Book Image

Python GUI Programming Cookbook - Third Edition

By : Burkhard Meier
Book Image

Python GUI Programming Cookbook - Third Edition

By: Burkhard Meier

Overview of this book

Python is a multi-domain, interpreted programming language that is easy to learn and implement. With its wide support for frameworks to develop GUIs, you can build interactive and beautiful GUI-based applications easily using Python. This third edition of Python GUI Programming Cookbook follows a task-based approach to help you create effective GUIs with the smallest amount of code. Every recipe in this book builds upon the last to create an entire, real-life GUI application. These recipes also help you solve problems that you might encounter while developing GUIs. This book mainly focuses on using Python’s built-in tkinter GUI framework. You'll learn how to create GUIs in Python using simple programming styles and object-oriented programming (OOP). As you add more widgets and expand your GUI, you will learn how to connect to networks, databases, and graphical libraries that greatly enhance the functionality of your GUI. You’ll also learn how to use threading to ensure that your GUI doesn't become unresponsive. Toward the end, you’ll learn about the versatile PyQt GUI framework, which comes along with its own visual editor that allows you to design GUIs using drag and drop features. By the end of the book, you’ll be an expert in designing Python GUIs and be able to develop a variety of GUI applications with ease.
Table of Contents (13 chapters)

Writing callback functions

At first, callback functions can seem to be a little bit intimidating. You call the function, passing it some arguments, and then the function tells you that it is really very busy and it will call you back!

You wonder: will this function ever call me back? And how long do I have to wait? In Python, even callback functions are easy and, yes, they usually do call you back. They just have to complete their assigned task first (hey, it was you who coded them in the first place…).

Let's learn a little bit more about what happens when we code callbacks into our GUI. Our GUI is event-driven. After it has been created and displayed onscreen, it typically sits there waiting for an event to happen. It is basically waiting for an event to be sent to it. We can send an event to our GUI by clicking one of its buttons. This creates an event and, in a...