| AUTOMOC |
| ------- |
| |
| Should the target be processed with auto-moc (for Qt projects). |
| |
| :prop_tgt:`AUTOMOC` is a boolean specifying whether CMake will handle the Qt |
| ``moc`` preprocessor automatically, i.e. without having to use commands like |
| :module:`QT4_WRAP_CPP() <FindQt4>`, ``QT5_WRAP_CPP()``, etc. |
| Currently, Qt versions 4 to 6 are supported. |
| |
| This property is initialized by the value of the :variable:`CMAKE_AUTOMOC` |
| variable if it is set when a target is created. |
| |
| When this property is set ``ON``, CMake will scan the header and |
| source files at build time and invoke ``moc`` accordingly. |
| |
| |
| Header file processing |
| ^^^^^^^^^^^^^^^^^^^^^^ |
| |
| At configuration time, a list of header files that should be scanned by |
| :prop_tgt:`AUTOMOC` is computed from the target's sources. |
| |
| - All header files in the target's sources are added to the scan list. |
| - For all C++ source files ``<source_base>.<source_extension>`` in the |
| target's sources, CMake searches for |
| |
| - a regular header with the same base name |
| (``<source_base>.<header_extention>``) and |
| - a private header with the same base name and a ``_p`` suffix |
| (``<source_base>_p.<header_extention>``) |
| |
| and adds these to the scan list. |
| |
| At build time, CMake scans each unknown or modified header file from the |
| list and searches for |
| |
| - a Qt macro from :prop_tgt:`AUTOMOC_MACRO_NAMES`, |
| - additional file dependencies from the ``FILE`` argument of a |
| ``Q_PLUGIN_METADATA`` macro and |
| - additional file dependencies detected by filters defined in |
| :prop_tgt:`AUTOMOC_DEPEND_FILTERS`. |
| |
| If a Qt macro is found, then the header will be compiled by the ``moc`` to the |
| output file ``moc_<base_name>.cpp``. The complete output file path is |
| described in the section `Output file location`_. |
| |
| The header will be ``moc`` compiled again if a file from the additional file |
| dependencies changes. |
| |
| Header ``moc`` output files ``moc_<base_name>.cpp`` can be included in source |
| files. In the section `Including header moc files in sources`_ there is more |
| information on that topic. |
| |
| |
| Source file processing |
| ^^^^^^^^^^^^^^^^^^^^^^ |
| |
| At build time, CMake scans each unknown or modified C++ source file from the |
| target's sources for |
| |
| - a Qt macro from :prop_tgt:`AUTOMOC_MACRO_NAMES`, |
| - includes of header ``moc`` files |
| (see `Including header moc files in sources`_), |
| - additional file dependencies from the ``FILE`` argument of a |
| ``Q_PLUGIN_METADATA`` macro and |
| - additional file dependencies detected by filters defined in |
| :prop_tgt:`AUTOMOC_DEPEND_FILTERS`. |
| |
| If a Qt macro is found, then the C++ source file |
| ``<base>.<source_extension>`` is expected to as well contain an include |
| statement |
| |
| .. code-block:: c++ |
| |
| #include <<base>.moc> // or |
| #include "<base>.moc" |
| |
| The source file then will be compiled by the ``moc`` to the output file |
| ``<base>.moc``. A description of the complete output file path is in section |
| `Output file location`_. |
| |
| The source will be ``moc`` compiled again if a file from the additional file |
| dependencies changes. |
| |
| Including header moc files in sources |
| """"""""""""""""""""""""""""""""""""" |
| |
