解决maven管理Android项目时pom报错Unknown packaging: apk

增加如下的Maven配置：

<plugin>
<groupId>com.jayway.maven.plugins.android.generation2</groupId>
<artifactId>android-maven-plugin</artifactId>
<version>3.9.0-rc.2</version>
<extensions>true</extensions>
<configuration>
<sdk>
<platform>${android.platform}</platform>
</sdk>
</configuration>
</plugin>