Book Image

Tkinter GUI Application Development Blueprints

By : Bhaskar Chaudhary
Book Image

Tkinter GUI Application Development Blueprints

By: Bhaskar Chaudhary

Overview of this book

Tkinter is the built-in GUI package that comes with standard Python distributions. It is a cross-platform package, which means you build once and deploy everywhere. It is simple to use and intuitive in nature, making it suitable for programmers and non-programmers alike. This book will help you master the art of GUI programming. It delivers the bigger picture of GUI programming by building real-world, productive, and fun applications such as a text editor, drum machine, game of chess, media player, drawing application, chat application, screen saver, port scanner, and many more. In every project, you will build on the skills acquired in the previous project and gain more expertise. You will learn to write multithreaded programs, network programs, database driven programs and more. You will also get to know the modern best practices involved in writing GUI apps. With its rich source of sample code, you can build upon the knowledge gained with this book and use it in your own projects in the discipline of your choice.
Table of Contents (15 chapters)
Tkinter GUI Application Development Blueprints
About the Author
About the Reviewers

Dealing with mouse events

When we draw in a paint program, we use a mouse as the primary input device. There are primarily two kinds of mouse events that cause changes on the drawing canvas and are therefore of main interest:

  • Click and release

  • Click, drag, and release

There is also a third event in which we have limited interest—the mouse motion with no buttons clicked. Our interest is limited there since an unclicked motion normally does not cause any changes on the canvas.

We ignore right-click and wheel-scroll as we will not be using them in our program.

In both the preceding cases, we need to know where the mouse was first clicked and where it was released. For click and release this could be the same location. For click, drag, and release this will normally be different locations.

Accordingly, we define four attributes to keep track of the coordinates for these two locations (see code

    start_x, start_y = 0, 0
    end_x, end_y = 0, 0

Our immediate goal then is to bind our mouse...