每个源目录都需要一个CMakeLists.txt。你的结构应该看起来像这样：

root
|-MainProject
| |-inc
| | '-main.h
| |-src
| | |-main.cpp
| | '-CMakeLists.txt
| '-CMakeLists.txt 
|-LibProject
| |-inc
| | '-test.h
| |-src
| | |-test.cpp
| | '-CMakeLists.txt
| '-CMakeLists.txt
'-CMakeLists.txt

root/CMakeLists.txt的内容：

project(MyProject)
add_subdirectory(MainProject)
add_subdirectory(LibProject)

LibProject/CMakeLists.txt和MainProject/CMakeLists.txt的含量：

add_subdirectory(src)

LibProject/src/CMakeLists.txt的内容：

# Notice name prefix of this variable, set by CMake according
# to value given with "project()" in the root CMakeLists.txt.
include_directories(${MyProject_SOURCE_DIR}/LibProject/inc)
add_library(LibProject test.cpp)

MainProject/src/CMakeLists.txt的内容：

include_directories(${MyProject_SOURCE_DIR}/MainProject/inc)
# I assume you want to use LibProject as a library in MainProject.
include_directories(${MyProject_SOURCE_DIR}/LibProject/inc)
link_directories(${MyProject_SOURCE_DIR}/LibProject/src)
add_executable(MainProject main.cpp)
target_link_libraries(MainProject LibProject)

然后使用以下配置和构建：

$ cd root
$ mkdir build
$ cd build
$ cmake ..
$ make

你可以通过以下方式来做到这一点：

• MainProject目录中的CMakeLists.txt：

project(MainProject)

add_subdirectory(LibProject/src)
add_subdirectory(MainProject/src)

• LibProject/src目录中的CMakeLists.txt：

include_directories(${PROJECT_SOURCE_DIR}/LibProject/inc/)
add_library(LibProject test.cpp)

• MainProject/src目录中的CMakeLists.txt：

include_directories(${PROJECT_SOURCE_DIR}/MainProject/inc/)
add_executable(MainProject main.cpp)
target_link_libraries(MainProject LibProject)

在我的例子中，我想用一个单个CMakeList来做。对我很有效。我添加我的解决方案，以防它适用于任何人。
这就是我在我的案例中所做的：

My structure:
Project
|CMakeLists.txt
|-src
| |*.cpp
| |*.c
|-include
| |*.hpp
| |*.h

我的CMakeLists.txt有主要部分：

include_directories(
        ${PROJECT_SOURCE_DIR}/include
        ${PROJECT_SOURCE_DIR}/src
)

^允许.cpp文件在include文件夹中添加头文件。

file(GLOB all_SRCS
        "${PROJECT_SOURCE_DIR}/include/*.h"
        "${PROJECT_SOURCE_DIR}/include/*.hpp"
        "${PROJECT_SOURCE_DIR}/src/*.cpp"
        "${PROJECT_SOURCE_DIR}/src/*.c"
        )

^只要添加这些文件夹中的任何内容即可。

add_executable(MyTarget ${all_SRCS})

^从所有源列表中构建目标
PS：如果你想看到完整的CMakeLists.txt去项目链接NEGU93/ForbiddenDesert .