FindQt4¶
Finding and Using Qt4¶
This module can be used to find Qt4. The most important issue is that
the Qt4 qmake is available via the system path. This qmake is then
used to detect basically everything else. This module defines a
number of IMPORTED targets, macros and variables.
Typical usage could be something like:
set(CMAKE_AUTOMOC ON)
set(CMAKE_INCLUDE_CURRENT_DIR ON)
find_package(Qt4 4.4.3 REQUIRED QtGui QtXml)
add_executable(myexe main.cpp)
target_link_libraries(myexe Qt4::QtGui Qt4::QtXml)
Note
When using IMPORTED targets, the qtmain.lib static library is
automatically linked on Windows for WIN32
executables. To disable that globally, set the
QT4_NO_LINK_QTMAIN variable before finding Qt4. To disable that
for a particular executable, set the QT4_NO_LINK_QTMAIN target
property to TRUE on the executable.
Qt Build Tools¶
Qt relies on some bundled tools for code generation, such as moc for
meta-object code generation,``uic`` for widget layout and population,
and rcc for virtual filesystem content generation. These tools may be
automatically invoked by cmake(1) if the appropriate conditions
are met. See cmake-qt(7) for more.
Qt Macros¶
In some cases it can be necessary or useful to invoke the Qt build tools in a more-manual way. Several macros are available to add targets for such uses.
macro QT4_WRAP_CPP(outfiles inputfile ... [TARGET tgt] OPTIONS ...)
create moc code from a list of files containing Qt class with
the Q_OBJECT declaration. Per-directory preprocessor definitions
are also added. If the <tgt> is specified, the
INTERFACE_INCLUDE_DIRECTORIES and INTERFACE_COMPILE_DEFINITIONS from
the <tgt> are passed to moc. Options may be given to moc, such as
those found when executing "moc -help".
macro QT4_WRAP_UI(outfiles inputfile ... OPTIONS ...)
create code from a list of Qt designer ui files.
Options may be given to uic, such as those found
when executing "uic -help"
macro QT4_ADD_RESOURCES(outfiles inputfile ... OPTIONS ...)
create code from a list of Qt resource files.
Options may be given to rcc, such as those found
when executing "rcc -help"
macro QT4_GENERATE_MOC(inputfile outputfile [TARGET tgt])
creates a rule to run moc on infile and create outfile.
Use this if for some reason QT4_WRAP_CPP() isn't appropriate, e.g.
because you need a custom filename for the moc file or something
similar. If the <tgt> is specified, the
INTERFACE_INCLUDE_DIRECTORIES and INTERFACE_COMPILE_DEFINITIONS from
the <tgt> are passed to moc.
macro QT4_ADD_DBUS_INTERFACE(outfiles interface basename)
Create the interface header and implementation files with the
given basename from the given interface xml file and add it to
the list of sources.
You can pass additional parameters to the qdbusxml2cpp call by setting
properties on the input file:
INCLUDE the given file will be included in the generate interface header
CLASSNAME the generated class is named accordingly
NO_NAMESPACE the generated class is not wrapped in a namespace
macro QT4_ADD_DBUS_INTERFACES(outfiles inputfile ... )
Create the interface header and implementation files
for all listed interface xml files.
The basename will be automatically determined from the name
of the xml file.
The source file properties described for
QT4_ADD_DBUS_INTERFACE also apply here.
macro QT4_ADD_DBUS_ADAPTOR(outfiles xmlfile parentheader parentclassname
[basename] [classname])
create a dbus adaptor (header and implementation file) from the xml file
describing the interface, and add it to the list of sources. The adaptor
forwards the calls to a parent class, defined in parentheader and named
parentclassname. The name of the generated files will be
<basename>adaptor.{cpp,h} where basename defaults to the basename of the
xml file.
If <classname> is provided, then it will be used as the classname of the
adaptor itself.
macro QT4_GENERATE_DBUS_INTERFACE( header [interfacename] OPTIONS ...)
generate the xml interface file from the given header.
If the optional argument interfacename is omitted, the name of the
interface file is constructed from the basename of the header with
the suffix .xml appended.
Options may be given to qdbuscpp2xml, such as those found when
executing "qdbuscpp2xml --help"
macro QT4_CREATE_TRANSLATION( qm_files directories ... sources ...
ts_files ... OPTIONS ...)
out: qm_files
in: directories sources ts_files
options: flags to pass to lupdate, such as -extensions to specify
extensions for a directory scan.
generates commands to create .ts (vie lupdate) and .qm
(via lrelease) - files from directories and/or sources. The ts files are
created and/or updated in the source tree (unless given with full paths).
The qm files are generated in the build tree.