| A source file can include the ``moc`` output file of a header |
| ``<header_base>.<header_extension>`` by using an include statement of |
| the form |
| |
| .. code-block:: c++ |
| |
| #include <moc_<header_base>.cpp> // or |
| #include "moc_<header_base>.cpp" |
| |
| If the ``moc`` output file of a header is included by a source, it will |
| be generated in a different location than if it was not included. This is |
| described in the section `Output file location`_. |
| |
| |
| Output file location |
| ^^^^^^^^^^^^^^^^^^^^ |
| |
| Included moc output files |
| """"""""""""""""""""""""" |
| |
| ``moc`` output files that are included by a source file will be generated in |
| |
| - ``<AUTOGEN_BUILD_DIR>/include`` |
| for single configuration generators or in |
| - ``<AUTOGEN_BUILD_DIR>/include_<CONFIG>`` |
| for :prop_gbl:`multi configuration <GENERATOR_IS_MULTI_CONFIG>` generators. |
| |
| Where ``<AUTOGEN_BUILD_DIR>`` is the value of the target property |
| :prop_tgt:`AUTOGEN_BUILD_DIR`. |
| |
| The include directory is automatically added to the target's |
| :prop_tgt:`INCLUDE_DIRECTORIES`. |
| |
| Not included moc output files |
| """"""""""""""""""""""""""""" |
| |
| ``moc`` output files that are not included in a source file will be generated |
| in |
| |
| - ``<AUTOGEN_BUILD_DIR>/<SOURCE_DIR_CHECKSUM>`` |
| for single configuration generators or in, |
| - ``<AUTOGEN_BUILD_DIR>/include_<CONFIG>/<SOURCE_DIR_CHECKSUM>`` |
| for :prop_gbl:`multi configuration <GENERATOR_IS_MULTI_CONFIG>` generators. |
| |
| Where ``<SOURCE_DIR_CHECKSUM>`` is a checksum computed from the relative |
| parent directory path of the ``moc`` input file. This scheme allows to have |
| ``moc`` input files with the same name in different directories. |
| |
| All not included ``moc`` output files will be included automatically by the |
| CMake generated file |
| |
| - ``<AUTOGEN_BUILD_DIR>/mocs_compilation.cpp``, or |
| - ``<AUTOGEN_BUILD_DIR>/mocs_compilation_$<CONFIG>.cpp``, |
| |
| which is added to the target's sources. |
| |
| |
| Qt version detection |
| ^^^^^^^^^^^^^^^^^^^^ |
| |
| :prop_tgt:`AUTOMOC` enabled targets need to know the Qt major and minor |
| version they're working with. The major version usually is provided by the |
| ``INTERFACE_QT_MAJOR_VERSION`` property of the ``Qt[456]Core`` library, |
| that the target links to. To find the minor version, CMake builds a list of |
| available Qt versions from |
| |
| - ``Qt6Core_VERSION_MAJOR`` and ``Qt6Core_VERSION_MINOR`` variables |
| (usually set by ``find_package(Qt6...)``) |
| - ``Qt6Core_VERSION_MAJOR`` and ``Qt6Core_VERSION_MINOR`` directory properties |
| - ``Qt5Core_VERSION_MAJOR`` and ``Qt5Core_VERSION_MINOR`` variables |
| (usually set by ``find_package(Qt5...)``) |
| - ``Qt5Core_VERSION_MAJOR`` and ``Qt5Core_VERSION_MINOR`` directory properties |
| - ``QT_VERSION_MAJOR`` and ``QT_VERSION_MINOR`` variables |
| (usually set by ``find_package(Qt4...)``) |
| - ``QT_VERSION_MAJOR`` and ``QT_VERSION_MINOR`` directory properties |
| |
| in the context of the :command:`add_executable` or :command:`add_library` call. |
| |
| Assumed ``INTERFACE_QT_MAJOR_VERSION`` is a valid number, the first |
| entry in the list with a matching major version is taken. If no matching major |
| version was found, an error is generated. |
| If ``INTERFACE_QT_MAJOR_VERSION`` is not a valid number, the first |
