This page intends to give an overview of the different aspects of KDE development in particular for programming related issues. The KDE project welcomes anyone willing to help.
News and Mail Sources
The general direction of the KDE project is determined by those who do the work - there is no single high level plan for what KDE will look like in the future.
If you want to find out what is currently happening, then there are a number of sources you might like to consider:
- Mailing Lists
- Probably the best way to find out what's going on in KDE development. Archives are available here
- Receive notification of commits to the KDE source code repositories in areas that interest you.
- KDE Commit-Digest
- Weekly summary of commits to projects in the KDE source code repositories.
- The Dot
- The KDE news site.
If the application you are using crashes then the Dr Konqi utility will appear and guide you through the process of reporting the crash. Learn more by reading how to create useful crash reports.
Getting Started with Coding
Getting started at coding for KDE is a matter of finding something to fix, and fixing it. You may want to consult the module overview to help find what you are looking for; once you have fixed something, you will want to send in a patch. If you do that a few times, you may want to apply for a KDE Contributor account so you can improve things directly.
- Module overview
- Sending patches
- Applying for a KDE Contributor Account
- First steps with your new Contributor account
KDE is mostly written in C++. If you are not familiar with C++, you should do at least some work on it. There are a number of good books on C++ - an excellent source is Bruce Eckel's "Thinking in C++", which is available both as a free download and as a printed document. It isn't essential to understand everything before you start in KDE, but you do need to understand basic syntax and operations.
To become proficient with KDE coding, you should understand the Qt toolkit. If you are not familiar with Qt, you should work through the tutorials included with Qt Reference Documentation.
If you need a gentler introduction to Qt, or would just like an alternative view, then you may wish to look at the Foundations of Qt Development.
A range of information on KDE techniques is available in the tutorial section. Note that some of these tutorials still target KDE3, though they should be at least partly applicable.
You will also find useful information on KDE coding in the FAQs section. This information may also be somewhat dated for KDE4, however much of it is broadly applicable, even outside KDE.
You can also read KDE coding books.
Last, but by no means least, KDE comes with extensive class (Application Programmer Interface) documentation. This is available in the KDE API Reference Manuals section, which also contains a number of useful links on how to write or update the class documentation. You can also generate these on your own machine, or refer to a more up-to-date online version at API Reference.
A more detailed description of the steps above is available in our Programming Guide.
Context Help: Whatsthis
Context help is inseparable from the dialogs and widgets, as they are the target of the context help. In fact, in order to write context help, you have to touch programming or programming tools. Indeed, the context help is a property of widgets. In object oriented programming, a property can have different values, and behave differently depending on the value. In Qt/KDE programming, the name of the property is "whatsthis", and its value is the text the context help is going to display.
Fortunately, this task is usually not very difficult, as there are good tools to deal with user interface design, and better, you will use the knowledge acquired here later when dealing with user interface in general. Using the Qt framework (Qt is the base of KDE technology), it is possible to separate code and user interface. You have two basic cases here: the user interface is written with the general code of application (usually .cpp files) or in Qt Designer files (.ui files: it is a XML document). The second case is the best to start with, as it is simpler to work with. If you don't have Qt Designer installed, you can do so by installing the devel package of Qt from your distribution or the Qt Designer package (if your distribution has more fine grained packages).
Here you can find a detailed guide for writing whatsthis using Qt Designer and working directly with the source code: WhatsThis Tutorial, by Aaron J. Seigo.
Getting Involved in Bug Hunting and Application Quality
There is a large number of applications within KDE, and not all of them have a maintainer dedicated to managing bugs and generally helping out with all the issues associated with turning some working code into a polished application.
If you are interested in helping out with KDE, but don't know where to start, becoming a member of the KDE Quality Team might appeal to you - see the Quality Team website for more information. Note that you do not need any programming skills to become involved. In particular developers regularly publish so-called Junior Jobs to encourage new contributions.
Of course, you can become involved in bug hunting without being part of the KDE Quality Team - just create yourself an account on the KDE bug tracking system, and start searching / sorting through the bugs. Again, you don't have to have programming skills - it helps the programmers enormously just to have a procedure that allows a bug to be consistently reproduced.
The Bugsquad tries to keep track of bugs in KDE software and make sure that valid bugs are noticed by developers. You do not need any programming knowledge to be in the Bugsquad; in fact it is a great way to return something to the KDE community if you cannot program.
User interface is a very wide subject, and very subjective too, as something obvious to someone is absurd to others and vice versa. Therefore, don't assume, argue clearly, stating your logical steps. Your main tool discussing it are objective reasoning and good sense.
It is easy to perform a quick user interface analysis, but it is hard to convince people to change the interface. A good, convincing analysis can gain much if it incorporates information from the KDE guidelines, competing program and operational system analysis, general design principles found in many books, user testing or individual (anecdotal) feedback. It is a volunteer project, and even if everybody agree with you, someone has to implement it.
The KDE Usability Mailing List is very active and a good place for discussing your ideas, and their homepage is at http://techbase.kde.org/Projects/Usability. If you are already an usability expert, please check OpenUsability.org, a project that brings open source developers and usability experts together, and is collaborating closely with KDE.
Some projects for analysis of user interfaces may include: checking that shortcut keys are coherent across KDE applications, making sure that dialogs are directly relevant to the interaction that the user would expect, and finding users of KDE software to see how they perform common workflows.
Getting Answers to Your Questions
If your question concerns KDE development, your options are pretty much the same general user ones, with some modifications:
- Read the Developer FAQ. Many common developer questions have been answered in the KDE Developer FAQ
- Search/browse KDE websites. A lot of questions can also be answered from the KDE websites, and the documentation included on it. You can search all the KDE websites on the homepage. In addition, you can browse the KDE TechBase website. And if possible, help edit it for clarity, and use the talk page if something is unclear.
- Search mailing lists. A lot of questions have already been answered on the KDE mailing lists, particular the lists kde-devel, kde2-porting, kde-core-devel, kde-games-devel, kfm-devel and koffice-devel. You can search these lists at lists.kde.org. You should always search for your answer before asking questions on the mailing lists. When you ask a question on a mailing list you are emailing thousands of people -- please do this only if the answer is not available through a simple search.
- Search engines. Do not forget about your favorite search engine. One of the best search engines is Google. With Google you can also search the great bulk of Usenet news sites, which is also particularly helpful, especially for general programming and gcc-related questions.
- Read the source code. http://websvn.kde.org and https://projects.kde.org/ are available to help browse code. Read some commit logs and diffs for the code you might want to work with, It adds perspective.
- Ask on KDE mailing lists. If you still do not have an answer, try asking your question on one of the KDE mailing lists listed above.
- For questions relating to core development or third-party KDE development, unless you are particularly interested in Konqueror, KOffice, games or Java development, your main choice is kde-devel (subscribe).
- For questions relating to Konqueror development, your main choice is kfm-devel (subscribe)
- For questions relating to KOffice development, your main choice is koffice-devel (subscribe)
- For questions relating to games development, your main choice is kde-games-devel (subscribe)
- For questions relating to Qt development, please use the fine Qt mailing list.