需求

现在有一个第三方库libstatic_add.a和对应的头文件static.h，要求封装一个Module，该Module依赖这个静态库，要求打包的Module包含该静态库。

方案

创建Android Studio Library  Project

创建Project时，记得添加"Include C++ Support"，如果没有安装CMake，LLDB和NDK的话，记得安装一下。

项目创建好后，包括以下目录和文件(部分目录或文件是后面添加的)：

build.gradle配置

针对app模块的build.gradle进行如下配置：

//改为library

apply plugin: ‘com.android.library‘

//读取local.properties里的配置属性add_static_lib.dir，该属性指明libstatic_add.a静态库所在目录

Properties properties = new Properties()

properties.load(project.rootProject.file(‘local.properties‘).newDataInputStream())

def add_static_lib = properties.getProperty(‘add_static_lib.dir‘)

android {

compileSdkVersion 27

defaultConfig {

minSdkVersion 16

targetSdkVersion 27

versionCode 1

versionName "1.0"

testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"

//添加下面

ndk {

abiFilters ‘armeabi-v7a‘

// these platforms cover 99% percent of all Android devices

}

externalNativeBuild {

cmake {

//添加下面

arguments ‘-DANDROID_PLATFORM=android-14‘,

‘-DANDROID_TOOLCHAIN=clang‘,

‘-DANDROID_ARM_NEON=TRUE‘,

‘-DANDROID_STL=gnustl_static‘,

"-DPATH_TO_ADD_STATIC_LIB:STRING=${add_static_lib}"

cFlags ‘-O3‘, ‘-fsigned-char‘ // full optimization, char data type is signed

cppFlags ‘-fsigned-char‘, "-I${add_static_lib}"

}

}

}

//添加下面

sourceSets {

main {

jniLibs.srcDirs = [‘src/main/cpp‘]

}

}

//添加下面

externalNativeBuild {

cmake {

path ‘src/main/cpp/CMakeLists.txt‘

}

}

//添加下面

sourceSets.main {

jni.srcDirs = []

jniLibs.srcDir ‘src/main/libs‘

}

buildTypes {

release {

minifyEnabled false

proguardFiles getDefaultProguardFile(‘proguard-android.txt‘), ‘proguard-rules.pro‘

}

}

}

dependencies {

implementation fileTree(dir: ‘libs‘, include: [‘*.jar‘])

implementation ‘com.android.support:appcompat-v7:27.1.1‘

implementation ‘com.android.support.constraint:constraint-layout:1.1.0‘

implementation ‘com.android.support:design:27.1.1‘

testImplementation ‘junit:junit:4.12‘

androidTestImplementation ‘com.android.support.test:runner:1.0.2‘

androidTestImplementation ‘com.android.support.test.espresso:espresso-core:3.0.2‘

}

local.properties配置

针对app模块的local.propertise进行如下配置：

## This file must *NOT* be checked into Version Control Systems,

# as it contains information specific to your local configuration.

#

# Location of the SDK. This is only used by Gradle.

# For customization when using a Version Control System, please read the

# header note.

#Wed May 16 13:05:05 CST 2018

ndk.dir=D\:\\NanRi\\Android\\android-ndk-r16b

sdk.dir=C\:\\Users\\suning\\AppData\\Local\\Android\\Sdk

//添加如下，指明libstatic_add.a静态库所在目录

add_static_lib.dir=D\:\\NanRi\\Android\\Android-Studio-Project\\ModuleProject\\app\\src\\main\\libs\\

CMakeLists.txt配置

针对app模块下的src\main\cpp\CMakeLists.txt配置如下：

cmake_minimum_required(VERSION 3.4.1)

set(

PATH_TO_ADD_STATIC_LIB

CACHE STRING ""

)

message(${ANDROID_ABI})

file(GLOB CPP_FILES "*.cpp")

add_library(

native-lib

SHARED

${CPP_FILES}

)

include_directories(src/main/cpp)

include_directories(${PATH_TO_ADD_STATIC_LIB})

target_link_libraries(

native-lib

android

OpenSLES

${PATH_TO_ADD_STATIC_LIB}/libstatic_add.a

)

导出AAR

导出的AAR所在路径为“app\build\outputs\aar\app-debug.aar”

可以将app-debug.aar改为app-debug.zip，使用压缩工具打开，可以看到如下：

打开jni文件夹，可以看到里面包含了一个armeabi-v7a文件夹，该文件夹包含了libnative-lib.so库