summaryrefslogtreecommitdiffstats
path: root/doc/src/emb-features.qdoc
diff options
context:
space:
mode:
Diffstat (limited to 'doc/src/emb-features.qdoc')
-rw-r--r--doc/src/emb-features.qdoc147
1 files changed, 147 insertions, 0 deletions
diff --git a/doc/src/emb-features.qdoc b/doc/src/emb-features.qdoc
new file mode 100644
index 0000000..67f92a5
--- /dev/null
+++ b/doc/src/emb-features.qdoc
@@ -0,0 +1,147 @@
+/****************************************************************************
+**
+** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
+** Contact: Qt Software Information (qt-info@nokia.com)
+**
+** This file is part of the documentation of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** No Commercial Usage
+** This file contains pre-release code and may not be distributed.
+** You may use this file in accordance with the terms and conditions
+** contained in the either Technology Preview License Agreement or the
+** Beta Release License Agreement.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Nokia gives you certain
+** additional rights. These rights are described in the Nokia Qt LGPL
+** Exception version 1.0, included in the file LGPL_EXCEPTION.txt in this
+** package.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 3.0 as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU General Public License version 3.0 requirements will be
+** met: http://www.gnu.org/copyleft/gpl.html.
+**
+** If you are unsure which license is appropriate for your use, please
+** contact the sales department at qt-sales@nokia.com.
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+/*!
+ \page fine-tuning-features.html
+ \title Fine-Tuning Features in Qt
+ \ingroup qtce
+ \ingroup qt-embedded-linux
+ \brief Describes how to reduce the size of Qt libraries by selecting only
+ the features that are needed.
+
+ In many cases, only a fixed set of applications are deployed on an
+ embedded device, making it possible to save resources by minimizing
+ the size of the associated libraries. The Qt installation can easily
+ be optimized by avoiding to compile in the features that are not
+ required.
+
+ \tableofcontents
+
+ A wide range of features are defined, covering classes and technologies
+ provided by several of Qt's modules.
+ You can look up the different feature definitions in the
+ \c{src/corelib/global/qfeatures.txt} file within the Qt source
+ distribution.
+
+ \section1 Simple Customization
+
+ \section2 Embedded Linux
+
+ To disable a particular feature, just run the \c configure script
+ for Qt for Embedded Linux with the \c -no-feature-<feature> option.
+ For example:
+
+ \snippet doc/src/snippets/code/doc_src_emb-features.qdoc 1
+
+ The feature can easily be enabled again by running \c configure
+ with the \c -feature-<feature> option.
+
+ See also \l{Qt Performance Tuning}.
+
+ \section2 Windows CE
+
+ To disable a particular feature, just run the \c configure script
+ with the set of required \c -D<feature> options. For example,
+ you can use the \c -D option to define \c{QT_NO_THREAD}:
+
+ \snippet doc/src/snippets/code/doc_src_emb-features.qdoc 0
+
+ The \c -D option only creates a Qt internal define. If you get linker
+ errors you have to define \c QT_NO_THREAD also for your project.
+ You can do this by adding \c DEFINES += \c QT_NO_THREAD to your
+ \c .pro file.
+
+ See also \l{Qt Performance Tuning}.
+
+ \section1 Managing Large Numbers of Features
+
+ If you want to disable a lot of features, it is more comfortable
+ to use the \c qconfig tool.
+ You can disable a \e set of features by creating a custom
+ configuration file that defines the preferred subset of Qt's
+ functionality. Such a file uses macros to disable the unwanted
+ features, and can be created manually or by using the \c qconfig
+ tool located in the \c{tools/qconfig} directory of the Qt source
+ distribution.
+
+ \note The \c qconfig tool is intended to be built against Qt on
+ desktop platforms.
+
+ \bold{Windows CE:} The Qt for Windows CE package contains a \c qconfig
+ executable that you can run on a Windows desktop to configure the build.
+
+ \image qt-embedded-qconfigtool.png
+
+ The \c qconfig tool's interface displays all of Qt's
+ functionality, and allows the user to both disable and enable
+ features. The user can open and edit any custom configuration file
+ located in the \c{src/corelib/global} directory. When creating a
+ custom configuration file manually, a description of the currently
+ available Qt features can be found in the
+ \c{src/corelib/global/qfeatures.txt} file.
+
+ Note that some features depend on others; disabling any feature
+ will automatically disable all features depending on it. The
+ feature dependencies can be explored using the \c qconfig tool,
+ but they are also described in the \c{src/corelib/global/qfeatures.h}
+ file.
+
+ To be able to apply the custom configuration, it must be saved in
+ a file called \c qconfig-myfile.h in the \c{src/corelib/global}
+ directory. Then use the \c configure tool's \c -qconfig option
+ and pass the configuration's file name without the \c qconfig-
+ prefix and \c .h extension, as argument.
+ The following examples show how this is invoked on each of the
+ embedded platforms for a file called \c{qconfig-myfile.h}:
+
+ \bold{Embedded Linux:}
+
+ \snippet doc/src/snippets/code/doc_src_emb-features.qdoc 3
+
+ \bold{Windows CE:}
+
+ \snippet doc/src/snippets/code/doc_src_emb-features.qdoc 2
+
+ Qt provides several ready-made custom configuration files,
+ defining minimal, small, medium and large installations,
+ respectively. These files are located in the
+ \c{/src/corelib/global} directory in the Qt source distribution.
+*/