我正在使用 Qt 4.6、CMake 2.8 和 Visual Studio 2008 for Windows 平台开发一个大型项目。
就构建系统而言，这都是标准的东西：我使用 CMake 的 QT4_WRAP_CPP 宏从头文件生成 moc 文件，然后将其链接到 add_executable 中的最终可执行文件中代码>命令。一切都按预期进行。
此设置的唯一限制是我无法在 .cpp 文件中使用 Q_OBJECT 定义小部件或助手。这对于小型的、特定于上下文的帮助器类来说非常方便，这些类应该出现在它们使用的地方旁边。
我尝试将整个源文件列表（.h 和 .cpp）传递给 QT4_WRAP_CPP，而不仅仅是头文件，但是这不起作用（链接失败，因为一些与 moc 相关的符号未定义）。
我认为问题在于，对于给定的一对文件 foo.h 和 foo.cpp，QT4_WRAP_CPP 宏将生成相同的 moc文件（moc_foo.cxx）位于同一目录中，显然这意味着第一个文件将被第二个文件覆盖，因此符号将在链接时丢失。
有没有办法解决或解决这个问题？例如，我尝试为表单的 foo.cpp 添加特定规则
QT4_GENERATE_MOC(directory/foo.cpp directory/foo.moc)
，然后添加
#include "foo.moc"
在 foo.cpp 的末尾。我认为这应该可行，但遗憾的是 Visual Studio 只允许每个文件有一个构建规则，并且 .cpp 文件已经有一个构建规则（编译到目标文件），所以这种方法不起作用，至少使用 Visual Studio 是这样。
我的另一个想法是基于 QT4_WRAP_CPP（在 share/cmake-2.8/Modules/Qt4Macros.h 中定义）创建一个新的宏，例如 QT4_WRAP_CPP_WITH_PREFIX。 cmake），这将需要一个额外的前缀参数，并将此前缀添加到生成的 moc 文件中。这样，我将使用不同的前缀调用 QT4_WRAP_CPP_WITH_PREFIX 两次，一次针对 .h 文件，一次针对 .cpp 文件。我只是不喜欢这种方法，因为我会搞乱 CMake 的 Qt 支持的内部结构，而不是使用公共 API。
还有更好的主意吗？
I'm developing a large project using Qt 4.6, CMake 2.8 and Visual Studio 2008 for the Windows platform.
As far the build system goes, it's all standard stuff: I'm using CMake's QT4_WRAP_CPP macro to generate moc files from header files, which are then linked into the final executable in the add_executable command. Everything is working as expected.
The only restriction with this setup is that I can't define widgets or helper using Q_OBJECT in .cpp files. This would be very convenient for small, context-specific helpers classes that should appear right next to where they're used.
I tried to pass the whole list of source files (both .h and .cpp) to QT4_WRAP_CPP, instead of just the header files, but that doesn't work (linking fails because some moc-related symbols are undefined).
I think the problem is that, for a given pair of files foo.h and foo.cpp, the QT4_WRAP_CPP macro will generate the same moc file (moc_foo.cxx) in the same directory, and obviously that means the first file will be overwritten by the second one, and as a result symbols will be missing at link-time.
Is there a way to fix or work around that problem? For instance, I tried to add a specific rule for foo.cpp of the form
QT4_GENERATE_MOC(directory/foo.cpp directory/foo.moc)
and then add
#include "foo.moc"
at the end of foo.cpp. I think this ought to work, but alas Visual Studio only allows one build rule per file, and .cpp files already have a build rule (compilation to object file), so this approach doesn't work, at least with Visual Studio.
Another idea that I had was to create a new macro, say QT4_WRAP_CPP_WITH_PREFIX, based on QT4_WRAP_CPP (which is defined in share/cmake-2.8/Modules/Qt4Macros.cmake), that would take an additional prefix argument and would add this prefix to the generated moc files. That way, I would call QT4_WRAP_CPP_WITH_PREFIX twice, once for .h files and once for .cpp files, with different prefixes. What I just dislike about this approach is that I'd be messing with the internals of CMake's Qt support, instead of using the public API.
Any better idea?
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评论（3）
最近版本的 CMake 有“automoc”，这对我来说就像一个魅力：
http://blogs.kde.org/2011 /11/01/cool-new-stuff-cmake-286-automoc
只需在 CMakeLists.txt 中添加：
然后在 cpp（例如 example.cpp）文件中添加：
（*.moc 必须与 cpp 匹配文件名）。
Recent versions of CMake have "automoc" which worked like a charm for me:
http://blogs.kde.org/2011/11/01/cool-new-stuff-cmake-286-automoc
Simply add in the CMakeLists.txt:
and then in the cpp (e.g. example.cpp) file:
(the *.moc must match the cpp file's name).
参考文档“使用 MOC”(http://doc.qt.nokia.com/4.1/moc.html)，您只需在实现文件末尾导入“foo.moc”即可。由于您无法相应地调整构建规则，请尝试导出 .pro 文件并按照诺基亚文档的建议应用构建规则。
Referring to the documentation "Using the MOC" (http://doc.qt.nokia.com/4.1/moc.html), you'd only need to import "foo.moc" at the end of your implementation file. As you can not tweak the build rules correspondingly, try to export a .pro file and apply the build rule as suggested by the nokia document.
扩展@DavidDoria，因为我无法对他的回复发表评论：最近版本的 CMake 稍微改变了语法（参见 此处):
#include.cpp>; // 或 #include "moc_.cpp" Extending on @DavidDoria, since I cannot make a comment to his response: Recent versions of CMake have changed the syntax slightly (see here):
#include <moc_<header_base>.cpp> // or #include "moc_<header_base>.cpp"