最近将公司ndk项目从eclipse迁移到as，为了方便省事，直接使用原有mk文件。参考网络资料，顺利完成迁移工作。现贴出使用自定义mk文件的关键代码，mark以备后面使用。

 buildTypes {
        release {
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.txt'
        }
        sourceSets {
            main {
                jni.srcDirs = []//设置禁止gradle生成Android.mk
                jniLibs.srcDirs = ['src/main/libs']//设置目标的so存放路径
            }
        }
    }
}



tasks.withType(JavaCompile) {
    compileTask -> compileTask.dependsOn ndkBuild
}

//设置编辑的工作目录
task ndkBuild(type: Exec) {
    workingDir file('src/main/jni')
    commandLine getNdkBuildCmd()
}

//设置清理目录
task cleanNative(type: Exec){
    workingDir file('src/main/jni')
    commandLine getNdkBuildCmd(), 'clean'
}

clean.dependsOn cleanNative//执行清理

def getNdkDir() {
    if (System.env.ANDROID_NDK_ROOT != null)
        return System.env.ANDROID_NDK_ROOT
    Properties properties = new Properties()
    properties.load(project.rootProject.file('local.properties').newDataInputStream())
    def ndkDir = properties.getProperty('ndk.dir', null)
    if (ndkDir == null)
        throw new GradleException("NDK location not found. Define location with ndk.dir in the local.properties file or with an ANDROID_NDK_ROOT environment variable.")
    return ndkDir
}

def getNdkBuildCmd() {
    def ndkBuild = getNdkDir() + "/ndk-build"
    ndkBuild += ".cmd"
    return ndkBuild
}