Development/Tutorials/KDE4 Porting Guide (fi): Difference between revisions

Revision as of 08:09, 17 January 2008

Development/Tutorials/KDE4_Porting_Guide

Esipuhe

Tämä perehdytys on tarkoitettu ohjelmistokehittäjille auttaakseen heitä siirtämään heidän Qt3/KDE3 ohjelmistonsa Qt4/KDE4 ympäristöön. KDE3 ohjelmien siirron ei välttämättä tarvitse olla hankala prosessi. On olemassa valmiina monia komentojonoja ja dokumentaatio lähteitä tämän helpottamiseksi.

Käsitteet

Tämän perehdytyksen ohjeissa käytetään seuraavia käsitteitä:

program kuvaa suoritettavaa tiedostoa, ohjelmaa
path kuvaa polkua
file kuvaa tiedostoa
$SVN on täydellinen polku paikalliseen kopioon KDE:n SVN kopiosta

CMake

KDE3:a poiketen KDE4 ohjelmat käännetään CMakea apuna käyttäen. Helpoin tapa siirtää "autotools system" CMakelle on käyttää apuna am2cmake-komentojonoa joka löytyy kdesdk moduulin alta cmake/scripts-hakemistosta. am2cmake-luo, riippuen vanhan käännösjärjestelmän tiedostojen määrästä, joukon CMakeLists.txt-tiedostoja.

Esimerkiksi, jos lähdekoodisi sijaitsee /path/to/src-hakemistossa, niin: % cd /path/to/src % $SVN/trunk/KDE/kdesdk/cmake/scripts/am2cmake --kde4 Suorita am2cmake --help tarkistaaksesi tarvitsetko --kde4 valitsinta.

Samasta $SVN/trunk/kde/kdesdk/scripts-hakemistosta löytyy myös cmakelint.pl-niminen työkalu jolla voit tarkistaa uusien CMakeList.txt-tiedostojen mahdolliset ongelmat. Käyttö: % cd /path/to/src % $SVN/trunk/KDE/kdesdk/scripts/cmakelint.pl CMakeLists.txt Tai, jos tarkistat kaikki CMakeLists.txt lähdekoodi hakemistostasi: % cd /path/to/src % find . -name CMakeLists.txt | \

 xargs $SVN/trunk/KDE/kdesdk/scripts/cmakelint.pl

Qt4 API

An overview of the Qt3 to Qt4 transition is provided in Trolltech's "Moving from Qt 3 to Qt 4" paper. This document provides an excellent overview into the major functionality changes with Qt4 and is highly recommended.

The follow-on "Porting to Qt 4" page gives an amazingly detailed description of the porting process, along with a list of the changes in the classes and functions.

These documents describe a tool provided by Trolltech called qt3to4 that can help port the Qt parts of your code from Qt3 to Qt4, using compatibility functions. Run qt3to4 as follows: % $SVN/trunk/qt-copy/bin/qt3to4 [options] <Infile>, [Infile], ... Infile can be a source file or a project file. If you specify a project file, ending with '.pro' or '.pri', qt3to4 will port all files specified in that project.

For more information, run qt3to4 with the "--help" option or visit the "qt3to4-The Qt 3 to 4 Porting Tool" page.

Additionally, there is a program called remove-qt3-support.pl in the kdesdk module that will search and replace lots of deprecated Qt3 stuff for you. Simply run this program without any options in the source directory. % $SVN/trunk/KDE/kdesdk/scripts/qt4/remove-qt3-support.pl

Chances are that some Qt3 classes will still remain in the code, so make sure your top-level CMakeLists.txt file defines the QT3_SUPPORT and QT3_SUPPORT_WARNINGS macros for the Qt headers, like so: add_definitions (-DQT3_SUPPORT -DQT3_SUPPORT_WARNINGS)

KDE4 API

Much of the porting effort consists of simply renaming class names and header files. Since it would be rather tedious to change all these by hand, there is a handy script in the scripts/qt4 directory of kdesdk called adapt-to-kde4-api.pl. This will scan all your files and create a diff output which can then be used to patch your code.

Once that simple code substitution has been done, you will still have to go through your code to port to, for example, the new KAction API. Documentation about all API changes is kept in the KDE4PORTING.html file in the kdelibs module.

Qt Designer UI Files

Qt designer ".ui" files created using Qt3 must be converted to the new Qt4 format. This can be done using the uic3 program available from your Qt4 installation.

% $SVN/trunk/qt-copy/bin/uic3 -convert file.ui > foo.ui % mv foo.ui file.ui

Or, if you prefer a graphical tool, you can use Qt4's designer program

% $SVN/trunk/qt-copy/bin/designer file.ui (you can save file.ui over top itself, or save to a new file)

Warning

Beware, the conversion process loses any custom slots, table columns, etc. So, you may need to put some stuff back by hand.

You should also run the fixuifiles program from the kdesdk module, it performs cleanups and sanity checks: % $SVN/trunk/KDE/kdesdk/scripts/fixuifiles

D-Bus

Instead of DCOP in KDE3, KDE4 now uses D-Bus for its interprocess communication. Porting from DCOP to D-Bus is a large topic that is covered in great detail in the Porting to D-Bus tutorial.

