Getting Started/Set up KDE 4 for development (es)

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Esta página está siendo traducida en estos momentos.
Aviso

Configurar KDE 4 para el desarrollo

Serie	Getting Started
Requisitos previos	Build KDE 4 (es)
Siguiente	Otros temas sobre desarrollo
Lectura avanzada	n/d

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Esta página da por hecho que has compilado kdelibs, kdepimlibs y kdebase según estas instrucciones
Nota

Lanzar aplicaciones y sesiones de KDE 4

Al empezar el desarrollo de KDE 4, generalmente hay tres opciones disponibles:

Podrías ejecutar aplicaciones de KDE 4 al mismo tiempo que otras aplicaciones de tu entorno de escritorio actual.
Podrías embeber una sesión de KDE 4 en tu entorno de escritorio actual.
Podrías ejecutar KDE 4 como el único entorno de escritorio de la máquina.

Las tres opciones se describen en las secciones a continuación.

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Si encuentras errores al ejecutar una aplicación kde4, como:

 Qt: Session management error: Could not open network socket
 QMutex::lock: Deadlock detected in thread -1241241936

o si al ejecutar startkde se queda colgado, lee este artículo para una solución provisional.

Nota

Lanzar aplicaciones KDE 4

Usar la consola normal con sux

Para este método, se necesita la herramienta sux (http://fgouget.free.fr/sux/sux-readme.shtml). sux está disponible en la mayoría de distribuciones. De lo contrario podrías utilizar el método consola normal sin sux. sux permite cambiar a otro usuario con una gestión implícita de los detalles de la transferencia de las X (exportación de autenticación y DISPLAY) de una forma limpia y simple.

Para iniciar sesión, escribe sux - kde-devel

El .bashrc debería configurar correctamente las variables de entorno y todo lo demás. Para iniciar una aplicación, simplemente escribe su nombre; por ejemplo kwrite

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Si aparecen errores acerca de tipos mime inexistentes o algo parecido, intenta lo siguiente:

ejecutar unset XDG_DATA_DIRS ; kbuildsycoca4

Nota

Usar la consola normal sin sux

El método más sencillo para lanzar aplicaciones de KDE 4 es usar su para iniciar sesion como el usuario kde-devel y después simplemente inicia cualquier aplicación de KDE 4 desde la línea de comandos. Para iniciar sesión, escribe su - kde-devel y después, trás introducir la contraseña export DISPLAY=:0

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Exportar la variable `DISPLAY` es necesario para que las aplicaciones de KDE 4 aparezcan en el escritorio normal de KDE 3.
Nota

El .bashrc debería configurar correctamente las variables de entorno y todo lo demás. Para iniciar una aplicación, simplemente escribe su nombre; por ejemplo kwrite

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Si aparecen errores acerca de tipos mime inexistentes o algo parecido, intenta lo siguiente:

ejecutar unset XDG_DATA_DIRS ; kbuildsycoca4

Nota

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Nota

Usar SSH

La manera más simple de ejecutar una aplicación de KDE con SSH en tu entorno de escritorio actual es tener una sesión X-aware en la consola como usuario kde-devel así: ssh -X kde-devel@localhost Ahora puedes ejecutar aplicaciones de KDE como normalmente lo harías, por ejemplo: kwrite Las dos lineas pueden ser combinadas: ssh -X kde-devel@localhost kwrite

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Si esto te da algún error, intenta con los consejos de la parte superior.
Nota

Iniciar sesión sin contraseña

Antes de que podamos hacer algo serio con este método, es necesario crear una sesión sin contraseña. Para empezar, ejecuta el siguiente comando como el usuario regular de tu escritorio: ssh-keygen -t rsa Presiona ENTER trés veces para aceptar la ruta ~/.ssh/id_rsa y la clave vacía. Ahora, copia la única linea en~/.ssh/id_rsa.pub que aparece después de ejecutar este comando:cat ~/.ssh/id_rsa.pub Después de copiar esa linea, regresa dentro del usuario kde-devel y pon la linea copiada en el archivo $HOME/.ssh/authorized_keys:

ssh -X kde-devel@localhost $HOME/kde/bin/kwrite \
 $HOME/.ssh/authorized_keys

Pega la linea, guarda el archivo y cierra KWrite. Ahora, intenta ejecutar KWrite otra vez con el mismo comando SSH; no deberías de necesitar introducir una contraseña desde ahora: ssh -X kde-devel@localhost $HOME/kde/bin/kwrite

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Usando una sesión SSH sin contraseña tiene muchos "riesgos de seguridad", así que asegurate de proteger tu archivo `~/.ssh/id_rsa` restringiendo el acceso con `chmod og-xrw ~/.ssh/id_rsa`(although the file should have these permissions when it is created)
Aviso

El archivo .desktop de SSH

Si quieres ser capaz de ejecutar aplicaciones más fácilmente que ejecutarlas con un comando SSH desde la consola, una manera de hacerlo es crear archivos .desktop que ssh dentro de la otra sesión.

