GIDNetwork > Simple Python Inventory Program
Register
« GIDWebhosts Status: Alpha II Still working on the BBCodes II... »

Simple Python Inventory Program

by: crystalattice - Dec 14, 2006

Well, it's been a while since I posted anything about Python. I completed my BS in Computer Engineering and I'm working on my MS in IT Management, so not a lot of spare time lately.

The main thing I've been working on the last few weeks has been making an inventory system for my wife's business. She currently uses a spreadsheet to create her price lists and inventory, but she has to manually create an order form in email every time she buys new things (she's a consultant for a friend's home business, so no one has spent money on a real ordering system yet).

I thought I'd be nice and make a program that combines the features of a price sheet/inventory tracker that can also automatically create an order and email it. It would give me good pratice in programming, better knowledge of Python, and hopefully be easier to use by less-computer savvy people.

So, the program I wrote only took about 16 hours to write, which is pretty good since I still consider myself an intermediate programmer, plus I haven't messed a whole lot with GUI creation.

It uses shelves, which is basically a dictionary of dictionaries (or, for you C programmers, a mapping of mappings), which functions as a quick-and-dirty database. Since I didn't need to do serious SQL queries and other heavy DB things, shelves are good enough and they're built into the Python language.

I also used Tkinter, which is the standard GUI library included with Python. It's the first "large" program I've written in Tkinter; I've never tried anything with multiple windows and many different widgets before. It's a simple library, which can be limiting (I ran into problems creating the inventory display), but it's fine for a good chunk of GUI work.

My next task is to create a program that can call the current price list and allow the user to pick the items to order, then automatically create a formatted list, put it in an email, and send it. I'm also going to try and learn PyQt, since it's rated as the best cross-platform GUI designer. And I have to figure out how to let the program actually send the inventory list to the printer. All in all it's a constructive bit of "fluff" for me to work on.

Here's the main code, in all it's glory. You might notice that I included a lot of comments and doc strings that don't normally show up in the Python programs you'll find online. The triple-quoted doc strings are actually recommended by Guido Rossum (the Python creator) and are parsed automatically by PyDoc to create documentation (similar to man pages). I absolutely hate uncommented code, especially if I'm trying to figure out what's going on, so I do my best to self-document my code.

If you have any questions about how it all works, just ask.

Python Code Example:

################################################################################
#MPPInventory.py
#
#Purpose:  An inventory database interface for adding and modifying product
#   information.
#
#Author:  Cody Jackson
#Date:  12/1/06
#
#Copyright 2006 Cody Jackson
#This program is free software; you can redistribute it and/or modify it 
#under the terms of the GNU General Public License as published by the Free 
#Software Foundation; either version 2 of the License, or (at your option) 
#any later version.
#
#This program is distributed in the hope that it will be useful, but 
#WITHOUT ANY WARRANTY; without even the implied warranty of 
#MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 
#General Public License for more details.
#
#You should have received a copy of the GNU General Public License 
#along with this program; if not, write to the Free Software Foundation, 
#Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
#----------------------------------------------------------------------
#Version 0.4
#   Added ability to update product entry
#   Removed button instructions
#Version 0.3
#   Added MultiListbox class for inventory display
#   Removed text box display area
#   Updated display area methods to work with MultiListbox
#Version 0.2
#   Added "Delete Item" functionality
#   Added instructions
#   Added text box scrollbar
#Version 0.1
#   Initial build
######################################################################
#TODO: sort items by product number
#TODO: add printing ability

#!/usr/bin/env python

from Tkinter import *
from tkMessageBox import *
from quitter import Quitter
from MultiListBox import MultiListbox
import shelve

shelvename = "inventory.slv"

class ProductEntry(Frame):
    """Interface for product entry."""
    
    def __init__(self, parent = None):
        """Create, pack, and bind entry boxes and buttons for product entry."""
        
        Frame.__init__(self)
        self.pack()
        self.master.title("Product Inventory Entry")
        
        #---Instructions
        self.instructionFrame = Frame(self)
        self.instructionFrame.pack()
        
        Label(self.instructionFrame, text = "Enter the product information below.  Each product number must be unique.").pack()
        
        #---Entry boxes and column headers
        self.entryFrame = Frame(self)
        self.entryFrame.pack()
        
        #---Column headings
        self.col1 = Label(self.entryFrame, text = "Product Number")
        self.col1.grid(row = 0, column = 0)
        
        self.col2 = Label(self.entryFrame, text = "Description")
        self.col2.grid(row = 0, column = 1)
        
        self.col3 = Label(self.entryFrame, text = "Color")
        self.col3.grid(row = 0, column = 2)
        
        self.col4 = Label(self.entryFrame, text = "Unit cost")
        self.col4.grid(row = 0, column = 3)
        
        self.col5 = Label(self.entryFrame, text = "Selling price")
        self.col5.grid(row = 0, column = 4)
        
        self.col6 = Label(self.entryFrame, text = "Quantity")
        self.col6.grid(row = 0, column = 5)
        
