GUI Calculator Using Tkinter In Python

assignment advertisement

We will make a Simple GUI Calculator Using Tkinter In Python which is a python module to make GUI applications simply so that’s why we will use it to make a GUI Calculator Using tkinter

Here we are going to provide you with the source code with a complete explanation so that you can easily make your GUI Calculator Using tkinter

Source Code

# importing the tkinter module
from tkinter import *

# initializing the tkinter
root = Tk()

# setting the width and height of the gui
root.geometry("430x500")    # x is small case here

# declaring an empty string variable
expression = ""

# defining function which will set expressions and answers to the  user
def setexpression(num):
    global expression
    expression = expression + str(num)

# defining a function to calculate the expression entered by the user
def calculator():
        global expression
        answer = str(eval(expression))
        value.set("Enter correct expression")
        expression = ""

# function to clear everything in expression
def clear():
    global expression
    expression = ""

# declaring font variables as ("Language", size)
large_font = ('Verdana', 15)
small_font = ('Verdana', 10)

# declaring variable to take value of expression entered by the user
value = StringVar(value="Enter expression")

# entry widget to take expression from user and to show 
# calculations 
Entry(root, textvariable=value, font=large_font).grid(row=0, 
    column=0, columnspan=4, ipadx=70)

# Now, there are some most basic buttons which should be present 
# in a calculator
# here, each button is calling the setexpression function which 
# is used to set values in the entry widget entered by the user 
# on pressing the buttons 1, 2, 3, 4, 5, 6, 7, 8, 9, 0, .
Button(root, text="+", fg="red", command=lambda: 
    setexpression("+"), height=4,width=8).grid(row=1,column=0,pady=10)
Button(root, text="-", fg="red", command=lambda:
    setexpression("-"), height=4, width=8).grid(row=2, column=0, pady=10)
Button(root, text="X", fg="red", command=lambda: 
    setexpression("*"), height=4, width=8).grid(row=3, column=0,pady=10)
Button(root, text="/", fg="red", command=lambda: 
    setexpression("/"), height=4, width=8).grid(row=4, column=0,pady=10)
Button(root, text="1", fg="red", command=lambda: 
    setexpression("1"), height=4, width=8).grid(row=1, column=1,pady=10)
Button(root, text="2", fg="red", command=lambda: 
    setexpression("2"), height=4, width=8).grid(row=1, column=2,pady=10)
Button(root, text="3", fg="red", command=lambda: 
    setexpression("3"), height=4, width=8).grid(row=1, column=3,pady=10)
Button(root, text="4", fg="red", command=lambda: 
    setexpression("4"), height=4, width=8).grid(row=2, column=1,pady=10)
Button(root, text="5", fg="red", command=lambda: 
    setexpression("5"), height=4, width=8).grid(row=2, column=2)
Button(root, text="6", fg="red", command=lambda: 
    setexpression("6"), height=4, width=8).grid(row=2, column=3,pady=10)
Button(root, text="7", fg="red", command=lambda: 
    setexpression("7"), height=4, width=8).grid(row=3, column=1,pady=10)
Button(root, text="8", fg="red", command=lambda: 
    setexpression("8"), height=4, width=8).grid(row=3, column=2,pady=10)
Button(root, text="9", fg="red", command=lambda: 
    setexpression("9"), height=4, width=8).grid(row=3, column=3,pady=10)
Button(root, text="0", fg="red", command=lambda: 
    setexpression("0"), height=4, width=8).grid(row=4, column=2,pady=10)
Button(root, text=".", fg="red", command=lambda: 
    setexpression("."), height=4, width=8).grid(row=4, column=1,pady=10)

# "=" button to call the calculator button which will return and 
# show the calculated value in the entry widget
Button(root, text="=", fg="red", command=calculator, height=4,
width=8).grid(row=4, column=3, pady=10)

# "Clear" button to call the clear function which will clear the 
# entry widget so that the user can start clculating again
Button(root, text="Clear", fg="red", command=clear, height=4, 
    width=20).grid(row=5, column=1, pady=10)

# .mainloop() is used when the code is ready to run



Keep updated for more amazing content like this

Also read:


Author: Harry

Hello friends, thanks for visiting my website. I am a Python programmer. I, with some other members, write blogs on this website based on Python and Programming. We are still in the growing phase that's why the website design is not so good and there are many other things that need to be corrected in this website but I hope all these things will happen someday. But, till then we will not stop ourselves from uploading more amazing articles. If you want to join us or have any queries, you can mail me at Thank you