In this chapter, we delved into the topic of QGIS plugin programming. We created two separate plugins, a simple one to get started with, and a more complex and useful plugin that displays information about a clicked-on feature's geometry. We also looked at the QGIS plugin architecture, the plugin development process, and some of the possibilities and limitations of QGIS plugins. Along the way, we learned about the tools needed to develop QGIS plugins, discovered that plugins are simply Python packages with certain special files in them, and saw how the PyQt command-line tools can be used to compile user-interface templates and resource description files into Python modules so that they can be used within a plugin.

We also looked at how your plugin is integrated into the QGIS user interface using icons and menu items, how to run your plugin, and what happens when your plugin crashes. We also looked briefly at the Plugin Builder, and how it can be useful.

Next, we looked at how to use...