1.Import Required Libraries

import tkinter as tk
from tkinter import messagebox

• tkinter: Used to create the GUI (window, labels, buttons, text entry, output box).

• messagebox: Provides popup dialogs (used here for error handling).

2.Function: calculate_salary()

def calculate_salary():
    try:
        name = name_entry.get()
        emp_id = id_entry.get()
        basic = float(basic_entry.get())

• Fetches user inputs: name, employee ID, and basic salary.

• Converts salary to float for calculation.

        hra = 0.20 * basic
        da = 0.10 * basic
        pf = 0.05 * basic
        gross = basic + hra + da
        net = gross - pf

• Calculates:

  • HRA (House Rent Allowance) = 20% of basic

  • DA (Dearness Allowance) = 10% of basic

  • PF (Provident Fund) = 5% of basic

  • Gross Pay = basic + hra + da

  • Net Salary = gross – pf

        output = f"""
         PAYROLL SUMMARY 

         Name       : {name}
         Employee ID: {emp_id}
        ----------------------------------
         Basic Pay  : ₹{basic:.2f}
         HRA (20%)  : ₹{hra:.2f}
         DA (10%)   : ₹{da:.2f}
         PF (5%)    : ₹{pf:.2f}
        ----------------------------------
         Gross Pay  : ₹{gross:.2f}
         Net Salary : ₹{net:.2f}
        """

• Uses f-string formatting with emojis to display a well-formatted salary slip.

• :.2f limits all values to 2 decimal places.

        result_box.config(state='normal')
        result_box.delete(1.0, tk.END)
        result_box.insert(tk.END, output)
        result_box.config(state='disabled')

• Clears previous result, inserts new output, and disables editing of result box.

    except ValueError:
        messagebox.showerror("Invalid Input", "Basic Salary must be a number.")

• If the basic salary is not a number, a pop-up error is shown.

3.GUI Window Setup

root = tk.Tk()
root.title("Payroll Management System")
root.geometry("520x540")
root.configure(bg="#f0f8ff")

• Initializes main window with title, fixed size, and light blue background.

4.Header Label

tk.Label(root, text="Payroll Management System", font=("Helvetica", 18, "bold"), bg="#f0f8ff", fg="#0a3d62").pack(pady=20)

• Adds the main heading with bold font and dark text.

5.Input Frame and Fields

frame = tk.Frame(root, bg="#f0f8ff")
frame.pack()

• Creates a container frame to hold the input labels and fields.

tk.Label(frame, text=" Employee Name:", ...).grid(...)
name_entry = tk.Entry(frame, ...)

• Creates label and entry for employee name.

• Similar lines follow for employee ID and basic salary.

6.Calculate Button

tk.Button(root, text=" Calculate Salary", command=calculate_salary, bg="#27ae60", fg="white", ...).pack(pady=15)

• Green button that calls calculate_salary() when clicked.

7.Result Box (Text Widget)

result_box = tk.Text(root, height=15, width=60, font=("Courier New", 11), bd=2, relief="solid", bg="#fffafa")
result_box.pack(padx=20, pady=10)
result_box.config(state='disabled')

• A styled Text widget to display output.

• Courier New gives it a typewriter effect.

• Disabled by default to prevent editing.

8.Run the App

root.mainloop()

• Starts the Tkinter event loop and displays the window until it is closed.

 9.Summary of What It Does:

• Accepts input: name, ID, basic salary

• Calculates HRA, DA, PF, Gross, Net salary

• Displays a formatted, color-styled payslip in the output box

• Handles non-numeric input with error popups