| entry in the list is taken. |
| |
| A ``find_package(Qt[456]...)`` call sets the ``QT/Qt[56]Core_VERSION_MAJOR/MINOR`` |
| variables. If the call is in a different context than the |
| :command:`add_executable` or :command:`add_library` call, e.g. in a function, |
| then the version variables might not be available to the :prop_tgt:`AUTOMOC` |
| enabled target. |
| In that case the version variables can be forwarded from the |
| ``find_package(Qt[456]...)`` calling context to the :command:`add_executable` |
| or :command:`add_library` calling context as directory properties. |
| The following Qt5 example demonstrates the procedure. |
| |
| .. code-block:: cmake |
| |
| function (add_qt5_client) |
| find_package(Qt5 REQUIRED QUIET COMPONENTS Core Widgets) |
| ... |
| set_property(DIRECTORY "${CMAKE_CURRENT_SOURCE_DIR}" |
| PROPERTY Qt5Core_VERSION_MAJOR "${Qt5Core_VERSION_MAJOR}") |
| set_property(DIRECTORY "${CMAKE_CURRENT_SOURCE_DIR}" |
| PROPERTY Qt5Core_VERSION_MINOR "${Qt5Core_VERSION_MAJOR}") |
| ... |
| endfunction () |
| ... |
| add_qt5_client() |
| add_executable(myTarget main.cpp) |
| target_link_libraries(myTarget Qt5::QtWidgets) |
| set_property(TARGET myTarget PROPERTY AUTOMOC ON) |
| |
| |
| Modifiers |
| ^^^^^^^^^ |
| |
| :prop_tgt:`AUTOMOC_EXECUTABLE`: |
| The ``moc`` executable will be detected automatically, but can be forced to |
| a certain binary using this target property. |
| |
| :prop_tgt:`AUTOMOC_MOC_OPTIONS`: |
| Additional command line options for ``moc`` can be set in this target property. |
| |
| :prop_tgt:`AUTOMOC_MACRO_NAMES`: |
| This list of Qt macro names can be extended to search for additional macros in |
| headers and sources. |
| |
| :prop_tgt:`AUTOMOC_DEPEND_FILTERS`: |
| ``moc`` dependency file names can be extracted from headers or sources by |
| defining file name filters in this target property. |
| |
| :prop_tgt:`AUTOMOC_COMPILER_PREDEFINES`: |
| Compiler pre definitions for ``moc`` are written to the ``moc_predefs.h`` file. |
| The generation of this file can be enabled or disabled in this target property. |
| |
| :prop_sf:`SKIP_AUTOMOC`: |
| Sources and headers can be excluded from :prop_tgt:`AUTOMOC` processing by |
| setting this source file property. |
| |
| :prop_sf:`SKIP_AUTOGEN`: |
| Source files can be excluded from :prop_tgt:`AUTOMOC`, |
| :prop_tgt:`AUTOUIC` and :prop_tgt:`AUTORCC` processing by |
| setting this source file property. |
| |
| :prop_gbl:`AUTOGEN_SOURCE_GROUP`: |
| This global property can be used to group files generated by |
| :prop_tgt:`AUTOMOC` or :prop_tgt:`AUTORCC` together in an IDE, e.g. in MSVS. |
| |
| :prop_gbl:`AUTOGEN_TARGETS_FOLDER`: |
| This global property can be used to group :prop_tgt:`AUTOMOC`, |
| :prop_tgt:`AUTOUIC` and :prop_tgt:`AUTORCC` targets together in an IDE, |
| e.g. in MSVS. |
| |
| :variable:`CMAKE_GLOBAL_AUTOGEN_TARGET`: |
| A global ``autogen`` target, that depends on all :prop_tgt:`AUTOMOC` or |
| :prop_tgt:`AUTOUIC` generated ``<ORIGIN>_autogen`` targets in the project, |
| will be generated when this variable is ``ON``. |
| |
| :prop_tgt:`AUTOGEN_PARALLEL`: |
| This target property controls the number of ``moc`` or ``uic`` processes to |
| start in parallel during builds. |
| |
| See the :manual:`cmake-qt(7)` manual for more information on using CMake |
| with Qt. |