FindQt4

查找和使用 Qt4

此模块可以用于查找 Qt4。最重要的问题是 Qt4 的 qmake 可以通过系统路径访问。然后，此 qmake 用于检测基本上所有其他内容。此模块定义了许多 IMPORTED 目标、宏和变量。

典型的用法可能如下所示

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)

注意

当使用 IMPORTED 目标时，对于 WIN32 可执行文件，qtmain.lib 静态库在 Windows 上会自动链接。要全局禁用它，请在查找 Qt4 之前设置 QT4_NO_LINK_QTMAIN 变量。要为特定可执行文件禁用它，请在可执行文件上将 QT4_NO_LINK_QTMAIN 目标属性设置为 TRUE。

Qt 构建工具

Qt 依赖于一些捆绑的工具用于代码生成，例如 moc 用于元对象代码生成，uic 用于窗口部件布局和填充，以及 rcc 用于虚拟文件系统内容生成。如果满足适当的条件，这些工具可能会被 cmake(1) 自动调用。有关更多信息，请参阅 cmake-qt(7)。

Qt 宏

在某些情况下，可能有必要或有用于以更手动的方式调用 Qt 构建工具。有几个宏可用于为此类用途添加目标。

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 (via 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.

导入目标

可以通过使用相应的 IMPORTED 目标和 target_link_libraries() 命令来使用特定的 Qt 库

target_link_libraries(myexe Qt4::QtGui Qt4::QtXml)

以这种方式使用目标会导致 :cmake(1)` 在编译 myexe 时使用目标的适当的包含目录和编译定义。

目标知道它们的依赖关系，因此例如，如果列出了另一个 Qt 库，则不必列出 Qt4::QtCore，如果列出了 Qt4::QtDeclarative，则不必列出 Qt4::QtGui。可以使用 if(TARGET) 命令以通常的方式测试目标是否存在。

Qt 工具包可能包含调试和发布库。cmake(1) 将根据构建配置选择适当的版本。

Qt4::QtCore

QtCore 目标

Qt4::QtGui

QtGui 目标

Qt4::Qt3Support

Qt3Support 目标

Qt4::QtAssistant

QtAssistant 目标

Qt4::QtAssistantClient

QtAssistantClient 目标

Qt4::QAxContainer

QAxContainer 目标 (仅限 Windows)

Qt4::QAxServer

QAxServer 目标 (仅限 Windows)

Qt4::QtDBus

QtDBus 目标

Qt4::QtDeclarative

QtDeclarative 目标

Qt4::QtDesigner

QtDesigner 目标

Qt4::QtDesignerComponents

QtDesignerComponents 目标

Qt4::QtHelp

QtHelp 目标

Qt4::QtMotif

QtMotif 目标

Qt4::QtMultimedia

QtMultimedia 目标

Qt4::QtNetwork

QtNetwork 目标

Qt4::QtNsPLugin

QtNsPLugin 目标

Qt4::QtOpenGL

QtOpenGL 目标

Qt4::QtScript

QtScript 目标

Qt4::QtScriptTools

QtScriptTools 目标

Qt4::QtSql

QtSql 目标

Qt4::QtSvg

QtSvg 目标

Qt4::QtTest

QtTest 目标

Qt4::QtUiTools

QtUiTools 目标

Qt4::QtWebKit

QtWebKit 目标

Qt4::QtXml

QtXml 目标

Qt4::QtXmlPatterns

QtXmlPatterns 目标

Qt4::phonon

phonon 目标

结果变量

以下是 FindQt4.cmake 设置的变量的详细列表。

Qt4_FOUND

如果为 false，则不要尝试使用 Qt 4。

QT_FOUND

如果为 false，则不要尝试使用 Qt。此变量仅用于兼容性。

QT4_FOUND

如果为 false，则不要尝试使用 Qt 4。此变量仅用于兼容性。

QT_VERSION_MAJOR

找到的 Qt 的主版本。

QT_VERSION_MINOR

找到的 Qt 的次版本。

QT_VERSION_PATCH

找到的 Qt 的补丁版本。