Qt + CMake开发

Qt添加CMake支持

1、下载CMake并解压

参考https://cmake.org/download/

$ wget https://cmake.org/files/v3.12/cmake-3.12.0-rc3.tar.gz
$ tar xvf cmake-3.12.0-rc3.tar.gz

2、编译并安装CMake

$ cd cmake-3.12.0-rc3/
$ ./bootstrap
$ make -j8
$ sudo make install

3、配置Qt

Qt-->Tools-->Options-->Build & Run-->CMake-->Add

Name：随意，姑且取cmake-3.12.0-rc3

Path：/home/yong/Downloads/cmake-3.12.0-rc3/bin/cmake，即编译出来的CMake命令的绝对路径。

Qt->Tools->Options->Build & Run->Kits->Desktop(dafault)->CMake Tool

创建CMake项目

New Project-->Non-Qt Project-->Plain C++ Application-->...

在选择Build System时，选择CMake

在Kit Selection时选择上面配置的Desktop(dafault)

项目描述如下文件CMakeLists.txt如下：

cmake_minimum_required(VERSION 2.8)
project(cmake-test)

add_library( # Sets the name of the library.
             test_hello
             # Sets the library as a shared library.
             SHARED
             # Provides a relative path to your source file(s).
             ./hello.cpp
             )


add_executable(${PROJECT_NAME} "main.cpp")
target_link_libraries( # Specifies the target library.
                       cmake-test
                       test_hello)

这个文件解释如下：

cmake版本>2.8

项目名称是cmake-test

有两个模块：动态链接库模块test_hello，可执行模块${PROJECT_NAME}=cmake-test

其中cmake-test模块需要动态链接test_hello库

main.cpp如下：

#include <iostream>
#include"hello.h"
#include <stdlib.h>
using namespace std;

int main()
{
    char* result=sayHello("yong");
    cout<<result<<endl;
    free(result);
    return 0;
}

hellp.cpp如下：

#include"hello.h"
#include<iostream>
#include <stdlib.h>
#include<string.h>
using namespace std;
char* sayHello(const char* name){
    string cpp_name=name;
    string result=cpp_name+"-->hello";
    char* c_result=(char*)malloc((result.length()+1)*sizeof(char));
    memcpy(c_result,(const char*)&result[0],result.length()+1);
    return c_result;
}

hello.h如下：

#ifndef HELLO_H
#define HELLO_H

char* sayHello(const char* name);

#endif // HELLO_H

编译项目，运行

1、可以手动编译，例如项目地址是cmake-test

$ tree cmake-test/
cmake-test/
├── CMakeLists.txt
├── CMakeLists.txt.user
├── hello.cpp
├── hello.h
└── main.cpp

0 directories, 5 files

$ cd cmake-test/
$ mkdir build
$ cd build/
$ cmake ..
$ make
Scanning dependencies of target test_hello
[ 25%] Building CXX object CMakeFiles/test_hello.dir/hello.cpp.o
[ 50%] Linking CXX shared library libtest_hello.so
[ 50%] Built target test_hello
Scanning dependencies of target cmake-test
[ 75%] Building CXX object CMakeFiles/cmake-test.dir/main.cpp.o
[100%] Linking CXX executable cmake-test
[100%] Built target cmake-test
$ ls
CMakeCache.txt  cmake_install.cmake  libtest_hello.so
CMakeFiles      cmake-test           Makefile

在cmake-test/build下的cmake-test可执行文件和libtest_hello.so就是我们想要的东西。

2、也可以用Qt编译执行