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** Copyright (C) 2020 The Qt Company Ltd
** Copyright (C) 2012 Klarälvdalens Datakonsult AB, a KDAB Group company, info@kdab.com, author Stephen Kelly <stephen.kelly@kdab.com>
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/*!
\page cmake-manual.html
\target CMake Manual
\title Build with CMake
\brief Describes how to use CMake in your development projects.
\nextpage Get started with CMake
\c{CMake} is a tool to simplify the build process for development projects across different
platforms. \c CMake automatically generates build systems, such as Makefiles and Visual Studio
project files.
\c{CMake} is a 3rd party tool with its own \l{CMake Documentation}{documentation}. This topic
describes how to use \c{CMake} 3.1.0 with Qt 5.
\section1 Table of Contents
\list
\li \l{Get started with CMake}
\list
\li \l{Build a GUI executable}
\li \l{Imported library targets}
\endlist
\li \l{CMake Variable Reference}
\list
\li \l{Module variables}
\li \l{Installation variables}
\endlist
\li \l{CMake Command Reference}
\list
\li \l{Qt5::Core}
\li \l{Qt5::Widgets}
\li \l{Qt5::DBus}
\li \l{Qt5::LinguistTools}
\endlist
\endlist
*/
/*!
\page cmake-get-started.html
\title Get started with CMake
\previouspage Build with CMake
\nextpage CMake Variable Reference
Start with \c{find_package} to locate the libraries and header files shipped with Qt. Then, you
can use these libraries and header files with the \c{target_link_libraries} command to build
Qt-based libraries and applications. This command automatically adds the appropriate include
directories, compile definitions, the position-independent-code flag, and links to the
\c qtmain.lib library on Windows, for example.
\section2 Build a GUI executable
To build a helloworld GUI executable, you need the following:
\snippet snippets/cmake/examples.cmake 0
For \c{find_package} to be successful, \c CMake must find the Qt installation in one of the
following ways:
\list 1
\li Set your \c CMAKE_PREFIX_PATH environment variable to the Qt 5 installation prefix.
This is the recommended way.
\li Set the \c{Qt5_DIR} in the \c CMake cache to the location of the \c{Qt5Config.cmake}
file.
\endlist
The \c CMAKE_AUTOMOC setting runs moc automatically when required. For more details, see
\l{CMake AUTOMOC documentation}.
\section2 Imported library targets
Each Qt module that is loaded defines a CMake library target. The target names
start with \c{Qt5::}, followed by the module name. For example: \c{Qt5::Core}, \c{Qt5::Gui}.
Pass the name of the library target to \c target_link_libraries to use the respective library.
\note Since Qt 5.15, the CMake targets are also available as \c Qt::Core, \c Qt::Gui, and so on.
This eases writing CMake code that can work with both Qt 5 and Qt 6.
Imported targets are created with the same configurations as when Qt was configured. That is:
\list
\li If Qt was configured with the \c -debug switch, an imported target with the DEBUG
configuration is created.
\li If Qt was configured with the \c -release switch, an imported target with the RELEASE
configuration is created.
\li If Qt was configured with the \c -debug-and-release switch, then imported targets are
created with both RELEASE and DEBUG configurations.
\endlist
If your project has custom \c{CMake} build configurations, you have to map your custom
configuration to either the debug or the release Qt configuration.
\snippet snippets/cmake/examples.cmake 2
*/
/*!
\page cmake-variable-reference.html
\title CMake Variable Reference
\brief Provides a complete reference for CMake variables implemented in Qt.
\nextpage CMake Command Reference
\previouspage Build with CMake
\section1 Module variables
Qt modules loaded with \c{find_package} set various variables.
\note You rarely need to access these variables directly. Common tasks like linking against a
module should be done through the library targets each module defines.
For example, \c{find_package(Qt5 COMPONENTS Widgets)}, when successful, makes the following
variables available:
\table
\header
\li Variable
\li Description
\row
\li \c Qt5Widgets_COMPILE_DEFINITIONS
\li A list of compile definitions to use when building against the library.
\row
\li \c Qt5Widgets_DEFINITIONS
\li A list of definitions to use when building against the library.
\row
\li \c Qt5Widgets_EXECUTABLE_COMPILE_FLAGS
\li A string of flags to use when building executables against the library.
\row
\li \c Qt5Widgets_FOUND
\li A boolean that describes whether the module was found successfully.
\row
\li \c Qt5Widgets_INCLUDE_DIRS
\li A list of include directories to use when building against the library.
\row
\li \c Qt5Widgets_LIBRARIES
\li The name of the imported target for the module: \c Qt5::Widgets
\row
\li \c Qt5Widgets_PRIVATE_INCLUDE_DIRS
\li A list of private include directories to use when building against the library
and using private Qt API.
\row
\li \c Qt5Widgets_VERSION_STRING
\li A string containing the module's version.
\endtable
For all packages found with \c{find_package}, equivalents of these variables are available;
they are case-sensitive.
\section1 Installation variables
Additionally, there are also variables that don't relate to a particular package, but to the
Qt installation itself.
\table
\header
\li Variable
\li Description
\row
\li \c QT_DEFAULT_MAJOR_VERSION
\li An integer that controls the Qt version that \c qt_ commands forward to in case of
mixed Qt 5 and Qt 6 projects. It needs to be set to either \c 5 or \c 6 before the
respective \c find_package() calls.
If set to \c 5, commands starting with \c qt_ will call their counterpart starting
with \c qt5_. If set to \c 6, they will call their counterpart starting with
\c qt6_.
If not set, the first \c find_package call defines the default version.
This functionality was added in Qt 5.15.
\row
\li \c QT_LIBINFIX
\li A string that holds the infix used in library names, when Qt is configured with
\c{-libinfix}.
\row
\li \c QT_NO_CREATE_VERSIONLESS_FUNCTIONS
\li Since Qt 5.15, modules define not only commands that start with \c{qt5_},
but also ones with \c{qt_}. You can set \c QT_NO_CREATE_VERSIONLESS_FUNCTIONS
before \c{find_package} to prevent this.
\row
\li \c QT_NO_CREATE_VERSIONLESS_TARGETS
\li Since Qt 5.15, modules define not only targets that start with \c{Qt5::},
but also ones with \c{Qt::}. You can set \c QT_NO_CREATE_VERSIONLESS_TARGETS before
\c{find_package} to prevent this.
\row
\li \c QT_VISIBILITY_AVAILABLE
\li On Unix, a boolean that describes whether Qt libraries and plugins were compiled
with \c{-fvisibility=hidden}. This means that only selected symbols are exported.
\endtable
*/
/*!
\page cmake-command-reference.html
\title CMake Command Reference
\brief Provides a complete reference for CMake commands implemented in Qt.
\previouspage CMake Variable Reference
\section2 Qt5::Core
\annotatedlist cmake-macros-qtcore
\section2 Qt5::DBus
\annotatedlist cmake-commands-qtdbus
\section2 Qt5::LinguistTools
\annotatedlist cmake-macros-qtlinguisttools
\section2 Qt5::RemoteObjects
\annotatedlist cmake-macros-qtremoteobjects
\section2 Qt5::Widgets
\annotatedlist cmake-macros-qtwidgets
*/