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Esto será útil únicamente si tu escritorio soporta archivos .desktop, pero por lo menos KDE y GNOME lo hacen.
Nota

Puedes iniciar con un archivo .desktop existente como una plantilla (como alguno que esté en tu escritorio o puedes crear uno desde el inicio. La idea principal es establecer la ruta de la consola con este comando: ssh -X kde-devel@localhost $HOME/kde/bin/

Un archivo .desktop normal que ejecuta KWrite tendría el siguiente contenido:

[Desktop Entry] Categories=Qt;KDE;TextEditor; Comment= DocPath=kwrite/index.html Encoding=UTF-8 Exec=ssh -X kde-devel@localhost /home/kde-devel/kde/bin/kwrite %U GenericName=Text Editor Icon=kwrite InitialPreference=8 MimeType=text/plain Name=KWrite (kde-devel) Path= StartupNotify=false Terminal=false TerminalOptions= Type=Application X-DBUS-StartupType=Multi X-DCOP-ServiceType=non X-KDE-StartupNotify=true X-KDE-SubstituteUID=false X-KDE-Username=

Tip
Las aplicaciones ejecutadas usando SSH de esta manera no realizan las respuestas correctas de lanzamiento, por lo que probablemente querrás deshabilitar el registro de lanzamiento de tus archivos .desktop

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Para crear correctamente un archivo .desktop para una aplicación de KDE 4 usando este método, el paquete de la aplicación tiene que haber sido instalado dentro del directorio `~/kde/bin` usando el comando `cmakekde`
Nota

Lanzando sesiones de KDE 4

Anidando una sesión de KDE 4

Nested

En lugar de usar una nueva X virtual para desarrollar software, puedes usar Xephyr para anidar tu sesión de KDE 4 dentro de tu KDE 3 actual u otro entorno X11.

Puedes hacer esto también con xnest, pero como xnest no maneja extenciones como Render, mucha gente prefiere Xephyr.

Si quieres tener una sesión mínima de KDE funcionando, simplemente lanza Xephyr (disponible en Kubuntu como xserver-xephyr; los usuarios de Gentoo sólo compilen x11-base/xorg-server con USE="kdrive"):

Xephyr :1 -extension GLX &

Ahora puedes lanzar KDE:

export DISPLAY=:1
/path/to/kde4/bin/startkde-modified &

startkde-modified es una copia de startkde-script que incluye las siguientes lineas en la parte de arriba:

export KDEDIR=`kde4-config --prefix` export LD_LIBRARY_PATH=$KDEDIR/lib export PATH=$KDEDIR/bin/:$PATH export KDEHOME=~/.kde4

Puedes usar Xephyr con KDM mediante el protocolo Xdmcp y simplemente una nueva sesión de KDE 4 para KDM.

En Kubuntu, lo puedes habilitar cambiando:

[Xdmcp]


 Whether KDM should listen to incoming XDMCP requests.
 Default is true

Enable=false

en /etc/kde3/kdm/kdmrc a:

[Xdmcp]


 Whether KDM should listen to incoming XDMCP requests.
 Default is true

Enable=true

y ajustar tu /etc/kde3/kdm/Xaccess para permitir el acceso a tu máquina local.

Adicionalmente deberías segurarte de configurar directivas de bloqueo de puerto en toda las interfaces externas para el puerto Xdmcp si esto lo estás haciendo en una laptop o una PC en un entorno poco confiable.

Si haces esto, simplemente lanza Xephyr:

Xephyr -query localhost :1 -host-cursor -screen 1024x768&

Donde -host-cursor trata de reusar el cursor principal y -screen establece las dimenciones de pantalla.

