CMake install to /bin

我在CMake中有一个目录结构，如下所示：

root
    CMakeLists.txt
    subproject_folder
        my_dll_library
        CMakeLists.txt
            src
                source1.cpp
                source2.cpp
            inc
                library.h
            CMakeLists.txt
        library_demo
            src
                demo.cpp
            CMakeLists.txt
    build
    bin

我的根 CmakeLists.txt 包含以下内容：

cmake_minimum_required(VERSION 2.8)
add_subdirectory(subproject_folder)
if(MSVC)
# Force to always compile with W4
    if(CMAKE_CXX_FLAGS MATCHES "/W[0-4]")
            string(REGEX REPLACE "/W[0-4]" "/W4" CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS}")
    else()
            set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} /W4")
endif()
    elseif(CMAKE_COMPILER_IS_GNUCC OR CMAKE_COMPILER_IS_GNUCXX)
    # Update if necessary
        set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wall -Wno-long-long -pedantic")
    endif()
    set(CMAKE_RUNTIME_OUTPUT_DIRECTORY ${PROJECT_SOURCE_DIR}/bin)

子项目文件夹中的 CMakeList 仅包含

add_subdirectory(my_dll_library)
add_subdirectory(library_demo)

library_demo文件夹中的 CMakeList 包含

project(library_demo)
add_executable(librarydemo src/demo.cpp)
target_link_libraries(librarydemo my_dll_library)
install(TARGETS librarydemo DESTINATION bin)

my_dll_library文件夹中的 CMakeList 包含

add_library(lib_zaber SHARED src/source1.cpp src/source2.cpp)
install(TARGETS lib_zaber DESTINATION bin)

我想将演示可执行文件和库 DLL 复制到 bin 文件夹，但它不起作用。我做错了什么？