Control Centre Modules

Introduction

The KDE Control Centre provides a standardised framework for customisation of the desktop environment, allowing the user to configure a wide variety of applications and services using a familiar interface. Control Centre modules provide flexibility for both the developer and user:

• Modules are stored under various categories within the Control Centre depending on their purpose. This makes configuration tools easier to find.
• They provide a standard user interface for applying, reverting and discarding changes to the configuration settings.
• Configuration can be performed outside the Control Centre through the use of the kcmshell tool.
• Modules are derived from a class which may be used in normal applications in order to provide a user interface which is consistent with the standard Control Centre experience.

The main advantage in writing Control Centre modules in Python lies in the language's strength as a rapid prototyping tool. The look and feel of modules can be changed easily, and new requirements accommodated quickly.

Requirements

A Control Centre module requires the following resources:

• A library to be loaded by the Control Centre, usually in the form of a .so file.
• A linking script (.la file) to ensure that the library is loaded correctly; this is automatically created when the conventional KDE build process is used.
• Information about the location of the library and linking script, the name of the module, the icon to use to represent it and other details; these reside in a .desktop file.

Python Control Centre modules also require their Python source code to be stored in a directory, either within the KDE installation directory structure ($KDEDIR/share/apps) or within the user's own KDE resources ($HOME/.kde/share/apps).

Examples

Three examples are included with the PyKDE components framework. Unfortunately, none of them really demonstrate true integration with the Control Centre environment since only the use of the Administrator Mode facility is used.

Default

Merely a prototype Control Centre module, this displays some information about some of the people involved with PyQt and PyKDE. This module is mainly used to test that the framework is installed and functioning at a basic level.

AppletConfig

Based on Jim Bublitz's panel applet installer, this module allows the same tasks to be performed from the familiar environment of the Control Centre. The user interface does not really fit it with its surroundings but, like the Default module, this is mainly a proof-of-concept example.

PyKDEComponent

More carefully integrated into the Control Centre environment than the previous example, this module provides the same functionality as the config.py installation tool. Once installed, the user may wish to continue installation of other components using this module.