Nota: Si obtienes muchos errores de rechazo de conexión, podrías querer usar la opción -ac de Xephyr. Por ejemplo:

Xephyr -ac :1&

Otra opción a tratar si obtienes muchos errores de rechazo de conexión es que tal vez necesites acceso a tu usuario kde-devel para X server. Como root o usando sudo ejecuta:

xhost +local:kde-devel

Si no tienes Xephyr, puedes usar también Xnest:

Xnest -ac :1& export DISPLAY=:1


This section needs improvements: Please help us to cleanup confusing sections and fix sections which contain a todo

Sping 00:25, 9 April 2007 (CEST)

Yo use este para mi script de inicio "nested_kde4.sh":

#! /bin/bash
NESTED_KDE_DISPLAY_BACKUP=$DISPLAY
export DISPLAY=:0
Xephyr :1 -screen 1024x768 &
export DISPLAY=:1
$HOME/kde/bin/startkde-modified &
export DISPLAY=${NESTED_KDE_DISPLAY_BACKUP}

Si obtienes:

"Call to lnusertemp failed (temporary directories full?).
 Check your installation."

Intenta esto:

mkdir /var/tmp/kde-devel-kde4

Este código asume que trabajas con el usuario "kde-devel".

Note
En la mayoría de los casos necestas reemplazar "startkde-modified" con "startkde"

Solitary KDE 4 session

Solitary

To run a full KDE 4 desktop environment session, you can either start it from the command line as you normally would, with something like this:

X :1 & export DISPLAY=:1
startkde

Note
If the X server refuses the connection saying something like: `Xlib: connection to ":1.0" refused by server`, try `X -ac :1` instead.

or you can can add it to your login manager. If you are using KDM (or a compatible login manager) this is done by creating a .desktop file in either `kde-config --prefix`/share/apps/kdm/sessions/ or in /usr/share/xsessions/. The easiest thing to do is to copy an existing kde.desktop file and name it kde4.desktop. Open this new .desktop file in a text editor and change the Exec, TryExec and Name entries to look something like this:

Exec=$HOME/kde/bin/startkde TryExec=$HOME/kde/bin/startkde Name=KDE4

Replace $HOME/kde in the example above with the prefix you are installing KDE4 into.

After restarting the login manager (Alt+e in KDM) this new entry should appear in the sessions menu.

Note
You should have path to 'qdbus' program (usually it is $QTDIR/bin) in your $PATH to login successfully. If it is not there, you'll get an error message "Could not start DBus. Check your installation."

Development tasks

KDevelop

This section will explain how to use KDevelop 3.4 to develop KDE 4 applications. If you have any questions, corrections or rants about this section, please post them on the discussion page.

Prerequisites

You need at least KDevelop 3.4 for this, which is still a KDE 3 application. Versions lower than 3.4 do not have Qt 4 support among other things. The KDE 4 version of KDevelop is not yet ready for serious development. You can get KDevelop at the KDevelop homepage. Make sure you install KDevelop like all other KDE 3 applications, not with your kde-devel user.

You also need the lastest GDB version, which is currently 6.6.0.

You need to have the kdelibs API documentation locally, which is described in the build instructions.

You also need ctags, htdig, htmerge and htsearch. valgrind and callgrind can also be useful.

Be sure you followed the steps in the KDE 4 build instructions and have a working KDE 4 environment. Make sure simple KDE 4 applications like Konsole or KWrite can be started from the command line of the kde-devel user without problems.

The following steps are all done with the kde-devel user. You need to login as that user by typing su - kde-devel.

Setting up the environment

KDevelop has no native support for CMake projects. Fortunately, CMake has the ability to generate KDevelop project files itself. In order to do this, you need to pass the -GKDevelop3 flag to the cmake command. This tells CMake to generate project files for KDevelop alongside the normal makefiles. The best way to do this is to modify your cmakekde function in your .bashrc. Just change cmake $srcFolder -DCMAKE_INSTALL_PREFIX=$KDEDIR \ -DCMAKE_BUILD_TYPE=debugfull&& \ make && \ make install; to cmake $srcFolder -GKDevelop3 -DCMAKE_INSTALL_PREFIX=$KDEDIR \ -DCMAKE_BUILD_TYPE=debugfull&& \ make && \ make install;

After you have done that, re-login so that the changes to the .bashrc file take effect. Then you need to rerun cmakekde in the (root) build directory of the project you want to work on with KDevelop (if you didn't use -GKDevelop3 on the building step). For example, if you want to work on Konsole, which lives in kdebase, you need to run cmakekde in the $KDE_BUILD/KDE/kdebase directory. This unfortunately completely rebuilds everything, but only once when you change the generator.

