Development/Tutorials

Tutorials are the fastest way of finding out what KDE will do for you, and how to do it. Here is a list of currently available tutorials for KDE4. Material for KDE3 and KDE2 is available on the bottom of this page.

Introduction To KDE 4 Programming

Are you interested in writing applications with KDE 4? This tutorial series is aimed at those completely new to KDE programming.

Hello World: A preliminary introduction to the very basics of KDE4 programming

Creating the Main Window: This tutorial shows you the magic of an application's most important thing: The main window.

Using KActions: How to add actions to the menus and toolbars.

Saving and Loading: Introduces the KIO library while adding loading and saving support to our application.

Command line arguments: Adds the ability to specify which file to open from the command line to our text editor.

Basics

Porting Your Application: Help Porting Applications from Qt3/KDE3 to Qt4/KDE4

Introduction to CMake: How to use the CMake build system used by KDE4.

Common Programming Mistakes: Various common mistakes made while developing Qt and KDE applications and how to avoid them.

Using Qt Designer to build user interfaces: How to create UI files with designer, and how to integrate them into a KDE program.

Creating Libraries to share code: How to add the library to the buildsystem and how to prepare the source code.

Session Management: Make your application aware of X sessions

Testing And Debugging

Debugging your application: Tips, tools and techniques to apply when debugging your KDE application

Writing Unittests for Qt4 and KDE4 with QTestLib (Original link): Tutorial by Brad Hards that describes how to write unit tests using the QTestLib framework. It is presented as an example based tutorial, and is still under development.

Semi-automatic ways to detect code errors: Techniques you can use to detect errors in KDE code

Managing Configuration Data With KConfig

Introduction To KConfig: An overview of the KConfig classes and how to use them in your application code

Using KConfig XT: Tutorial on how to efficiently use the KConfig XT framework.

Updating KConfig Files: Tutorial on how to write an update script to keep changes in your application's config file format in sync with the user's already existing config file

Services: Applications and Plugins

Introduction to the Services Framework: An overview of the services framework in KDE and what it provides the application developer. Covers the system configuration cache (SyCoCa), the source data files and what the indexed information can be used for.

Finding Services Using Trader Queries: How to find services, such as plugins or mimetypes, that are indexed in the SyCoCa using Trader Query Syntax

Creating and Loading Plugins Using KService: Learn how to define custom plugin types, find installed plugins (including 3rd party plugins) and load them in an easy and portable fashion using KService.

Localization

Documentation

API Documentation: This tutorial explains how to document your APIs properly.

Man Pages: Writing and Generating Reference Manual Pages.

Application Automation and Scripting

D-Bus

Introduction to D-Bus: A straight-forward introduction to the core concepts in D-Bus from an application developer's perspective, this tutorial covers what D-Bus is and how it can be used by applications.
Accessing D-Bus Interfaces: A step-by-step guide to calling D-Bus methods and connecting to D-Bus signals using QtDBus.
Intermediate D-Bus: Tips to make use of QtDBus when faced with problematic real-world interfaces.
Creating D-Bus Interfaces: Learn how to expose functionality in your application by creating and using custom D-Bus interfaces. Covers generating the XML descriptions, instantiating interfaces at run time and setting up the build system with CMake.
D-Bus Autostart Services: Turn your application into a D-Bus autostart service with this tutorial. This D-Bus feature, also known as "D-Bus service activation", will ensure that even when your application isn't running that D-Bus calls made to it will work by relying on the D-Bus daemon itself to start your app if and when needed.
Porting from DCOP to D-Bus: Port your applications from DCOP to D-Bus with this handy guide.

Konqueror

Creating Konqueror Service Menus: This tutorial shows you how to create mimetype-specific actions in Konqueror's context menu (aka "servicemenus").

Kross

Introduction to Kross: An introduction to the Kross Scripting Framework.

Hello World: A first application with working kross code.