        #---Entry boxes
        self.prodNum = Entry(self.entryFrame, name = "prodNum")
        self.prodNum.grid(row = 1, column = 0)
        
        self.description = Entry(self.entryFrame, name = "description")
        self.description.grid(row = 1, column = 1)
        
        self.color = Entry(self.entryFrame, name = "color")
        self.color.grid(row = 1, column = 2)
        
        self.userCost = Entry(self.entryFrame, name = "cost")
        self.userCost.grid(row = 1, column = 3)
        
        self.sellPrice = Entry(self.entryFrame, name = "price")
        self.sellPrice.grid(row = 1, column = 4)
        
        self.quantity = Entry(self.entryFrame, name = "quantity")
        self.quantity.grid(row = 1, column = 5)
        
        #---Product entry buttons
        self.entryBtnFrame = Frame(self)
        self.entryBtnFrame.pack()
        
        self.newEntryBtn = Button(self.entryBtnFrame, text = "Enter product",
            command = self.clickNewEntry)
        self.newEntryBtn.pack(side = LEFT)
        
        ##Imported quit button
        Quitter(self.entryBtnFrame).pack(side = LEFT)
    
    def clickNewEntry(self):
        """Get all entry boxes and write to inventory database."""
        
        self.key = self.prodNum.get()
        self.record = [self.description.get(), self.color.get(),
            self.userCost.get(), self.sellPrice.get(), self.quantity.get()]
        self.writeShelf(self.key, self.record)
        
        #clear data fields
        self.prodNum.delete(0, END)
        self.description.delete(0, END)
        self.color.delete(0, END)
        self.userCost.delete(0, END)
        self.sellPrice.delete(0, END)
        self.quantity.delete(0, END)
    
    def writeShelf(self, key, record):
        """Opens DB, writes entries, then closes DB."""
        
        self.database = shelve.open(shelvename)
        self.database[self.key] = self.record
        self.database.close()
    
class ProductDisplay(Frame):
    """Interface for product display"""
    
    def __init__(self, parent = None):
        """Create, pack, and bind entry boxes and buttons for product display"""
        
        Frame.__init__(self)
        self.pack()
        
        self.frameHeading = Frame(self)
        self.frameHeading.pack()
        
        self.frameHeadingTitle = Label(self.frameHeading, text = "Current inventory",
            font = ("Arial", "12", "bold"))
        self.frameHeadingTitle.pack()      
        
        #---Database output
        self.showInventoryFrame = Frame(self).pack()
        
        ##Imported table-like multilist box
        self.listBox = MultiListbox(self.showInventoryFrame, (("Product Number", 10), 
            ("Description", 40), ("Color", 10), ("Unit cost", 5), ("Sell price", 5)
            , ("Quantity", 5)))
        self.listBox.pack(expand = YES, fill = BOTH)
        
        #---Inventory display buttons
        self.inventoryBtnFrame = Frame(self).pack()
        self.fetchInven = Button(self.inventoryBtnFrame, text = "Get inventory",
            command = self.getInven)
        self.fetchInven.pack(side = LEFT)
        
        self.modifyInven = Button(self.inventoryBtnFrame, text = "Update listing",
            command = self.changeInven)
        self.modifyInven.pack(side= LEFT)
        
        self.deleteInven = Button(self.inventoryBtnFrame, text = "Delete entry",
            command = self.clearEntry)
        self.deleteInven.pack(side = LEFT)
        
        self.clearInven = Button(self.inventoryBtnFrame, text = "Clear inventory",
            command = self.delInven)
        self.clearInven.pack(side = LEFT)
    
    def getInven(self):
        """Gets products from DB and displays them.
        
        Opens the shelve, loops through each entry, prints the unpacked tuple
        for each record, then closes the shelve."""
        self.listBox.delete(0, END)
        self.productList = shelve.open(shelvename)
        for item in self.productList.keys():
            (self.descrip, self.colors, self.cost, self.price, 
                self.quan) = self.productList[item]    #unpack tuple
            self.listBox.insert(END, (item, self.descrip, self.colors, self.cost,
                self.price, self.quan))
        self.productList.close()
    
    def clearEntry(self):
        """Deletes an entry from the database.
        
