ISV/Developer Information

Tools

You can use the Subversion version control system to access the KDE source repository.
There is a list of tools available, that can be used for developing KDE applications. These include low-level debuggers, as well as the KDevelop *Integrated Development Environment (IDE), and various design programs.
You may also want to read the Compilation FAQ.
Several volumes of development documentation will help you getting started with your development.

Libraries and Interfaces

DCOP and D-Bus

DCOP is the message bus built into KDE 3, that is used for inter-process communication (IPC) between different KDE applications. DCOP can be used in order to remotely control KDE applications from your own application or to provide scriptable interfaces for your own application.

Creating a DCOP Interface
This tutorial shows you how to create a DCOP interface to a KDE application.

KDE Automation writeup
Document by Olaf Zanger showing an overview of the scripting capabilities in KDE 2.x. Includes usage of "dcop", "kdcop", scripting languages, xmlrpc, and a FAQ.

Connect KDE applications using DCOP
IBM DeveloperWorks tutorial, shows how to use kdcop and dcop with several examples such as instantly messaging a contact in kopete when he comes online, and also how to create a simple DCOP-aware application.

D-Bus will be the message bus used in KDE 4.

D-Bus Tutorials
This tutorials show what D-Bus is and how to use it.
See also: D-Bus tutorial at freedesktop.org.

KIO-Slaves

KDE is network transparent. This means that each application can access files via many network protocols just as if they were stored locally. There exist access modules (KIO-Slaves) for Samba (Windows Shares), HTTP, FTP and many other protocols.

Using IOSlaves
IOSlaves are the subprocesses KDE uses to fetch remote files without blocking the user interface. This document discusses how they work and how to use them. (Somewhat dated, but might still be useful).

Portland: xdg-utils and DAPI

KDE actively supports The Portland Project aiming at making cross-desktop application development easier. For more information on this fairly young project, please refer to The Portland Project's website hosted on Freedesktop.org.