cmake添加lib库

# 生成lib文件 libhello.a
add_library(hello hello.cxx)

# 在top level添加子目录
add_subdirectory(hello)

# 在顶层添加link依赖
target_link_libraries(Test PUBLIC hello)

# 添加targert依赖的头文件路径
target_include_directories(Test PUBLIC
					"{PROJECT_BINARY_DIR}"
					"{PROJECT_SOURCE_DIR}/hello")

# test.cxx添加头文件
#include "hello.hpp"

接前篇，新增一个hello.hpp和hello.cpp的文件，期望将其打包为libhello.a被Test调用，具体操作：

• 在test.cxx所在目录下创建hello，并在hello下分别创建hello.hpp、hello.cpp

void hello();

#include <iostream>
#include "hello.hpp"
void hello() {
    std::cout << "hello world" << std::endl;
}

• 在hello目录下新建CMakeLists.txt

add_library(hello hello.cxx)

• 在顶层的CMakeLists.txt写入

target_link_libraries(Test PUBLIC hello)
target_include_directories(Test PUBLIC
				"{PROJECT_BINARY_DIR}"
				"{PROJECT_SOURCE_DIR}/hello")

• test.cxx里添加头文件

#include <iostream>
#include <memory>
#include "version.hpp"
#include "hello.hpp"
class A {
public:
    A() { std::cout << "create A" << std::endl; }
    ~A() { std::cout << "destroy A" << std::endl; }
    void show() { std::cout << "call A function" << std::endl; }
};
int main() {
    std::cout << "VERSION:" << TEST_VERSION_MAJOR << "." << TEST_VERSION_MINOR << std::endl;
    std::unique_ptr<A> a = std::make_unique<A>();
    a->show();
    hello();
    return 0;
}

目录结构如下：

├── build
├── CMakeLists.txt
├── hello
│   ├── CMakeLists.txt
│   ├── hello.cpp
│   └── hello.hpp
├── test.cxx
└── version.hpp.in

在build下执行cmake .. && cmake --build .

Test执行结果如下

VERSION:1.0
create A
call A function
hello world
destroy A