Now that we've seen how plugins are structured and used, let's create a very simple "Hello World" style plugin to see what's involved in making one. While there are various tools such as the Plugin Builder plugin, which will create the various files for you, we're going to eschew them in favor of creating our plugin manually. This will make the process clearer and avoid the situation where your code just magically works without knowing why or how.

Go to the ~/.qgis2/python/plugins directory and create a subdirectory named testPlugin. In this directory, create a file named metadata.txt and enter the following values into it:

[general]
name=Test Plugin
[email protected]
author=My Name Here
qgisMinimumVersion=2.0
description=Simple test plugin.
about=A very simple test plugin.
version=version 0.1

This is the minimum metadata you need to enter for a plugin. Obviously, you can change these values if you want. Now, create a package initialization file, __init__.py, and...