Calling Functions in Kross: Simple demonstration of calling scripting functions

Connecting Signals and Slots in Kross: Simple demonstration of connecting object signals with script slots

Scripts as Plugins with Kross: This tutorial provides a step-by-step introduction how to integrate scripts as plugins into a KDE application.

Placing script actions in your application menus: Simple demonstration on how to extend you application menus to execute script files.

Calligra Plugin Tutorials

Calligra Overview

This document shows an overview of the different Calligra plugin types and tells you what each of their purpose and strengths are. If you are new with Calligra plugins, this is the place to start.

Calligra Plugin Creation

This gives a technical overview of what it means to write a Calligra plugin.

Creating Calligra Flake Plugins

This tutorial shows you how you can build a plugin for Calligra applications to allow you embed content in ODF documents using Flake.

Calligra Words Scripting

This tutorial shows how to script Calligra Words with Python, or JavaScript using Kross.

Calligra Sheets Scripting

This tutorial shows how to script Calligra Sheets with Python, or JavaScript using Kross.

SuperKaramba

SuperKaramba Tutorial: This tutorial provides an overview of SuperKaramba, theme files and scripting with Python, Ruby and JavaScript.

Plugins and KParts

Writing kontact plugins: Kontact plugins are KParts. This tutorial describes how you can write one.

Using KParts: Learn how to load a KPart into an application window.

Writing Qt Designer Plugins: Add your widgets to Qt Designer and thus make them usable in UI files.

Search and Metadata

Strigi

Writing file analyzers: File analyzers extract data from files to display in the file dialogs and file managers. The data gathered this way is also used to search for files. KDE4 allows the use of multiple analyzers per file type. This tutorial describes how you can write new analyzers.

Nepomuk

Nepomuk Quickstart: How to use Nepomuk resources in a quick and painless way without much fuss.

RDF and Ontologies in Nepomuk: An introduction to RDF and the usage of ontologies in Nepomuk.

Data Layout in Nepomuk: An overview of which and how data is stored in Nepomuk.

Handling Resources with Nepomuk: Nepomuk is the KDE library which provides easy access to metadata in the Nepomuk system. Learn how to make your application create and read metadata using the Nepomuk system.

Using the Nepomuk Resource Generator: Nepomuk includes a resource generator which creates convenience classes for handling metadata.

Advanced Queries: The real power of Nepomuk can only be exposed when performing fancy queries on the data repository. This tutorial provides an introduction to semantic and full text queries in Nepomuk.

The Nepomuk Server and the Architecture of the Nepomuk subsystem: The Nepomuk Server hosts the main Nepomuk data repository and can be accessed directly via a Soprano API.

Nepomuk Services

The Nepomuk Server manages a set of Nepomuk services.

Storage Service The probably most important service hosts the Nepomuk data repository using Soprano.
Ontology Loader Makes sure installed ontologies such as RDF, RDFS, NRL, or Xesam are loaded into the storage repository.
File Watch Service Monitors the file system for changes and updates the file resource paths and URIs in Nepomuk.
Strigi Service Controls Strigi, the file indexing tool which extracts metadata from files and stores it into the storage repository.
Query Service Provides persistant query folders.

Nepomuk Tips and Tricks: A set of tips and tricks for development with Nepomuk and Soprano. This is a must-read if you intend to use Nepomuk in your application or hack on it directly.

Hardware Awareness (Solid)

Introduction to Solid: An introduction to using the Solid hardware discovery and interaction system in KDE applications.

Accessing Network Information: How to use the Solid system to get information about the network

Privileged Applications (PolicyKit)

Introduction to PolicyKit: A straight-forward introduction to what PolicyKit is, and how it can be useful for your next application requiring super-user privileges or user authentication
Using the caller-helper model to perform actions as root: This tutorial will teach you how to get your application to perform some actions as root in a completely safe and easy manner, if the user is authorized to, by using PolicyKit and the caller-helper technique
Getting root privileges in KCM Modules: This tutorial will teach you how to create KCModules able to save settings as root

Multimedia (Phonon)

Phonon: How to start with the multimedia API

How to compile and use Phonon and its GStreamer backend on Linux using Qt 4.3.x

This article gives you a quick brief of how you can use checkout, compile Phonon and its GStreamer backend on GNU/Linux with just Qt 4.3.x. Towards the end, the article also describes how a developer can make use of Phonon to create simple audio and video players. You can read the article here. You can download the editable OpenDocumentText file from here.

