2002.05_Kde 3-We Check Out the Differences in the Latest Version.pdf

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SMALL CAUSE,

LARGE EFFECT

version number changes, this usually

suggests drastic modifications to the

software. KDE 3.0 however proves that this doesn’t

have to mean that users will hardly recognise their

programs any more. The current version change is

more like a leisurely step in comparison to the leap

from KDE 1.x to 2.x. The change in optics will only

immediately catch the eye of the most observant

users and apart from this nothing particularly incisive

has changed to the technology under the hood. So

why the new major version number ?

KDE 3.0, in its release

candidate state, was

one the stars of the

Linux World Expo in

New York. Patricia

Young takes a closer

look at the pre-

release versions

From right to left and back again

The intention is that KDE’s versioning remains in

synch with that of the underlying GUI Library . With

KDE 3.0, this essentially concerns the porting of KDE

2.2.x to Qt 3.0.x. Now this in itself does not sound

particularly mind-blowing, however it has quite

interesting consequences: since the support for non-

Latin alphabets, as well as bi-directional

representation has improved in Qt 3, KDE also

profits from this.

A KDE 2 application like the KDE control centre on

a SuSE 7.2 installation (not intended for the Israeli

market) with an imported Hebrew KDE

Internationalising Package only outputs question

marks (Figure 1), whereas the language conversion

works perfectly with KDE 3. Not only can Hebrew

program labels be surveyed (see Figure 2) without the

additional installation of fonts, but also the

arrangement of the menus and buttons automatically

adapt to the right-to-left reading direction giving a

mirror image of what European eyes are used to.

The KDE control panel (bar) however was not

obliging (at least in the latest CVS version before

Major version number This is generally defined as the number before the first

decimal point of a version specification – in contrast to the “minor version

numbers”, which follow thereafter. This main version number normally only changes

with large re-organisations and improvements in functionality. If another decimal

point follows the minor version number, the number following this usually defines a

“maintenance release”, which in theory is only concerned with bug fixes. However,

not all projects adhere to this unwritten rule.

GUI Library A collection of source code for elements and graphic user surfaces

(buttons, windows, menu bars, dialogs etc.), which programmers have prefabricated

and made available as classes. The most common under Linux are GTK+ and Qt.

Figure 1: The transfer to Arab or

Hebrew is not as simple with KDE 2.x

Bi-directional representation (or “Bidi” for short). There are times within texts

written from right to left (such as Hebrew and Arabic), that terms may arise in

languages written from left to right (e.g. English or Russian). The

writing/representation direction must therefore change for a short while. This is a

very demanding and sophisticated function of GUI programming.

Issue 20 • 2002

LINUX MAGAZINE

KDE 3.0

W hen the digit before the decimal point of a

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Figure 2: With

KDE 3 however

it’s a matter of

course

going to press), so that the arrows in the mirrored

start menu were pointing in the wrong direction.

The fact that KDE 3 so miraculously gets the

correct font is due to the reworked QFont class in Qt

3. The consequence of this is that the program no

longer stubbornly outputs the same old backup

symbols (which cover all characters) when it can’t

find the correct font. Instead of this, it picks the

suitable glyphs from the available system fonts and

even mixes these together if necessary. Letting the

old KDE code use the new QFont API was thereby

one of the most difficult functions of the porting.

Figure 3: Overloaded main windows can be broken up

the code of several KDE programs. By the way, it is

pretty self-evident that the KDE editor Kate is not

based on QTextEdit. The new Qt classes that facilitate

the access to SQL databases don’t leave any tracks

on the KDE 3 core packages. This is more of an

advantage for the KDE programs of other users.

With its new releasable/movable windows, KDE 3

has added a feature, which Qt has had since its

version 2.2. If a program window consists of several

fragments, then those that have a small bar (as in

Figure 3) can be dragged onto the desktop. These

independent windows can even be shifted to

separate virtual desktops. In particular where several

monitors are used, with each one displaying another

virtual desktop, you can improve the clarity of control

of programs that need as much space as possible for

the main window.

Those of you who take the separation of windows

too far should take a deep breath – the re-integration

of window segments back into the main window

requires a steady hand. Shifting the window

fragments with the left mouse button, the tip of the

cursor must be exactly aligned with an edge of the

main window or one of the sub-windows integrated

therein.

New features thanks to Qt

The revised and completely new additions to Qt 3

account for the new features

in KDE 3. The desktop

environment thus receives,

for example, Xinerama

support without any

extra hassle. As well

as this, the new Qt 3

class QTextEdit (which

already provides a simple

Richtext editor) shortens

Class Contains “object-oriented programming” code, with which objects (for

example a button, a font or a whole application) can be produced. In order that

these very general objects can be individually created (so that they behave

differently), they contain class implementation functions, with which the

characteristics (properties) of an object (for example its colour) can be modified.

