KDE 4.0 released - Packages for Kubuntu available


A Vision Becomes Reality

Today, the KDE developers have as planned the first stable version of KDE 4.0 released. This release marks the start of the KDE 4 era. The desktop environment was given groundbreaking changes and improvements. More about this will be mentioned later in this article. The Kubuntu developers have made available packages for the releases 7.04 Gutsy Gibbons and 8.04 Hardy Heron.

After years of intensive development and with several month delay, the dream of the KDE community has become reality: KDE 4.0 has finally been released. The demands put on the entirely redesigned desktop are very high: All in all a revolution in the desktop area has been aimed for. Nevertheless, it would be wrong to expect too much from the newly released Version 4.0 due to the fact that several exciting features for the desktop environment have not been fully implemented yet. Therefore, it must be stressed that KDE 4.0 is not KDE 4 as the developer Stephan Binner aka beineri writes in his blog, but it is rather the beginning of a yearlong continuing set of release cycle interations.

Bild:KDE4-Plasma.png Bild:KDE4-Plasma2.pngBild:KDE4-Konqueror.png

Note: Das Original in deutsch ist hier zu finden ( The german original could be found here.)

For Everybody Who Cannot Wait: The Installation of KDE 4.0 under Gutsy Gibbon

There are already packages available for 7.10 Gutsy Gibbon and the current development version (8.04 Hardy Herron)

Since KDE 4.0 is installed into the directory /usr/lib/kde4, it is possible to install it next to the existing KDE3 installation. A test without installation can be achived with the KDE 4 Live CD.


  • Remove previous KDE 4 packages, they are not compatible (apt-get remove kdelibs5 kde4base-data kde4libs-data)
  • Install kde4-core, note that PPAs aren't authenticated so you will likely get a warning when installing
  • KDE 4 apps should appear in your KDE 3 K-menu or you can run a full session by selecting "KDE 4" from your login manager.
  • To avoid having to start a second X server for a full session install xserver-xephyr and run Xephyr :1 then and run /usr/lib/kde4/bin/startkde in the Xerphyr xterm.

A Summary of the Most Important Changes

The most obvious change are the new window decorations and the new icon set: Oxygen follows the guidelines of the freedesktop.org project. This allows a uniform, consistent and excellent look and feel of the new desktop environment Plasma. Plasma also provides a new panel and allows the start-up of a multitude of small applications called widgets.

In addition, there are numerous small and bigger changes on the desktop environment: There is a new dialogue for the opening of files. Dolphin has become a full file manager that leaves hardly any wishes open. The dialogue that allows the running of command has received numerous helpful features. Finally there is Kickoff that can replace the old KMenu. However, KMenu is still available too.

All these changes taken by themselves would only justify a new release 3.6.x. The most important changes of KDE 4.0 are invisible for the users. The KDE community made the decision to redesign a majority of the base code. The beginning is the task of porting the base code to release 4 of the Qt toolkit release by Trolltech. This allows KDE 4 applications to be used under numerous popular operating systems. In addition, the libraries - known as kdelibs - have been streamlined.

Finally, several base technologies that will simplify the development of KDE 4 applications have been integrated. Some of those technologies, as Solid and Phonon will already be contained by the release 4.0. Others, as Decibel and Akonadi will not be available until later releases. These technologies are hidden for the users. Their full featureset will not be seen until they are integrated into the applications running under KDE 4. This will step by step release the full potential of KDE 4.


Platform Independence

During the development of KDE 4, there has been a big emphasis on platform independence. All KDE 4 application shall be able to run on all popular operating systems (Windows, Mac OS X, etc.) and are currently ported for this purpose. This is possible, among other things, due to the high grade of flexibility of Qt. This is shown by the example of Amarok 2. After only 2 days, it was possible to compile and start Amarok 2 on Windows. It is currently not planned to port Plasma, but the developers made it known that they would not be surprised if "some nut" would port Plasma onto Windows. During a proof of concept, it was shown that Plasma could be compiled and started on a Neo 1973 Smartphone.

Qt 4

The Qt-Toolkit by Trolltech is the foundation of KDE. With the new generation Qt4 there have been several positive changes. One example is the distribution of the library into finer granuality which alows to develop smaller and more memory efficient programs. This also achieved that the new KDE release uses far less memory than its predecessors. An important part of Qt 4 is the new paint engine Arthur. It is able to use OpenGL far more effective than it is used in Qt 3. In addition, a comprehensive functionality for SVG was added.

KDE 4.0 is build on top of Qt 4.3. In addition, Qt 4.4 (final release 1 is scheduled for the first quarter of 2008) will be used, which is already the foundation of Amarok 2.


Phonon is contrary to some fears not a new sound system in the fashion of GStreamer or similar, but rather as a layer between the sound system and the audio applications. Phonon has not the the functionality to allow komplex transformations of multimedia data, but serves as a simple input and output layer for multimedia data to the backend (as i.e. GStreamer, Xine, etc.). Important advantages for this are platform independence and flexibility. In this way, KDE 4 applications do not need to have any knowledge about the underlying multimedia architecture, but only need to intereract with Phono's application interface.

It is not necessary to install an additional sound system on every platform in order to allow KDE 4 applications to work. Applications can simply access the functionality through the backend of the underlying platform. Should the user decide to change the sound system during the runtime of an application, it is only necessary for Photon to exchange the backend without any interference of the running KDE 4 applications. This means that problems as the one with a sleeping arts daemon will be issues of the pasttime. aRts has been used in KDE 3 and before to play and record sounds. The buffers filled up with time and after the wake-up multiple sounds would be played in an overlaying fashion. Another additional feature will be the possibility to have the sound output by several applications be activitated dependent on each other. As an example, the sounds of all other applications could be temporarily muted while the user is listening to a webstream.

