Android Studio Run程序时自动执行自定义task

android {
    compileSdkVersion 19
    buildToolsVersion "25.0.2"

    defaultConfig {
        applicationId "xxxxxxxxxxxxxx"
        minSdkVersion 8
        targetSdkVersion 19
    }

    buildTypes {
        release {
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.txt'
        }
    }

    sourceSets.main {
        jniLibs.srcDir 'libs'
    }

    externalNativeBuild {
        ndkBuild {
            path 'src/main/jni/Android.mk'
        }
    }
    //打包运行app时会自动调用ndkBuild task
    tasks.withType(JavaCompile) {
        compileTask -> compileTask.dependsOn 'ndkBuild'
    }

}

task ndkBuild(type: Exec, description: 'Compile JNI source via NDK') {
    println('executing ndkBuild')
    def ndkBuildingDir = 'C:\\Android\\sdk\\ndk-bundle'
    def ndkBuildPath = ndkBuildingDir
    ndkBuildPath = ndkBuildingDir + '/ndk-build.cmd'
    commandLine ndkBuildPath, '-j8', '-C', file('src/main').absolutePath
}