Tkinter arithmetic operator

Step 1: Import Tkinter module

from tkinter import *

• This imports everything from Tkinter, which is used to create the graphical user interface (GUI).

Step 2: Create the Main Window

b = Tk()
b.minsize(650, 250)
b.maxsize(650, 250)
b.title("Arithmetic Operator")

• b = Tk() creates the main window.

• b.minsize(650, 250) sets the minimum window size to 650×250 pixels.

• b.maxsize(650, 250) sets the maximum window size to 750×250 pixels.

• b.title("Arithmetic Operator") sets the title of the window

Step 3: Define functions for arithmetic operations

Each function retrieves numbers from the entry fields, performs calculations, and displays the result.

Addition function

def add():
    try:
        num1 = float(e1.get())
        num2 = float(e2.get())
        answer = num1+num2
        e3.delete(0, END)
        e3.insert(0, str(answer))
    except ValueError:
        e3.delete(0, END)
        e3.insert(0, "Invalid input")

Substraction function

def sub():
    try:
        num1 = float(e1.get())
        num2 = float(e2.get())
        answer = num1-num2
        e3.delete(0, END)
        e3.insert(0, str(answer))
    except ValueError:
        e3.delete(0, END)
        e3.insert(0, "Invalid input")

Multiplication function

def mult():
    try:
        num1 = float(e1.get())
        num2 = float(e2.get())
        answer = num1*num2
        e3.delete(0, END)
        e3.insert(0, str(answer))
    except ValueError:
        e3.delete(0, END)
        e3.insert(0, "Invalid input")

Division function

def div():
    try:
        num1 = float(e1.get())
        num2 = float(e2.get())
        if num2 ==0:
            e3.delete(0, END)
            e3.insert(0, "number can't divide by 0")
        answer = num1/num2
        e3.delete(0, END)
        e3.insert(0, str(answer))
    except ValueError:
        e3.delete(0, END)
        e3.insert(0, "Invalid input")

Step 4: Create Labels

These labels indicate where to enter numbers and where the answer will be displayed.

l1 = Label(b, text="1st number", font=("arial",15))
l1.place(x=10, y=20)
l2 = Label(b, text="2nd number", font=("arial",15))
l2.place(x=10, y=60)
l3 = Label(b, text="Answer", font=("arial",15))
l3.place(x=10, y=180)

• Label() creates a label with text.

• place(x, y) positions the label in the window.

Step 5: Create Entry Fields

Users enter numbers in these fields.

e1 = Entry(b, font=("arial",15))
e1.place(x=225, y=20)
e2 = Entry(b, font=("arial",15))
e2.place(x=225, y=60)
e3 = Entry(b, font=("arial",15))
e3.place(x=225, y=180)

• Entry() creates an input box where the user can type numbers.

• place(x, y) positions the entry fields.

Step 6: Create Buttons for Operations

Each button calls its respective function when clicked.

b1 = Button(b, text="add", font=("arial",15), command=add)
b1.place(x=50, y=120)
b2 = Button(b, text="subtract", font=("arial",15), command=sub)
b2.place(x=150, y=120)
b3 = Button(b, text="multiply", font=("arial",15), command=mult)
b3.place(x=320, y=120)
b4 = Button(b, text="divide", font=("arial",15), command=div)
b4.place(x=475, y=120)

• Button() creates a clickable button.

• command=add (or sub, mult, div) tells the button which function to execute when clicked.

• place(x, y) positions the buttons.

Step 7: Run the Main Event Loop

b.mainloop()

• This starts the Tkinter event loop, keeping the window open.

Complete Code

from tkinter import *

b = Tk()
b.minsize(650, 250)
b.maxsize(750, 250)
b.title("Arithmetic Operator")

def add():
    try:
        num1 = float(e1.get())
        num2 = float(e2.get())
        answer = num1+num2
        e3.delete(0, END)
        e3.insert(0, str(answer))
    except ValueError:
        e3.delete(0, END)
        e3.insert(0, "Invalid input")

def sub():
    try:
        num1 = float(e1.get())
        num2 = float(e2.get())
        answer = num1-num2
        e3.delete(0, END)
        e3.insert(0, str(answer))
    except ValueError:
        e3.delete(0, END)
        e3.insert(0, "Invalid input")

def mult():
    try:
        num1 = float(e1.get())
        num2 = float(e2.get())
        answer = num1*num2
        e3.delete(0, END)
        e3.insert(0, str(answer))
    except ValueError:
        e3.delete(0, END)
        e3.insert(0, "Invalid input")

def div():
    try:
        num1 = float(e1.get())
        num2 = float(e2.get())
        if num2 ==0:
            e3.delete(0, END)
            e3.insert(0, "number cannot divide by 0")
        answer = num1/num2
        e3.delete(0, END)
        e3.insert(0, str(answer))
    except ValueError:
        e3.delete(0, END)
        e3.insert(0, "Invalid input")

l1 = Label(b, text="1st number", font=("arial",15))
l1.place(x=10, y=20)
l2 = Label(b, text="2nd number", font=("arial",15))
l2.place(x=10, y=60)
l3 = Label(b, text="Answer", font=("arial",15))
l3.place(x=10, y=180)

e1 = Entry(b, font=("arial",15))
e1.place(x=225, y=20)
e2 = Entry(b, font=("arial",15))
e2.place(x=225, y=60)
e3 = Entry(b, font=("arial",15))
e3.place(x=225, y=180)

b1 = Button(b, text="add",font=("arial",15), command=add)
b1.place(x=50, y=120)
b2 = Button(b, text="subtract",font=("arial",15),command=sub)
b2.place(x=150, y=120)
b3 = Button(b, text="multiply",font=("arial",15), command=mult)
b3.place(x=320, y=120)
b4 = Button(b, text="divide",font=("arial",15),command=div)
b4.place(x=475, y=120)

b.mainloop()