        Gets the highlighted selection, makes a list of the the separate words,
        'pops' the product number entry, finds the product number in the shelve,
        deletes the product, then updates the inventory screen."""
        
        ans = askokcancel("Verify delete", "Really remove item?")   #popup window
        if ans:
            self.productList = shelve.open(shelvename)
            self.getSelection = self.listBox.curselection() #get index of selection
            self.selectedEntry = self.listBox.get(self.getSelection)    #get tuple from selection
            (self.productNum, self.descrip, self.colors, self.cost, self.price, 
                self.quan) = self.selectedEntry    #unpack tuple
            self.entry = self.selectedEntry[0]
            del self.productList[self.entry]
            self.productList.close()
            showinfo(title = "Product removed",
                message = "The product has been removed from inventory.")
            self.getInven()

    def changeInven(self):
        """Allows modification of a database entry.
        
        Called by modifyInven Button"""
        
        try:    #see if a selection was made
            self.getSelection = self.listBox.curselection() #get index of selection
            self.selectedEntry = self.listBox.get(self.getSelection)    #get tuple from selection
            (self.prodnum, self.descrip, self.colors, self.cost, self.price, 
                self.quan) = self.selectedEntry    #unpack tuple
            
            #---New 'edit product' window
            self.editWindow = Toplevel()    
            self.editWindow.title("Edit selected entry")
            
            #---Edit product window widgets
            Label(self.editWindow, text = "Product Number").grid(row = 0, column = 0)
            Label(self.editWindow, text = "Description").grid(row = 0, column = 1)
            Label(self.editWindow, text = "Color").grid(row = 0, column = 2)
            Label(self.editWindow, text = "Unit cost").grid(row = 0, column = 3)
            Label(self.editWindow, text = "Sell price").grid(row = 0, column = 4)
            Label(self.editWindow, text = "Quantity").grid(row = 0, column = 5)
            
            self.oldNum = Entry(self.editWindow, name = "prodNum")
            self.oldNum.grid(row = 1, column = 0)
            self.oldDescrip = Entry(self.editWindow, name = "descrip")
            self.oldDescrip.grid(row = 1, column = 1)
            self.oldColor = Entry(self.editWindow, name = "color")
            self.oldColor.grid(row = 1, column = 2)
            self.oldCost = Entry(self.editWindow, name = "cost")
            self.oldCost.grid(row = 1, column = 3)
            self.oldPrice = Entry(self.editWindow, name = "price")
            self.oldPrice.grid(row = 1, column = 4)
            self.oldQuan = Entry(self.editWindow, name = "quan")
            self.oldQuan.grid(row = 1, column = 5)
            
            self.update = Button(self.editWindow, text = "Update product",
                command = self.updateProduct).grid(row = 2, column = 2)
            self.cancel = Button(self.editWindow, text = "Cancel",
                command = self.cancelProduct).grid(row = 2, column = 3) 
           
            #---Edit product data
            self.oldNum.insert(END, self.prodnum)
            self.oldDescrip.insert(END, self.descrip)
            self.oldColor.insert(END, self.colors)
            self.oldCost.insert(END, self.cost)
            self.oldPrice.insert(END, self.price)
            self.oldQuan.insert(END, self.quan)
            
        except TclError:    #tell user to make a selection first
            showerror(title = "Error!", message = "You must make a selection first!")
    
    def updateProduct(self):
        """Change the values of a database entry.
        
        Called by changeInven Button."""
        
        self.productList = shelve.open(shelvename)
        self.oldEntry = self.oldNum.get()
        self.newQuan = self.oldQuan.get()
        self.newCost = self.oldCost.get()
        self.newPrice = self.oldPrice.get()
        self.newRecord = [self.descrip, self.colors,
            self.newCost, self.newPrice, self.newQuan]
        self.productList[self.oldEntry] = self.newRecord
        self.productList.close()
        self.editWindow.destroy()
    
    def cancelProduct(self):
        """Verify canceling of product update."""
        
        self.editWindow.destroy()
    
    def delInven(self):
        """Deletes all entries in database."""
        
        ans = askokcancel("Verify delete", "Really clear inventory?")   #popup window
        if ans: 
            self.productList = shelve.open(shelvename)
            self.productList.clear()
            self.productList.close()
            showinfo(title = "Inventory cleared",
                message = "Your inventory database has been deleted.")

def main():
    root = Tk()
    entry = ProductEntry(root)
    display = ProductDisplay(root)
    entry.pack()
    display.pack()
    root.mainloop()
    
if __name__ == "__main__":
    main()
Would you like to comment? This story has been viewed 38,301 times.
« GIDWebhosts Status: Alpha II Still working on the BBCodes II... »

__top__

Copyright © GIDNetwork™ 2001 - 2017

Another website by J de Silva

Page generated in : 0.04422 sec.