android.applicationVariants.all{ variant ->
    delete "${buildDir}/intermediates/merged_assets/${variant.dirName}"  // buildDir是app下的build目录
    variant.mergeAssets.doLast{
        def sourceDir = "${buildDir}/../"   // 资源存放目录，这里是app下
        print "${buildDir} \n"  // 打印路径
        copy { // 将from目录下的资源拷贝到into 下目录去
            from "${sourceDir}/fromDir"
            into "${outputDir}/res"
        }
    }
}