Archive:Getting Started/Build/Qt: Difference between revisions

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Getting_Started/Build/Qt

Building KDE4 From Source/Qt

Tutorial Series	Getting Started
Previous	Getting_Started/Build/Requirements
What's Next	Getting_Started/Build/KdeSupport
Further Reading	n/a

Introduction

This page details the build requirements for Qt and some related packages. For most of these requirements it is preferable to use your distribution supplied packages, however in some case you will need to build some requirements yourself and this page will also explain how to do so.

Required Steps

You need to have completed the following steps:

Set up your [[../Environment|Build Environment]]
Selected your [[../Recipes|Build Recipes]]
Installed the [[../Requirements|System Requirements]]
Understand the [[../Requirements#Definitions|Requirements Table format]]

makeobj

Makeobj is a shell script to assist make.

**KDE Build Requirements**
Requirement	Stable Requires	Unstable Requires	Devel Pkgs?	Details
makeobj	r1215872	r1215872	No	A make helper shell script

It is a part of the kdesdk module and, while optional, is strongly recommended when building KDE modules. If you have kdesdk installed on your system then this version should be sufficient, but r1215872 is recommended when working with Git.

To install it download via WebSVN and install into your path somewhere, preferably ~/.bin. Once you have built kdesdk from source you should then remove this copy.

Qt

Qt is the development freamework that all KDE Software is built upon.

**KDE Build Requirements**
Requirement	Stable Requires	Unstable Requires	Devel Pkgs?	Details
Qt	>= 4.7.0	>= 4.7.0	Yes	The Qt development framework

Most distributions package a recent enough Qt to build KDE, although you may need to add an extra repository to do so. Building Qt can take a long time, so packages are preferred for a quick start.

At some stage, KDE master may switch to relying on a development version of Qt, or may require patches to Qt for bug-fixes that have not yet been released by Qt. In this case you may need to build your own copy of Qt to build KDE against. You can choose use either the main Qt repository on Gitorious or the KDE copy of Qt. You can choose to overwrite your system Qt install when doing so but this is not recommended. You are advised to set your build environment $QTDIR install directory to a local folder different to $KDEDIR to allow easy switching between Qt versions.

Please see the KDE Qt project page for further details. It is recommended to read the INSTALL file for more details.

Note that you need to install Qt and Phonon from Qt and then later to install Phonon KDE from git at the same location. This will ensure you get sound in Qt-based applications as well as in KDE ones.

Easy Recipe

Ensure you setup your environment $QTDIR to point to somewhere suitable, e.g. /usr/local.

cd <your source directory>
git clone kde:qt
cd qt
./configure <configure options, use $QTDIR as your 'installdir'>
nice make -j2 # for faster compiles use -j(X+1)' where X is your number of processor cores
make install

Full Recipe

cd <your source directory>
git clone git://anongit.kde.org/qt
cd qt
./configure <configure options>
nice make -j2 # for faster compiles use -j(X+1)' where X is your number of processor cores
make install

Troubleshooting

If ./configure produces errors about missing headers, run the following command before trying again:

QTDIR=`pwd` bin/syncqt

Make sure which qmake delivers something out of $QTDIR, e.g. /home/kde-devel/qt-kde/bin/qmake

If you get "error: X11/Xlib.h: No such file or directory", install the devel package of xorg (the actual name may vary between operating systems, for example it is xorg-dev on Ubuntu based systems such as Kubuntu).

If you get an error in the configure step about missing defines, check the value of $QMAKESPEC. Some distributions set this to point directly to the system-installed Qt. If unset QMAKESPEC solves the problem, you probably want to add it to the ~/.bashrc script.

If you get an error ".pch/debug-shared/QtCore", this is because Qt-4.3 enables precompiled headers if your gcc supports it, but for some reason it doesn't work for you. If you use distcc, configure qt with -no-pch. If you use icecream, update to the latest icecream from svn trunk.

Try running any Qt program, like assistant.

Generating local API documentation

It's nice to have the Qt documentation locally for nice integration with KDevelop, and doing this is really quite easy:

cd $KDE_SRC/qt
make docs
./config.status
make install

Note that it is necessary to do this only once, even if you rebuild Qt later.

DBusMenu-Qt

DBusMenu-Qt is a library providing a Qt implementation of the DBusMenu spec.

**KDE Build Requirements**
Requirement	Stable Requires	Unstable Requires	Devel Pkgs?	Details
DBusMenu-Qt			Yes	A Qt implementation of the DBusMenu spec.

Your distribution packages should be sufficient for this requirement. If you need to build your own copy using the Easy or Full Recipe then either download a tarball form the project home page or use the following bazaar command:

bzr branch lp:libdbusmenu-qt

You need json to build the tests.

Next Step

Once Qt has been installed it is time to install [[../KDE_Support|KDE Support]]