Updating the translations can be done by adding the qm_files
to the source list of your library/executable, so they are
always updated, or by adding a custom target to control when
they get updated/generated.
macro QT4_ADD_TRANSLATION( qm_files ts_files ... )
out: qm_files
in: ts_files
generates commands to create .qm from .ts - files. The generated
filenames can be found in qm_files. The ts_files
must exist and are not updated in any way.
macro QT4_AUTOMOC(sourcefile1 sourcefile2 ... [TARGET tgt])
The qt4_automoc macro is obsolete. Use the CMAKE_AUTOMOC feature instead.
This macro is still experimental.
It can be used to have moc automatically handled.
So if you have the files foo.h and foo.cpp, and in foo.h a
a class uses the Q_OBJECT macro, moc has to run on it. If you don't
want to use QT4_WRAP_CPP() (which is reliable and mature), you can insert
#include "foo.moc"
in foo.cpp and then give foo.cpp as argument to QT4_AUTOMOC(). This will
scan all listed files at cmake-time for such included moc files and if it
finds them cause a rule to be generated to run moc at build time on the
accompanying header file foo.h.
If a source file has the SKIP_AUTOMOC property set it will be ignored by
this macro.
If the <tgt> is specified, the INTERFACE_INCLUDE_DIRECTORIES and
INTERFACE_COMPILE_DEFINITIONS from the <tgt> are passed to moc.
function QT4_USE_MODULES( target [link_type] modules...)
This function is obsolete. Use target_link_libraries with IMPORTED targets
instead.
Make <target> use the <modules> from Qt. Using a Qt module means
to link to the library, add the relevant include directories for the
module, and add the relevant compiler defines for using the module.
Modules are roughly equivalent to components of Qt4, so usage would be
something like:
qt4_use_modules(myexe Core Gui Declarative)
to use QtCore, QtGui and QtDeclarative. The optional <link_type> argument
can be specified as either LINK_PUBLIC or LINK_PRIVATE to specify the
same argument to the target_link_libraries call.
IMPORTED Targets¶
A particular Qt library may be used by using the corresponding
IMPORTED target with the target_link_libraries()
command:
target_link_libraries(myexe Qt4::QtGui Qt4::QtXml)
Using a target in this way causes :cmake(1)` to use the appropriate include
directories and compile definitions for the target when compiling myexe.
Targets are aware of their dependencies, so for example it is not necessary
to list Qt4::QtCore if another Qt library is listed, and it is not
necessary to list Qt4::QtGui if Qt4::QtDeclarative is listed.
Targets may be tested for existence in the usual way with the
if(TARGET) command.
The Qt toolkit may contain both debug and release libraries.
cmake(1) will choose the appropriate version based on the build
configuration.
Qt4::QtCore- The QtCore target
Qt4::QtGui- The QtGui target
Qt4::Qt3Support- The Qt3Support target
Qt4::QtAssistant- The QtAssistant target
Qt4::QtAssistantClient- The QtAssistantClient target
Qt4::QAxContainer- The QAxContainer target (Windows only)
Qt4::QAxServer- The QAxServer target (Windows only)
Qt4::QtDBus- The QtDBus target
Qt4::QtDeclarative- The QtDeclarative target
Qt4::QtDesigner- The QtDesigner target
Qt4::QtDesignerComponents- The QtDesignerComponents target
Qt4::QtHelp- The QtHelp target
Qt4::QtMotif- The QtMotif target
Qt4::QtMultimedia- The QtMultimedia target
Qt4::QtNetwork- The QtNetwork target
Qt4::QtNsPLugin- The QtNsPLugin target
Qt4::QtOpenGL- The QtOpenGL target
Qt4::QtScript- The QtScript target
Qt4::QtScriptTools- The QtScriptTools target
Qt4::QtSql- The QtSql target
Qt4::QtSvg- The QtSvg target
Qt4::QtTest- The QtTest target
Qt4::QtUiTools- The QtUiTools target
Qt4::QtWebKit- The QtWebKit target
Qt4::QtXml- The QtXml target
Qt4::QtXmlPatterns- The QtXmlPatterns target
Qt4::phonon- The phonon target
Result Variables¶
Below is a detailed list of variables that FindQt4.cmake sets.
Qt4_FOUND- If false, don’t try to use Qt 4.
QT_FOUND- If false, don’t try to use Qt. This variable is for compatibility only.
QT4_FOUND- If false, don’t try to use Qt 4. This variable is for compatibility only.
QT_VERSION_MAJOR- The major version of Qt found.
QT_VERSION_MINOR- The minor version of Qt found.
QT_VERSION_PATCH- The patch version of Qt found.