Developing GUI applications in Python with PySimpleGUI

Python is a powerful and versatile programming language that can be used in a variety of applications. One common use case for Python is in developing graphical user interfaces (GUIs) for desktop applications. One popular library for creating GUIs in Python is PySimpleGUI.

In this tutorial, we will walk through the basics of developing a GUI application with PySimpleGUI. We will cover the following topics:

1. Installing PySimpleGUI
2. Creating a simple GUI window
3. Adding widgets to the GUI window
4. Handling user input
5. Running the GUI application

Let’s get started!

1. Installing PySimpleGUI

The first step is to install PySimpleGUI. You can easily do this using pip by running the following command in your terminal or command prompt:

pip install PySimpleGUI

This will install PySimpleGUI and any necessary dependencies.

1. Creating a simple GUI window

To create a simple GUI window with PySimpleGUI, you need to import the library and create a window object. Here’s an example of how to do this:

import PySimpleGUI as sg

layout = [
    [sg.Text('Hello from PySimpleGUI!')],
    [sg.Button('Ok')]
]

window = sg.Window('My First GUI App', layout)

In this code snippet, we import PySimpleGUI as sg and create a layout that consists of a Text widget displaying a message and a Button widget labeled ‘Ok’. We then create a window with the title ‘My First GUI App’ and the specified layout.

1. Adding widgets to the GUI window

PySimpleGUI provides a wide range of widgets that you can use to create interactive GUI elements. Some common widgets include Text, InputText, Button, Checkbox, Listbox, and Combo. You can add these widgets to your GUI window by including them in the layout list.

Here’s an example of a more complex layout that includes multiple widgets:

layout = [
    [sg.Text('Enter your name:'), sg.InputText()],
    [sg.Text('Select your favorite color:'), sg.Combo(['Red', 'Green', 'Blue'])],
    [sg.Button('Submit')]
]

window = sg.Window('My Second GUI App', layout)

In this layout, we have added an InputText widget for the user to enter their name, a Combo widget with a drop-down list of color options, and a Button widget labeled ‘Submit’.

1. Handling user input

Once you have added widgets to your GUI window, you can handle user input by creating an event loop that listens for user interactions and responds accordingly. PySimpleGUI provides an easy way to do this using a for loop and the read method of the window object.

Here’s an example of how to handle a button click event:

while True:
    event, values = window.read()

    if event == sg.WIN_CLOSED or event == 'Submit':
        break
    else:
        print(f'You clicked the {event} button')

In this code snippet, we create a while loop that listens for events and values from the window. If the event is equal to the WIN_CLOSED event or the ‘Submit’ button event, we break out of the loop. Otherwise, we print a message indicating which button was clicked.

1. Running the GUI application

Finally, to run your GUI application, you simply need to call the window.close method to close the window and clean up any resources used by the GUI.

Here’s the complete code for a simple GUI application with PySimpleGUI:

import PySimpleGUI as sg

layout = [
    [sg.Text('Enter your name:'), sg.InputText()],
    [sg.Text('Select your favorite color:'), sg.Combo(['Red', 'Green', 'Blue'])],
    [sg.Button('Submit')]
]

window = sg.Window('My First GUI App', layout)

while True:
    event, values = window.read()

    if event == sg.WIN_CLOSED or event == 'Submit':
        break
    else:
        print(f'You clicked the {event} button')

window.close()

When you run this code, you should see a GUI window with input fields for name and color selection, as well as a submit button. You can interact with the GUI by entering your name, selecting a color, and clicking the submit button.

In conclusion, PySimpleGUI is a user-friendly and versatile library for developing GUI applications in Python. With a simple and intuitive API, you can quickly create interactive and visually appealing desktop applications. I hope this tutorial has helped you get started with PySimpleGUI and that you now feel more confident in developing GUI applications with Python. Happy coding!