Objects can also “do things” (an application can close itself, a button can execute

an action), which can also be implemented by the functions (methods) of this class.

New applications

The many small and larger bug fixes and detail

improvements, which essentially constitute KDE 3,

Glyph A character from a font.

API A pplication P rogrammer’s I nterface. The answer to the question: “How can a

class be used without having to know about the implementation details?” –

expressed in a programming language. With C or C++, the API is concealed in a

class, normally in the header files with the ending “.h”. An API is actually only

complete with the appropriate API documentation, which describes what the class

and its functions do as well as which function arguments have which meaning etc?

Figure 4: Edutainment in KDE: Kgeo, Kvoctrain and Ktouch

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Xinerama : Representation of a virtual desktop on several monitors, whereby

windows can be dragged from one to the other. Individual windows can also be

situated “on the edge”, i.e. partly on one screen and partly on another (or several

others).

SQL database : A collection of data that is stored in the form of tables and can be

accessed with the assistance of a S tructured Q uery L anguage. Examples of Database

Management Systems(DBMS) on the SQL basis are mySQL, PostgreSQL and Oracle.

IMAP : I nternet M essage A ccess P rotocol. This is one possible way of accessing

emails stored on another computer with an appropriate utility program. From the

user’s point of view, it looks as if the mail boxes have been processed locally.

Figure 5: Pre school with Klettres

do not however hide the fact that the number of

applications has not (naturally enough) remained

constant. The new core package Kdeedu contains

nine learning-software programs – one for every

different level. The sensible and very applicable

vowel trainer Kvoctrain is extremely useful for

users of all levels – pupils and teachers alike – as

are the geometry drawing program Kgeo (Figure 4)

and the home planetarium Kstars. Pre-school

children can learn the letters of the French

alphabet with the Klettres–bear (Figure 5), and

then practice touch-typing with Ktouch. Using

these programs is not always child’s play – the

mode of operation of some applications is not self

evident without studying the documentation

(which is not always available).

remains just that: we unfortunately could not test the

announced improvements in the pre-version as the

program constantly crashed when trying to establish

a connection with the IMAP server.

Good things come in small

packages

The planning list for KDE 3 was long and not

everything on that list was implemented. There was

originally the idea of an icon server, which was to

cache icons during a KDE session, i.e. make icons

available that had already been used in an

application. The target of this was to accelerate the

loading time at the start of an application. However

in the course of the discussions, it turned out that

the problem could be solved without the use of an

additional help program. If icons are only loaded

when they are really needed by the application

(instead of all at the beginning), this not only speeds

up the starting time, but also saves yet another

server.

Whether all the new innovations and

improvements are interesting enough to warrant a

transfer to KDE 3.0 is for each individual user to

decide. Several KDE and Qt versions can also

peacefully co-exist next to each other if disk space in

not a limiting factor. The decision not to put its users

through any major changes (apart from transferring

to a new library version) is testimony to the fact that

the KDE team has become more mature and

responsible.

Easier operation

At the top of the list of applications that have

undergone the most improvement are (next to the

mandatory Konqueror) two very different

applications: Konsole and Kmail.

The first now also responds to the following

command line options: –tn terminal Typ , –– noframe ,

–– noscrollbar and nomenubar . While changing the

terminal type (for example on vt100 ), it is possible to

do without the shadow around the command line

field on a Konsole with a missing frame in order to

keep things as simple as possible. This is particularly

interesting for people who operate remotely,

potentially from machines with other operating

systems. This can be switched on again (the same for

a missing scroll bar) through the Settings menu item.

There is even a quick variation that doesn’t need the

menu bar: the key combination of Ctrl+Alt+M will do

the trick. On the strange side for a program of such a

modest range of functions is Konsole’s new “Tip of

the day” feature.

KMail for its part can now read mailboxes in the

Maildir format (one email per file, whereby a higher

ranking directory represents the mail folder). In

particular, this will make fans of the Qmail mail server

happy. On the other hand, the IMAP problem child

Info

Announcements on the new KDE releases:

http://www.kde.org/announcements/

Planned features for KDE 3.0: http://developer. kde.

org/development-versions/kde-3.0-features.html

Co-existence assistance for KDE 2 and 3: http://www.

pupeno.com.ar/runningkdes/

http://www.rons.net.cn/english/FSM/2kde3

http://www.kde.org/kde2-and-kde3.html

KDE 3.0

Supplier KDE.org

Web ttp://www.kde.org

For Grows community spirit

Against The benefits aren’t obvious

rating

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