Prerequisite: PySimpleGUI, eval
PySimpleGUI is a Python package that enables Python programmers of all levels to create GUIs. You specify your GUI window using a “layout” that contains widgets (they’re called “Elements” in PySimpleGUI). In this article, we will learn, how to make a calculator using PySimpleGUI in Python.
Before starting we need to install this package:
pip install PySimpleGUI
Approach:
- Import the PySimpleGUI Module
- Create GUI layout and Window
- Add any number of widgets to the main window
- Apply the event Trigger on the widgets.
Below is what the GUI looks like:
Let’s create a GUI-based simple calculator using the Python PySimpleGUI module, which can perform basic arithmetic operation’s addition, subtraction, multiplication, and division.
Let’s Understand step by step implementation:-
Step1: Create Text Box, Buttons
For creating a text box, we will use Txt() method.
Syntax: Txt(Enter Text, *attr)
Here will use the read button using ReadFormButton() method.
Syntax: ReadFormButton(Enter Button Text, *attr)
Step 2: Create an infinite loop, read the button value and perform the operation.
Python3
# Result Value Result = '' # Make Infinite Loop while True: # Button Values button, value = form.Read() # Check Press Button Values if button=='c': Result = '' form.FindElement('input').Update(Result) elif button=='«': Result = Result[:-1] form.FindElement('input').Update(Result) elif len(Result) == 16 : pass # Results elif button=='=': Answer = eval(Result) Answer = str(round(float(Answer),3)) form.FindElement('input').Update(Answer) Result = Answer # close the window elif button=='Quit' or button==None: break else: Result += button form.FindElement('input').Update(Result) |
Below is the full implementation :
Python3
# Import Module from PySimpleGUI import * # GUI Layout layout = [[Txt('' * 10)], [Text('', size = (15, 1), font = ('Helvetica', 18), text_color = 'black', key = 'input')], [Txt('' * 10)], [ReadFormButton('c'), ReadFormButton('«')], [ReadFormButton('7'), ReadFormButton('8'), ReadFormButton('9'), ReadFormButton('/')], [ReadFormButton('4'), ReadFormButton('5'), ReadFormButton('6'), ReadFormButton('*')], [ReadFormButton('1'), ReadFormButton('2'), ReadFormButton('3'), ReadFormButton('-')], [ReadFormButton('.'), ReadFormButton('0'), ReadFormButton('='), ReadFormButton('+')], ] # Set PySimpleGUI form = FlexForm('CALCULATOR', default_button_element_size = (5, 2), auto_size_buttons = False, grab_anywhere = False) form.Layout(layout) # Result Value Result = '' # Make Infinite Loop while True: # Button Values button, value = form.Read() # Check Press Button Values if button == 'c': Result = '' form.FindElement('input').Update(Result) elif button=='«': Result = Result[:-1] form.FindElement('input').Update(Result) elif len(Result) == 16 : pass # Results elif button == '=': Answer = eval(Result) Answer = str(round(float(Answer),3)) form.FindElement('input').Update(Answer) Result = Answer # close the window elif button == 'Quit' or button == None: break else: Result += button form.FindElement('input').Update(Result) |
Output:
