize the bill.

The for loop inside the function collects the total value of each node or child ( line ) and add them.

After calculating the tax, total value by looping , we used config() to change the text on Labels to display the values.

def my_sum(): # Calculate total and tax part 
    total=0
    for line in trv.get_children(): # Loop through all items
        total=total+float(trv.item(line)['values'][3])
    tax=round(0.1*total,2)   # change the tax rate here 
    final=round(total+tax,2) # final price 
    lr2.config(text=str(total)) # show it at Label 
    lr22.config(text=str(tax))  # show it at Label
    lr32.config(text=str(final))# show it at Label

Reset the bill

This function is triggered by the Button saying Confirm ( Reset). This will prepare for next bill and we can include the script to insert the data to our table at this stage.

def my_reset():
    for item in trv.get_children(): # loop all child items 
        trv.delete(item)        # delete them 
    my_sum() # call the re-calculate and update the labels text

Database tables

All table details ( SQL dump ) and installation is discussed in previous sections.
MySQL Installing
MySQL Connecting string
MySQL connection using SQLAlchemy

Full code is here

import tkinter as tk
from tkinter import *
from tkinter import ttk
from tkinter import BOTH, END, LEFT
from my_connect import my_conn # database connection

font1=('Times',14,'normal')
font2=('Times',32,'bold')
my_w = tk.Tk()
my_w.geometry("1000x800")

my_w.columnconfigure(0,weight=4)
my_w.columnconfigure(1,weight=2)
my_w.rowconfigure(0, weight=1) 
my_w.rowconfigure(1, weight=14) # change weight to 4
my_w.rowconfigure(2, weight=2)

frame_top=tk.Frame(my_w,bg='white')
frame_bottom=tk.Frame(my_w,bg='white')

frame_m_right=tk.Frame(my_w,bg='#f8fab4')
frame_m_left=tk.Frame(my_w,bg='#284474')

#placing in grid
frame_top.grid(row=0,column=0,sticky='WENS',columnspan=2)
frame_m_left.grid(row=1,column=0,sticky='WENS')
frame_m_right.grid(row=1,column=1,sticky='WENS')
frame_bottom.grid(row=2,column=0,sticky='WENS',columnspan=2)
trv = ttk.Treeview(frame_m_right, selectmode ='browse')
trv.grid(row=0,column=0,columnspan=2,padx=3,pady=2)

# column identifiers 
trv["columns"] = ("1", "2","3","4")
trv.column("#0", width = 40, anchor ='w')
trv.column("1", width = 100, anchor ='w')
trv.column("2", width =50 , anchor ='w')
trv.column("3", width = 50, anchor ='w')
trv.column("4", width = 80, anchor ='w')
  
# Headings  
# respective columns
trv.heading("#0", text ="id",anchor='w')
trv.heading("1", text ="name",anchor='w')
trv.heading("2", text ="qty",anchor='w')
trv.heading("3", text ="price",anchor='w')
trv.heading("4", text ="Total",anchor='w')
def my_reset():
    for item in trv.get_children(): # loop all child items 
        trv.delete(item)        # delete them 
    my_sum() # call the re-calculate and update the labels text
# Layout is over , sart placing buttons 
path_image="G:\\My Drive\\testing\\plus2_restaurant_v1\\images\\"
img_top = tk.PhotoImage(file = path_image+"restaurant-3.png")
#bg=tk.PhotoImage(file=path_image+'bg2.png')

img_l1 = tk.Label(frame_top,  image=img_top)
img_l1.grid(row=0,column=0,sticky='nw',pady=1)

sel=tk.StringVar() # string variable for the Combobox
cb1=ttk.Combobox(frame_m_left,width=15,
    textvariable=sel,font=font2)
cb1.grid(row=0,column=0,padx=10, pady=20) 
e1=tk.Entry(frame_m_left,width=4,font=font2)   
e1.grid(row=0,column=1)

lr1=tk.Label(frame_m_right,text='Total',font=font1)
lr1.grid(row=1,column=0,sticky='nw')
lr2=tk.Label(frame_m_right,text='',font=font1)
lr2.grid(row=1,column=1,sticky='nw')
lr21=tk.Label(frame_m_right,text='Tax 10%',font=font1)
lr21.grid(row=2,column=0,sticky='nw')

lr22=tk.Label(frame_m_right,text='',font=font1)
lr22.grid(row=2,column=1,sticky='nw')
lr31=tk.Label(frame_m_right,text='Total',font=font2)
lr31.grid(row=3,column=0,sticky='nw')

lr32=tk.Label(frame_m_right,text='',font=font2)
lr32.grid(row=3,column=1,sticky='nw')

def my_sum(): # Calculate total and tax part 
    total=0
    for line in trv.get_children(): # Loop through all items
        total=total+float(trv.item(line)['values'][3])
    tax=round(0.1*total,2)   # change the tax rate here 
    final=round(total+tax,2) # final price 
    lr2.config(text=str(total)) # show it at Label 
    lr22.config(text=str(tax))  # show it at Label
    lr32.config(text=str(final))# show it at Label 
def my_add(): #adding item to bill 
    try:
        p_id=my_menu2[sel.get()][0]
        p_name=sel.get()
        price=e1.get()
        quantity=my_menu2[sel.get()][2]
    except:
        return None 
    if(int(quantity)>0 and len(p_name)>0 and p_id>0):
        sub_total=round(float(price)*int(quantity),2)
        trv.insert("",'end',text=p_id,values=[p_name,price,quantity,sub_total])
        my_sum() # 
        cb1.set('')
        e1.delete(0,END)
my_menu2={}
my_menu={} # Dictionary to store items with price
def show_items(cat): # Populating the Combobox 
    global my_menu,my_menu2
    my_menu.clear() # remove all items
    cb1.set('')
    e1.delete(0,END)
    r_set=my_conn.execute("SELECT * FROM plus2_products WHERE \
       available=1 and  p_cat="+str(cat))
    
    for item in r_set:
        my_menu.update({item[0]:item[1]}) 
        my_menu2.update({item[1]:[item[0],item[1],item[3]]})
    options=list(my_menu.values())
    cb1.config(values=options)
    b1=tk.Button(frame_m_left,text='Add',font=font2,
     command=lambda:my_add())
    b1.grid(row=0,column=2,padx=10)
show_items(1)
r1_v = tk.IntVar(value=1) # We used integer variable here

r1 = tk.Radiobutton(frame_bottom, text='Breakfast', variable=r1_v, value=1,command=lambda:show_items(1))
r1.grid(row=0,column=0)

r2 = tk.Radiobutton(frame_bottom, text='Lunch', variable=r1_v, value=0,command=lambda:show_items(2))
r2.grid(row=0,column=1)

r3 = tk.Radiobutton(frame_bottom, text='Dinner', variable=r1_v, value=5,command=lambda:show_items(3))
r3.grid(row=0,column=2)

b2=tk.Button(frame_bottom,text='Confirm ( Reset)',command=my_reset)
b2.grid(row=0,column=4,padx=10)
my_w.mainloop()

Restaurant Management V-1 Restaurant Management V-2
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Using Combobox for item selection in Restaurant Management System