Real World Instrumentation with Python

Graphical User Interfaces

All modern general-purpose operating systems incorporate some type of graphical user interface (GUI) into their design. Only those operating systems intended for deeply embedded applications don’t come with some kind of GUI, since they don’t need one anyway (they usually don’t have any kind of user interface display, actually).

The GUI is a layer of functionality on top of the core operating system, and in some cases it may even be optional. In a Unix or Linux system, the GUI is started after the operating system loads as a discrete step in the boot sequence, and a Linux system will run just fine without the GUI. In other cases, such as with Windows, the GUI is tightly integrated into the OS, and while still technically a layer of functionality, it is not designed to be easily disabled.

In this section we’ll see how to use a GUI with Python. I won’t go into detailed code examples, mainly because anything beyond a simple “Hello World” GUI can get rather involved. What we will do is look at where the whole GUI concept originated, and why you might want to use one, rather than simple command-line or ANSI solutions like the ones we’re already seen in this chapter. We will wrap up with a look at some simple data display GUIs to give you a sense of what is involved in creating a GUI.

Some GUI Background and Concepts

Before undertaking a quick survey of a couple of GUI toolkits for Python, I’d like to take a look at the history of the GUI as we know it today. Many ...