Gradle 之多环境构建(开发环境，线上环境)

1. 在build.gradle 内添加以下配置：

android {
      ...
    flavorDimensions "default"
    productFlavors {
        //测试站和正式站
        //构建时命令：gradlew assembleOnline  / gradlew assembleDev
        online {
            dimension "default"
            //可以构建不同的包名
            applicationId "com.xxx.xxx"
            resValue "string", "app_name", "xxx"
            buildConfigField "String", "HOST_URL", "\"https://online.xxx.com/\""
            buildConfigField "String", "SECRET", "\"xxxxxxxxxxxxxxx\""
            buildConfigField "String", "APP_ID", "\"xxx\""
            buildConfigField "int", "SOCKET_PORT", "8092"
        }

        dev {
            dimension "default"
            applicationId "com.xxx.xxx"
            resValue "string", "app_name", "xxx-测试站"
            buildConfigField "String", "HOST_URL", "\"https://tester.xxx.com/\""
            buildConfigField "String", "SECRET", "\"xxxxxxxxxxxxxxxxxxxx\""
            buildConfigField "String", "APP_ID", "\"xxx\""
            buildConfigField "int", "SOCKET_PORT", "8093"
        }

    }
}

点击build，可以生成BuildConfig.java文件，gradle定义的变量都会已静态常量的形式展示：

public final class BuildConfig {
  public static final boolean DEBUG = Boolean.parseBoolean("true");
  public static final String APPLICATION_ID = "com.xxx.xxx";
  public static final String BUILD_TYPE = "debug";
  public static final String FLAVOR = "dev";
  public static final int VERSION_CODE = 86;
  public static final String VERSION_NAME = "2.6";
  // Field from product flavor: dev
  public static final String APP_ID = "xxx";
  // Field from product flavor: dev
  public static final String HOST_URL = "https://tester.xxxx.com/";
  // Field from product flavor: dev
  public static final String SECRET = "xxxxxxxxxxxxxxxxxxx";
  // Field from product flavor: dev
  public static final int SOCKET_PORT = 8093;
}

在使用的时候，比如要使用HOST_URL,可以直接使用BuildConfig.HOST_URL

在Build Variants中会生成四种构建类型

image.png

开发时具体使用：
如果需要开发环境，Build Variants选择devDebug，连接手机进行调试。
如果需要调试线上环境，选择onlineDebug

打包：
可以使用命令：
gradlew assembleOnline 可生成线上包。
gradlew assembleDev 可生成测试站的正式包

也可以使用Android Studio右侧的Gradle

如果升级Android Studio后，右侧Gradle没有assemble相关的选项

image.png

出现该问题，是因为升级了android studio到4.2.1，默认关闭了，打开即可

image.png

打开后，重新refresh一下：

image.png

就可以打包了。

参考:

1. android studio的右侧gradle只有dependens，没有tasks任务栏
   https://blog.csdn.net/feijian_/article/details/117573009
2. Android Studio3.0 flavorDimensions多维度理解(版本差异化打包)
   https://blog.csdn.net/chen_xi_hao/article/details/80526049
3. Gradle 之创建 Build Variants
   https://www.jianshu.com/p/6ceb15559e81