问题
Reading Google instructions, I found that I have to import and reference the Play Service library into the project.
So I created a project, copied google-play-service_lib project, imported it as a library project, went to the main project and added this library as a Module dependency. However, I still have an error that IntelliJ IDEA does not recognize package com.amazon.device.ads.*.
So I had to add a library dependency as well, although this library already exists in the /lib directory of Play Service library project.
Am I doing something wrong or we're actually requested to add both dependencies in IntelliJ IDEA? If yes, is this maybe a bug in IntelliJ IDEA 13? I can't remember of having to do the same in earlier versions of IntelliJ IDEA (I have been using it for three years).
This is how it looks in the end and it works only this way! Check the last two dependencies.
来源：https://stackoverflow.com/questions/22985290/why-does-intellij-idea-13-require-both-lib-project-and-lib-itself-google-play-s