Since all environment variables of the kde-devel user are KDE 4 specific, these need to be set back to match your KDE 3 environment before starting KDevelop. A simple way to do this is to add the following function to your .bashrc:

function start3app {


 mkdir -p /tmp/$USER-kde
 export PATH=/opt/kde3/bin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/bin/X11:/usr/games 
 export LD_LIBRARY_PATH= 
 export KDETMP=/tmp/$USER-kde 
 export KDEVARTMP=/var/tmp/$USER-kde 
 export KDEHOME=$HOME/.kde 
 export KDEDIR=/usr 
 export KDEDIRS=$KDEDIR 
 export DISPLAY=:0 
 eval "$@"
 source $HOME/.bashrc   #Reset environment variables again

}

The PATH and LD_LIBRARY_PATH variables are taken from the KDE 3 user, and they may be different on your system. Type echo $PATH and echo $LD_LIBRARY_PATH as normal KDE 3 user to get these values. The above function assumes that KDE 3 is installed in the /usr prefix, as it is the case on Debian-based systems. If your KDE 3 is installed to a different prefix, you need to change the line setting KDEDIR accordingly. Here's an example how you find out your KDE installation prefix; in this example it is /opt/kde3:

kde-config --prefix /opt/kde3

Now you should be able to start KDevelop by typing start3app kdevelop. Do that now.

Tip
You can start any KDE 3 application with the `start3app` function. Useful candidates include Kompare and kdesvn. However, you can not start KDbg this way to debug KDE 4 applications, since then the environment variables for the debugged application are wrong.

TroubleShooting

Symptome: kdevelop says "cannot talk to klauncher". You cannot open a file.

Solution: add your KDE library path to LD_LIBRARY_PATH, e.g.:

export LD_LIBRARY_PATH=/opt/kde3/lib

Setting up KDevelop

Now that KDevelop has started, you need to adjust a few settings. Go to Settings->Configure KDevelop...->Documentation for this. Remove all entries that are not relevant to KDE 4 coding.

Note
Although environment variables like $HOME are used in this section, you should replace them with real paths because KDevelop does not resolve environment variables.

Optionally, you can add the kdelibs API documentation. You must create it before. Then add the documentation by clicking Add.... In this dialog, use the following settings:

Type: Doxygen Documentation Collection (needs to be set first)
Location: $KDE_SRC/KDE/kdelibs/kdelibs-apidocs/index.html

Now add the Qt API documentation, using the following settings:

Type: Qt Documentation Collection (needs to be set first)
Location: $HOME/qt-copy/doc/html/qt.dcf

After you have added kdelibs and Qt API documentation, make sure all checkboxes (TOC,Index and Search) are enabled. Then, go to the Full Text Search tab and make sure the paths to the htdig, htmerge and htsearch executables are correct. You can then close the settings dialog.

Now it is time to open the project you want to work on by clicking Project->Open Project.... The project files are located in the build directory. For example, if you want to work on Konsole, you need to open $KDE_BUILD/KDE/kdebase/apps/konsole/konsole.kdevelop. You now need to adjust a few project-specific settings in Project->Project Options. You need to do this every time you start to work on a different project.

Note

Sometimes, a KDevelop project file is not present for the folder you want to work on.

This can have several reasons, it depends on how the CMake files are written. Usually, CMake files which have a project(projectname) statement in them should work fine. Once you are familiar enough with CMake, you can try adding the statement.

A workaround for this is to simply use the KDevelop project file of the parent folder, or even higher. In this case, you need to use the Make Active Directory entry in the context menu of the File Selector sidetab. With this, you can ignore the other unwanted folders when building and installing.

C++ Support->Code Completion

Here you need to add code completion databases for Qt and kdelibs, and more if you like, for example you might need a database for kdepimlibs when working on kdepim.

For kdelibs, click the Add... button and choose KDevelop Custom Directory PCS Importer, then add your KDE include directory ($HOME/kde/include) to the list and proceed. You can use the file selection dialog and the Add button to add it.

Now, add the database for Qt 4 by selecting KDevelop Qt4 PCS Importer this time. You need to select the Qt 4 include directory, which is $HOME/qt-copy/include.

Note
The Qt4 PCS Importer is only needed if you didn't install Qt4, i.e. you use it directly from the build directory. The drawback of using the Qt4 importer is that it doesn't show progress and the application seems to hang while it imports. The alternative is to use the Custom Directory PCS Importer for this too

C++ Support->Qt Options

Check Enable Qt options and choose Qt4 as your version. Set the QMake Binary path to $HOME/qt-copy/bin/qmake. Then choose Qt 4 style as Qt include syntax. Use $HOME/qt-copy/bin/designer as Designer Binary. Make sure to use the Change Plugin Paths dialog to add the plugin directory from KDE so you see the KDE widgets when designer is started. To do this add $HOME/kde/lib/kde4/plugins to the lineedit and then click the Add button.

