Book Image

wxPython 2.8 Application Development Cookbook

By : Cody Precord
Book Image

wxPython 2.8 Application Development Cookbook

By: Cody Precord

Overview of this book

<p>In today’s world of desktop applications there is a great amount of incentive to be able to develop applications that can run in more than one environment. Currently there are a handful of options available for cross platform frameworks to develop desktop applications in Python. wxPython is one such cross- platform GUI toolkit for the Python programming language. It allows Python programmers to create programs with a complete, highly functional graphical user interface, simply and easily. wxPython code style has changed quite a bit over the years, and gotten much more Pythonic. The examples you will find in this book are right up to date and reflect this change in style.<br />This cookbook provides you with the latest recipes to quickly create robust, reliable, and reusable wxPython applications. These recipes will guide you from writing simple, basic wxPython scripts all the way through complex concepts, and also feature various design approaches and techniques in wxPython.<br /><br />The book starts off by covering a variety of topics from the most basic requirements of a wxPython application to some of the more in depth details of the inner workings of the framework laying the foundation for any wxPython application. It then explains event handling, basic and advanced user interface controls, designing and layout, creating dialogs, components and extending functionality, and so on. We conclude by learning how to build and manage applications for distribution.<br />For each of the recipes, there is an introductory example, then more advanced examples, and plenty of example code to develop and manage user-friendly applications. For more experienced developers, most recipes also include additional discussion of the solution, allowing you to further customize and enhance the component.</p>
Table of Contents (19 chapters)
wxPython 2.8 Application Development Cookbook
Credits
About the Author
About the Reviewers
www.PacktPub.com
Preface
Index

Understanding thread safety


Nearly all user interface toolkits are designed to run within a single thread of execution. Knowing how to interact with the GUI thread from other worker threads in a threaded application is an important task that needs to be performed with care in order to avoid seemingly unexplainable and random crashes in an application. This is as true in wxPython as any other typical GUI toolkit.

Maintaining thread safety in a wxPython application can be handled in a few different ways, but the use of events is most typical. The event queue monitored by the MainLoop provides a thread-safe way to pass data and actions from a background thread to be processed in the context of the GUI thread. This recipe shows how to use custom events and the Pos tEvent function to make updates to GUI objects that exist in the main GUI thread.

How to do it...

Since we will be using events to maintain thread safety in our sample application, we will first start by defining a custom event type...