Plasma

See Development/Tutorials/Plasma for Plasma tutorials.

Communication (Decibel)

Getting started with Decibel: This tutorial describes how to set up Decibel.

Handling TextChannels: This tutorial introduces the basics of handling incoming TextChannels by guiding you through building a simple text chat application.

Personal Information Management (Akonadi)

Using Akonadi in Applications: Displaying and modifying data provided by Akonadi

Developing Akonadi Resources: Akonadi Resources are agent programs which transport PIM data between Akonadi and a backend (files, servers, etc)

Using custom data types with Akonadi: Akonadi can handle arbitrary data as item payloads through the use of a plugin based serialization framework

Kate / Kwrite

Getting started with KTextEditor plugins: Creating your first KTextEditor plugin

Developing a plugin with configuration dialog: Adding a configuration dialog to the Time & Date example

A small Editor: Create a small application using KTextEditor

Printing

Hello World: Introduction to the KDE printing system

Print Dialog: Using the KDE print dialog

kioslaves

Get Hot New Stuff

New introduction to Get Hot New Stuff 2: A short tutorial about how to use KHotNewStuff2 in your application.

old links for KNS1 content:

Introduction to Get Hot New Stuff: An introduction to the developer-friendly network update system that allows KDE applications to fetch new application data at runtime in a user friendly manner.

KNewStuff Secure (Original Link): Tutorial showing how to share resources in a secured way (KDE 3.4 and later). By András Mantia <[email protected]>.

Goya

Introduction to Goya usage: An introduction for the Goya subsystem usage, which allows you to easily add widgets to your itemviews and connect their signals to your code, as they were real widgets.

Introduction to Goya usage (part 2): The second part of the tutorial, with a slightly more complex example than the first part.

Other programming languages

Python

An Introduction to PyQt: Starting off

PyQt by Example: Another introduction to PyQt

PyKDE WebKit Tutorial: A simple web browser application in PyKDE

101 Introduction to signals and slots: A simple introduction to Qt's signal and slot architecture.

PyKDE DBus Tutorial: An introduction to DBus communication using PyKDE

Ruby

KDE Ruby Korundum tutorial: A ruby version of Antonio Larrosa Jiménez's KDE tutorial by Richard Dale. See the Ruby Developers Corner for Qt tutorials and other info.

Qt4 Ruby Tutorial: Trolltech's fabulous introductory tutorial to Qt, translated to Ruby.

Creating a Plasma Widget in Ruby: Tutorial that shows how to create your first Plasma Applet using the Ruby language.

Developing Qt4 Applications using Qt Designer and Ruby on Kubuntu: Tutorial that shows how to design a simple User Interface in Qt Designer and then use the resulting widget in a Qt Ruby application we build from scratch.

Shell

Shell Scripting with KDE dialogs (Original Link): Tutorial by Brad Hards that describes how to use KDE dialogs in shell scripts with kdialog. It is presented as an example based tutorial.

Graphics Programming

QPainter Perfomance: Hints on avoiding common mistakes leading to poor performance when using QPainter

Using the KDE Games Libraries

KStandardGameAction: Using libkdegames to make your game fit the kdegames standard
Highscores: Implementing a simple highscore table into your game
Theme Selector: Using the libkdegames theme selection dialog
Palapeli Patterns: Creating a pattern for Palapeli

Using the KDE PIM Libraries

iCalendar functionality: Using kcal to manage iCalendar files

KDE2 and KDE3 Materials

KDE3 Tutorials: These tutorials cover topics related to KDE3.

KDE2 Tutorials: These tutorials cover topics related to KDE2.