For more information, please see all our D-Bus tutorials.

Icons

KDE4 uses the freedesktop.org icon naming specification as the basis for icon names. This means that both the icons that ship with KDE4 (Oxygen) as well as components in kdelibs that use icons follow this specification.

Porting your app from the icon names used in KDE3 to the ones used in KDE4 is as easy as running the adapt-to-icon-spec.py script from the root directory of your project and follow the instructions on screen.

The script automatically converts confirmable positives (e.g. uses of KIcon or KIconLoader), skips confirmable negatives and prompts for what to do with possible positives. It shows the latter with additonal context if desired and makes it a simple matter of pressing 'y' or 'n' for the possible hits to complete the porting.

Internationalization

To create your ".pot" file, copy the commands from the 'messages' rule in your projects Makefile.am to a shell script called Messages.sh. You may assume the same variables ($PREPARETIPS, $XGETTEXT, $podir, etc.) still exist, but keep in mind the differences between Makefile and shell script syntax.

Also be careful that if you use the -k parameter with $XGETTEXT, you will need to explicitly list all variants that you use.

For example, the 'messages' creation rule: messages: rc.cpp

       rm -f tips.cpp
       $(PREPARETIPS) > tips.cpp
       $(XGETTEXT) -ktranslate *.cpp *.h -o $(podir)/kmail.pot
       rm -f tips.cpp

becomes the following Messages.sh script:

! /usr/bin/env bash

$PREPARETIPS > tips.cpp $XGETTEXT -ktranslate:1,1t -ktranslate:1c,2,2t *.cpp *.h -o $podir/kmail.pot rm -f tips.cpp

Do's and Don'ts

Do NOT use the old-style socket classes.
Do NOT use QPtrList, and in general, setAutoDelete()
Do NOT make use of raster operations.
Do NOT do code painting on widgets outside paint events.
Try not to use QHBox, QVBox, QGrid. Prefer layouts instead.
Do NOT play with frames of groupboxes, labels, or lineedits to fake a different widget. Use the appropriate widget instead. e.g., instead of setting a label to have a sunken lineedit border, how about using a readonly KLineEdit instead? And instead of using a KLineEdit without a border for a copyable widget, use KActiveLabel.
Do NOT use a groupbox without border to group widgets! Just use a layout.

Resources

Documentation

Other Help

#kde4-devel on irc.freenode.net

@@ Line 12: / Line 12: @@
 ==CMake==
-Unlike KDE3, KDE4 applications will be built with the help of [[Development/Tutorials/CMake | CMake]]. The easiest way to port your autotools system to CMake is with the help of the {{program|am2cmake}} script which can be found in the {{path|cmake/scripts}} directory of the [http://websvn.kde.org/trunk/KDE/kdesdk/ kdesdk] module. This will create a series of {{path|CMakeLists.txt}} files alongside your old buildsystem files.
+KDE3:a poiketen KDE4 ohjelmat käännetään [[Development/Tutorials/CMake | CMakea]] apuna käyttäen. Helpoin tapa siirtää "autotools system" CMakelle on käyttää apuna {{program|am2cmake}}-komentojonoa joka löytyy [http://websvn.kde.org/trunk/KDE/kdesdk/ kdesdk] moduulin alta {{path|cmake/scripts}}-hakemistosta. {{program|am2cmake}}-luo, riippuen vanhan käännösjärjestelmän tiedostojen määrästä, joukon {{path|CMakeLists.txt}}-tiedostoja.
-For example, if your source code is located in {{path|/path/to/src}} then:
+Esimerkiksi, jos lähdekoodisi sijaitsee {{path|/path/to/src}}-hakemistossa, niin:
 <code bash>
 % cd /path/to/src
 % $SVN/trunk/KDE/kdesdk/cmake/scripts/am2cmake --kde4
 </code>
-Run <tt> am2cmake --help</tt> to check whether you need the <tt>--kde4</tt> flag.
+Suorita <tt> am2cmake --help</tt> tarkistaaksesi tarvitsetko <tt>--kde4</tt> valitsinta.
-There is also a tool that looks in your resulting {{path|CMakeList.txt}} files for potential problems.  This tool called {{program|cmakelint.pl}} is located in {{path|$SVN/trunk/kde/kdesdk/scripts}}.  Use it like so:
+Samasta {{path|$SVN/trunk/kde/kdesdk/scripts}}-hakemistosta löytyy myös {{program|cmakelint.pl}}-niminen työkalu jolla voit tarkistaa uusien {{path|CMakeList.txt}}-tiedostojen mahdolliset ongelmat. Käyttö:
 <code bash>
 % cd /path/to/src
 % $SVN/trunk/KDE/kdesdk/scripts/cmakelint.pl CMakeLists.txt
 </code>
-Or, to run it over your entire source directory:
+Tai, jos tarkistat kaikki {{path|CMakeLists.txt}} lähdekoodi hakemistostasi:
 <code bash>
 % cd /path/to/src