<meta-data
    android:name="UMENG_CHANNEL"
    android:value="${UMENG_CHANNEL_VALUE}" />

   productFlavors {

      baidu {
        manifestPlaceholders = [UMENG_CHANNEL_VALUE: "baidu"]
      }
      helper91 {
        manifestPlaceholders = [UMENG_CHANNEL_VALUE: "helper91"]
      }
      anzhuo {
        manifestPlaceholders = [UMENG_CHANNEL_VALUE: "anzhuo"]
      }
    }

     productFlavors {

      baidu {
      }
      helper91 {
      }
       anzhuo {

      }
    }
    productFlavors.all {
      flavor -> flavor.manifestPlaceholders = [UMENG_CHANNEL_VALUE: name]
    }

 helper91 {
      manifestPlaceholders = [UMENG_CHANNEL_VALUE: "helper91"]
      applicationId="com.test.channel"
    }

 applicationVariants.all { variant ->
    variant.outputs.each { output ->
      def outputFile = output.outputFile
      if (variant.buildType.name.equals('release')) {
        //生成apk名字的格式：Channel_1.0.0_2016-06-22_baidu.apk
        //可自定义自己想要生成的格式
        def fileName = "Channel_${defaultConfig.versionName}_${releaseTime()}_${variant.productFlavors[0].name}.apk"
        output.outputFile = new File(outputFile.parent, fileName)
      }
    }
  }

 def releaseTime() {
  return new Date().format("yyyy-MM-dd", TimeZone.getTimeZone("UTC"))
  }