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