Programming Python, 3rd Edition

ShellGui: GUIs for Command-Line Tools

To better show how things like the GuiMixin class can be of practical use, we need a more realistic application. Here’s one: in Chapter 6, we saw simple scripts for packing and unpacking text files. The packapp.py script we met there, you’ll recall, concatenates multiple text files into a single file, and unpackapp.py extracts the original files from the combined file.

We ran these scripts in that chapter with manually typed command lines that weren’t the most complex ever devised, but were complicated enough to be easily forgotten. Instead of requiring users of such tools to type cryptic commands at a shell, why not also provide an easy-to-use Tkinter GUI interface for running such programs? While we’re at it, why not generalize the whole notion of running command-line tools from a GUI, to make it easy to support future tools too?

A Generic Shell-Tools Display

Examples 11-5 through 11-8 comprise one concrete implementation of these artificially rhetorical musings. Because I wanted this to be a general-purpose tool that could run any command-line program, its design is factored into modules that become more application-specific as we go lower in the software hierarchy. At the top, things are about as generic as they can be, as shown in Example 11-5.

Example 11-5. PP3E\Gui\ShellGui\shellgui.py.py

#!/usr/local/bin/python ################################################################################ # tools launcher; uses guimaker templates, guimixin ...