Trolltech has already announced that Phonon will be integrated into the next Qt releases.




Solid is similar to Phonon a framework that allows KDE 4 application the access or usage of hardware. In this context, there is a network manager backend that allows applications to know at any time the status of the network connections. If a WLAN hotspot is left, this allows any applications that depend on an Internet connection to switch into an offline mode. Due to the fact that Solid is quite new, this technology must first be implemented into the applications. Further backends currently available under Solid are backends for the battery management and bluetooth.


Strigi is the small and very fast index based desktop search engine that is already known from Gutsy Gibbon. In contrast to the KDE 3 version, Strigi is now far more mature and in conjunction with the semantic functions provided by Nepomuk a very powerful search tool. Similar as to the usage of beagle under Gnome, it is now possible to index files in order to allow faster searches. In addition, Strigi works very resource efficient and therefore does not put such a high load on the system as other desktop search engines do.


Nepomuk is not a pure KDE project, but a big research and development project which is supported by numerous companies, researchers and developers. Their goal is the vision to revolutionise information management with the aid of information technology by creating a semantic desktop.

The implementation of Nepomuk in KDE 4 allows to tag files with keywords (so called tags) or to add comments. In turn these tags can be used for searching in a similar way as this is already possible on blogs or multimedia sites such as Youtube. Since the tags remain associated to the files even if they are renamed, it is very easy to search for files that have been accidentally renamed. The tag system also allows files to be sorted according to contents. As an example, a tag with the description "dog" could be created which could be assigned to all video files or image files that contain a dog. Nepomuk is already integrated into Dolphin.

The Most Obvious Changes to KDE 3.5.x


Certainly, the most obvious change in KDE 4 is Plasma, the new desktop. It is fully based on the concept of widgets. Behind the widgets are small applications that smong other things show the status of batteries, rss feeds, or show a clock on the desktop. These widgets can be freely placed either on the desktop, or on the taskbar. Previously two different widgets were necessary for this.

Due to the fact that the widget recognises where it is placed, it automatically adjusts its size and behaviour. As an example, a widget which would show lots of information and maybe even a graphic on the desktop, would show fewer but important information inside the taskbar. Since these application are fully based on SVG technology, it is possible to freely scale and rotate them.

The taskbar itself is now also a widget which allows the integration of additional widget inside itself. This means the task panel, system tray and K-button are also widgets that can placed and exchanged in the way the user wishes. This allows more flexibility in creating the completely individual desktop.

Since Plasma was one of the last projects that have been tackled during the KDE 4 development, at this time, only a small set of widgets are available. The panel can also configured in limited ways at this time.



Kcontrol has been responsible for the configuration of KDE for a long time. Due to all its options and its structure, it was too complex for the taste of many users. Therefore, Kubuntu introduced Systemsettings, which in turn has found its way into KDE 4 and replaces KControl. The simplicity of its concept makes it easy for new users to configure the environment according to their wishes. However, it still allows the advanced users to configure the complex options of configuration of the desktop.


The file manager Dolphin was completely redesigned for KDE 4. In addition to the features of Nepomuk, Dolphin offers a different model that allows files to be sorted according different attributes in order to manage them (i.e. alphabetically, user permissions, etc.). The tree structure that is used by many users in the KDE 3 Version of Dolphin is still available. In addition, Dolphin now allows a column display similar to the one that is known from OS X. Dolphins main focus is the management of files, which can easily be achieved with its comprehensive functionality. However, it will also in future be possible to use Konqueror for managing files.


The new face of KDE has the name Oxygen. It not only contains the new look & feel for the windows but also a comprehensive set of icons which have been adjusted according to the naming conventions of freedesktop.org. The named aim has been to design the icons in a uniform and consistent way. The technology used is the vector format SVG. This allows full scalability and dynamical adjustments to colour. The design is completed with a KDE style and matching cursor theme and new sounds.


Since the introduction of AIGLX it is possible for XServer to display graphical effects similar to Mac OS X. In order to create such effects it is necessary to have a composite manager as i.e. Compiz-Fusion. Compositing does not only look very nice, but can also enhance the usability. Therefore, KWin has been enhanced with its own composite manager, which can be activated according to need and hardware availability. The manager allows to switch on and off the different effects that are available.


As a substituion of the previous menu item "Run Command", which was able to execute commands, KRunner has now been integrated. KRunner has been extended and integrates now Katapult, Strigi, and the command line interface as one. After the input of a term, all sources will be searched simultaneously and depending on the result, different options will be offered for selection.


Prospects of KDE 4.x

According to the paradigm of the open source community "release often, release early", some of the core technologies for the KDE desktop will not be available in the first release of KDE 4. In particular, this can be said about Akonadi, which is the individual private information management for KDE. Akonadi shall give a central repository for all kinds of groupware data, which in turn will be made available for all applications. The uniformity and access control for the data will prevent that applications can interfere with each other or the need of data conversions.

It can be expected that the already existing technologies will be integrated into the applications and step by step all KDE applications will be ported to Qt4 and KDE 4. This also relates to some important applications like Amarok and KOffice. The new version 2.0 of KOffice could not be released in time for KDE 4.0. However, there is great hope for it. In particular, it is an aim to make KOffice2 the default office suite for Kubuntu.

High expectation also exist for the audio player Amarok 2. There will be a completely redesigned user interface which will be built around the context browser. It will have integrations, among others, for the popular online services as well as context information from wikipedia and a built-in of the Magnatune shops.