cmake语法学习入门

一个好的工具环境或许能更容易入门，我选择的是cloin，支持语法提示，高亮。

image.png


#get_filename_component(ANDROID_NDK_EXPECTED_PATH "d:/ahello.c"   ABSOLUTE) #原封不动取目录或包含路径的文件 如果不填写路径会自动 添加上自己项目路径,也就是CMAKE_CURRENT_LIST_DIR和它拼接
#get_filename_component(ANDROID_NDK_EXPECTED_PATH "d:/ahello.c"   NAME) #取文件名,不包含路径
#get_filename_component(ANDROID_NDK_EXPECTED_PATH "d:/ahello.c"   EXT) #取扩展名
#get_filename_component(ANDROID_NDK_EXPECTED_PATH "d:/ahello.c"   REALPATH) #和ABSOLUTE 一样，
#get_filename_component(ANDROID_NDK_EXPECTED_PATH "d:/ahello.c"   PATH) #只保留路径

完整代码

# cmake_minimum_required(VERSION <specify CMake version here>)
message(${BUILD_TYPE})
if (BUILD_TYPE STREQUAL arm)#判断字符串是否等于arm
    #    project(MyApplication)
    cmake_minimum_required(VERSION 3.4.1)
    message("is arm set version 3.12")
    set(CMAKE_C_FLAGS "-std=gnu99")
    set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -fPIE")
    message(${CMAKE_C_FLAGS})
    set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} -fPIE -pie") #设置变量 CMAKE_EXE_LINKER_FLAGS为右边的内容。

    #set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} -fPIE -pie")
    # 配置使用 NDK Standalone Toolchain 编译
    set(NDK_STANDALONE_TOOLCHAIN E:/cross-c/ndk_toolchain)
    set(CMAKE_SYSTEM_NAME AndroidARM)
    set(CMAKE_SYSTEM_VERSION 3)

    set(CMAKE_C_COMPILER ${NDK_STANDALONE_TOOLCHAIN}/bin/arm-linux-androideabi-gcc)
    set(CMAKE_CXX_COMPILER ${NDK_STANDALONE_TOOLCHAIN}/bin/arm-linux-androideabi-g++)

    set(CMAKE_FIND_ROOT_PATH ${NDK_STANDALONE_TOOLCHAIN})

    # 使用 NDK 提供的头文件
    #add_definitions("--sysroot=E:/android_source/android-4.1.1_r1/android-4.1.1_r1/prebuilts/ndk/android-ndk-r7/platforms/android-9/arch-arm")
    add_definitions("--sysroot=${NDK_STANDALONE_TOOLCHAIN}/sysroot")

else ()
    set(CMAKE_LEGACY_CYGWIN_WIN32 0) # Remove when CMake >= 2.8.4 is required
    project(MyApplication)
    set(CMAKE_CXX_STANDARD 11)
    message("window set var")
    message(WARNING "xxxxx")

    message(${CMAKE_CURRENT_LIST_DIR}) #/cygdrive/d/luozheng/cproject/MyApplication 当前目录
endif ()

set(NAME qssq666)
message(${NAME})
if (NAME)
    message("has set var NAME=${NAME}")
    list(APPEND LIST_VAR "--sysroot ${ANDROID_SYSTEM_LIBRARY_PATH} XXX XXX XXX XXX")

    unset(NAME) #只能清空变量
    if (NAME)
        message("name deleted")
    else ()
        message("name delete fail var is ${NAME}")
    endif ()
    message(${LIST_VAR})
else ()
    message("not set var NAME")
endif ()


message("ndk path${ANDROID_NDK}  ANDROID_NDK_EXPECTED_PATH ${ANDROID_NDK_EXPECTED_PATH}")


aux_source_directory(src SOURCE_FILES) #添加一个目录

add_executable(good src/hello.c)


#get_filename_component(ANDROID_NDK_EXPECTED_PATH "d:/ahello.c"   ABSOLUTE) #原封不动取目录或包含路径的文件 如果不填写路径会自动 添加上自己项目路径,也就是CMAKE_CURRENT_LIST_DIR和它拼接
#get_filename_component(ANDROID_NDK_EXPECTED_PATH "d:/ahello.c"   NAME) #取文件名,不包含路径
#get_filename_component(ANDROID_NDK_EXPECTED_PATH "d:/ahello.c"   EXT) #取扩展名
#get_filename_component(ANDROID_NDK_EXPECTED_PATH "d:/ahello.c"   REALPATH) #和ABSOLUTE 一样，
#get_filename_component(ANDROID_NDK_EXPECTED_PATH "d:/ahello.c"   PATH) #只保留路径


#get_filename_component(ANDROID_NDK_EXPECTED_PATH "${CMAKE_CURRENT_LIST_DIR}/../.." ABSOLUTE) #/cygdrive/d/luo zheng 向上取两级
#get_filename_component(ANDROID_NDK_EXPECTED_PATH "${CMAKE_CURRENT_LIST_DIR}/../.." ABSOLUTE)



#add_executable(good src/test12.c)
#add_executable(hello src/hello1.c)
#add_executable(hello main.cpp test1.cpp test1.h)

生成警告信息

image.png

set toolchain=%ANDROID_HOME%/ndk-bundle/build/cmake/android.toolchain.cmake
::set toolchain=%ANDROID_HOME%\cmake\3.6.4111459\android.toolchain.cmake
set android_ndk=%ANDROID_HOME%/ndk-bundle
set build_type=Release
set gernerator="Ninja"
if not exist %1 md %1
cd %1
cmake ../.. -DCMAKE_TOOLCHAIN_FILE=%toolchain% -DANDROID_NDK=%android_ndk% -DCMAKE_BUILD_TYPE=%build_type% -DANDROID_ABI="%1" -DCMAKE_GENERATOR=%gernerator%


ninja

其中-DCMAKE_BUILD_TYPE=是表明创建一个变量CMAKE_BUILD_TYPE
获取当前目录
message(${CMAKE_CURRENT_LIST_DIR})