Run Options

Make sure you use the correct binary as Executable. For example, if you want to run Konsole, this is $KDE_BUILD/KDE/kdebase/apps/konsole/src/konsole. You should add --nofork to the Debug Arguments or debugging some applications like KMail will not work at all.

Because the start3app functions changes some environment variables, you need to change them back here so the KDE 4 applications can be run without problems from within KDevelop.

For some applications, like Konsole, this is not strictly necessary, but others like KMail will crash if you do not change this.

Simply click the Add / Copy button to add new environment variables. You will need the following, which are the same as in your .bashrc:

Name	Value
KDEHOME	$HOME/.kde4
PATH	$KDEDIR/bin:$QTDIR/bin:/usr/local/bin:$PATH
LD_LIBRARY_PATH	$KDEDIR/lib:$QTDIR/lib:$LD_LIBRARY_PATH
KDETMP	/tmp/$USER-kde4
KDEVARTMP	/var/tmp/$USER-kde4
KDEDIR	$HOME/kde
KDEDIRS	$KDEDIR
LD_BIND_NOW	42

Build Options->Build

Make sure the correct build directory is selected. Again, for Konsole, this would be $KDE_BUILD/KDE/kdebase/apps/konsole.

Build Options->Make

You might want to check Abort on first error. You also might want to add VERBOSE= or VERBOSE=1 to Additional make options to control the level of verbosity for the build process.

If you have more than one processor or if you have access to an icecream cluster, you might want to check the Run multiple jobs option and set the Number of simultaneous jobs to the number of available processors. This increases the compile speed. It is the same as the -j option for make.

Formatting

You should set all options here to match the coding style of the project you are working on.

CTags->General

You need to correctly set the Path to ctags binary, which is /usr/bin/ctags on Debian-based systems.

You probably want to enable the When more than one hit, go directly to the first option.

Now you have finished adjusting your project-specific settings. Now you should remove some plugins you do not need, in Settings->Configure Plugins.... I for example disable the following plugins:

Abbreviation Expansion, Code Snippets, Doxygen Support, Embedded Konsole, File Tree, Final Packaging Support, "Open with" Menu Addon, QuickOpen, Regular Expression Tester, Scripting, Security Checker, Shell Filtering and Insertion, Text Structure and Tools Menu Addition.

You should at least disable the bold ones.

Now, open any source file if none is open already. This will enable the Settings->Configure Editor... entry, where you need to set the tab options to match the tab style used by the project you are working on. The important settings are:

Appearance->Borders->Show line numbers: Should be checked.
Appearance->Borders->Show icon border: Should be checked.
Editing->Tabulators
Editing->Static Word Wrap->Show marker: Should be checked
Indentation->Automatic Indentation->Indentation mode: Should be C Style
Indentation in general

In the mainwindow, click the CTags tab on the bottom tabbar, then click the Regenerate button to create a CTags database for easier source code navigation.

Now you have completed all essential configuration, congratulations!

Using KDevelop

Refer to the KDevelop manual for general help using KDevelop. The following section will only deal with special cases for KDE 4.

Debugging

KDE apps have many symbols, which means that you need a lot of memory to get a decent loading times for debugging. To quote a GDB developer: "I would be reluctant to debug KDE on something with <1GB RAM." If the stepping function of the debugger is slow for you, try the following tips:

Hide local variables. The Locals part of the variable tab on the left causes a big slowdown when stepping if you have many local variables. Simple collapse the Locals part of the tree, the local variables are then not updated every step. You can still examine variables by using the Evaluate expression function.
Use the patch at http://bugs.kde.org/show_bug.cgi?id=143977. It prevents the update of the framestack widget at each step, speeding up stepping considerably. The patch introduces some minor glitches, which is why it is not yet commited.

Note
KDevelop does not yet support modifing the CMake build system. This means you can not use KDevelop to add or remove files from the project or to change any other aspect of your project's build process. You need to modify the CMake files by hand and then rerun `cmakekde` instead. Read the CMake tutorial to learn how to do this.

Tip
When you work on libraries, you first need to install them before you can test or debug your changes. Since this is cumbersome and time consuming, you should create symlinks (ln -s) pointing from the build directory to the installation directory for all affected libraries. Often, even simple programs use libraries internally, for example the settings dialog of Konsole is really a library.

Getting Started/Set up KDE 4 for development (es)

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