An expense tracker is an essential tool that helps individuals and businesses manage their financial transactions. With an expense tracker, you can create budgets, categorize expenses, and analyze spending patterns.
Find out how to build an expense tracker app, with a cross-platform GUI, in Python.
The Tkinter, CSV, and Matplotlib Modules
To build this expense tracker, you’ll need the Tkinter, CSV, and Matplotlib modules.
Tkinter lets youcreate desktop applications. It offers a variety of widgets like buttons, labels, and text boxes that make it easy to develop apps.
The CSV module is a built-in Python library that provides functionality for reading and writingCSV (Comma-Separated Values) files.
With Matplotlib, you can build interactive visualizations such as graphs, plots, and charts. Using it with modules like OpenCV can help youmaster image enhancement techniquestoo.
To install these modules, run:
Define the Structure of the Expense Tracker App
You can find this project’s source code in itsGitHub repository.
Begin by importing the necessary modules. Define a class,ExpenseTrackerApp. Set the title and the dimensions. Define a list to store the expenses and another for the categories. Initialize aStringVarnamedcategory_varand set its initial value to the first category in the categories list. Finish up by calling thecreate_widgetsmethod.
Thecreate_widgetsmethod is responsible for adding UI components to your app. Create a frame for the expense record’s labels and entries. Create six labels: one each for the heading, expense amount, item description, category, date, and total expense. Set each one’s parent element, the text it should display, and its font style.
Create three entry widgets and aComboboxto get the corresponding input. For the entry widgets, set the parent element, the font style, and the width. Define the parent element, the list of values, the font style, and the width for theCombobox. Bindcategory_varto it, so the selected value is automatically updated.
Define five buttons:Add Expense,Edit Expense,Delete Expense,Save Expenses, andShow Expenses Chart. Set the parent element of each, the text it should display, and the command it will run when you click it. Create a frame for the listbox. Set the parent element, the font style, and the width.
Create a vertical scroll bar and place it on the right side of the frame. Use it to scroll through the contents of the listbox. Organize all the elements with necessary padding and callupdate_total_label().
Define the Functionality of the Expense Tracker
Define a method,add_expense. Retrieve the value of the expense, item, category, and date. If the value of the expense and date are valid, add the expense to theexpenseslist. Insert this record into the listbox and format it appropriately. Once inserted, delete the user input in the entry boxes for new input.
Otherwise, display a warning that the values of expense and date cannot be empty. Callupdate_total_label.
Define a method,edit_expense. Retrieve the index of the selected record and get the expense. Open a dialog box asking to enter the expense. If the user provided a new expense, alter the expenses list accordingly. Call therefresh_listandupdate_total_label.
Define a method,delete_expense. Retrieve the index of the selected record and get the expense. Pass the index of the entry you want to delete. Delete that entry from the listbox and call theupdate_total_label.
Define a method,refresh_list. Delete the existing record and add a new record with the updated values instead.
Define a method,update_total_label. Calculate the sum of all expenses in the list and update it on the label. Define another method,save_expenses. Create and open aCSVfile namedexpenses.csvin write mode. Add column headers to the CSV file as the first row. Iterate over each expense record, and write it as a row.
Define a method,show_expenses_chart. Define a dictionary,category_totals. Iterate through theexpenseslist and convert the expense amount to float. Store the total expense amount for each category. If the category already exists in the dictionary, increment the total by the current expense amount. Otherwise, create a new entry with the current expense amount.
Extract the categories and the expenses into two different lists. Create a new figure for the plot with the specified size. Generate a pie chart, using the expenses list as the data and the category list as the label. Theautopctparameter specifies the format for displaying the percentage values on the chart slices. Passequaltoplt.axisto ensure that you draw the pie chart as a circle. Set the title of the pie chart and display it.
Create an instance of theExpenseTrackerAppclass. Themainloop()function tells Python to run the Tkinter event loop and listen for events until you close the window.
Test Different Features of the Python Expense Tracker
When you run the program, it will launch an application window. This has input fields to record the expense, the item description, the category, and the date. Enter some data and click theAdd Expensebutton; you’ll see the record gets added to the list box. The program also updates the total expenses.
Select a record and click theEdit Expensesbutton. A dialog box appears, letting you update the individual record.
Clicking theDelete Expensesbutton to remove the selected record.
On hitting theShow Expenses Chartbutton, the program displays a pie chart. The pie chart displays the expense for each category along with its name and percentage.
Improving the Expense Tracker
You can add search functionality to let users find specific expenses based on their description, amount, category, or date. You can add an option to sort and filter records. Localize the app to support different languages and currency formats.
You could also extend the app with support for notifications. Let the user set up alerts to prevent them from exceeding budget limits or highlight any unusual spending.
