CMake install dependencies - cmake

Question

I currently want to create an installer with cmake, but don't add all necessary DLLs by myself to CMakeLists.txt. So one solution should be to use fixup_bundle, like here suggested, so hopefully he copy all DLLs, which he can detect with a dependency walker and are on path.
But currently I have no idea how is best way to use it on a target, following code won't work, because he don't resolve TARGET_FILE_DIR like if you are using add_custom_command. Do read location via get_property won't work too, because he don't know the target anymore at time of execution. Any idea?
INSTALL(CODE "
include(BundleUtilities)
fixup_bundle($<TARGET_FILE_DIR:${PROJECT_NAME}> \"\" \"D:\\Qt\")
" COMPONENT Runtime
)

Answer 1

If you are using Qt4, rather than using BundleUtilities directly, you may be better off using the DeployQt4 module. It includes the following three commands which may do what you need:
install_qt4_plugin_path
install_qt4_plugin
install_qt4_executable
If you are using Qt5, it gets a bit trickier. If you are only interested in Windows and/or Mac, then Qt itself provides an appropriate tool for handling/bringing across Qt's dependencies. The relevant tools are called windeployqt and macdeployqt respectively. Sadly, at time of writing, there is no linuxdeployqt tool yet that I'm aware of.
If neither of the above options are open to you or don't do what you need, then at least the DeployQt4 module gives some clues as to how you may be able to use the INSTALL(...) command like you attempted to. The DeployQt4 module uses the following for defining its target (see right near the end of the DeployQt4.cmake file):
FIXUP_QT4_EXECUTABLE(\"\$ENV{DESTDIR}\${CMAKE_INSTALL_PREFIX}/${executable}\" \"\" \"${libs}\" \"${dirs}\" \"${plugins_dir}\" \"${request_qt_conf}\")"
${component}
)
The stuff in front of ${executable} is probably the bit you were missing. In your case, without seeing your full CMakeLists.txt file, I can only assume that you have a single target and it has the same name as your project (since you used ${PROJECT_NAME} in your attempted generator expression). You could try something like the following (not tested):
INSTALL(CODE "
include(BundleUtilities)
fixup_bundle(\"\$ENV{DESTDIR}\${CMAKE_INSTALL_PREFIX}/${MyTarget}\" \"\" \"D:\\Qt\")
" COMPONENT Runtime
)
where MyTarget is the name of the executable for your target (I think without any .exe suffix if you are on Windows). The DESTDIR part is needed when making packages, since CMake will redirect the install location by setting the DESTDIR environment variable (at least with some CMake generators). The CMAKE_INSTALL_PREFIX part is the path under which the application would be installed. There is some history behind this, but the above reflects the correct way of how to refer to the installed executable.