How to import a library project in Android Studio?

In this short tutorial I would show you how to import a library project in Android Studio v1.2.1.1. The steps to do so are:

1. Goto File -> New -> Import Module.
2. Source Directory -> Browse the project path.
3. Specify the Module Name – it is used for internal project reference.
4. Let Android Studio build the project.
5. Open build.gradle (Module:app) file.
6. Add the following line with your module name in place of “Volley” in the dependencies block:
   
   
   

   1	compile project(':Volley')

7. It should look something like this:
8. After this Android Studio would start saying “gradle files have changed since last project sync”, press the “sync now” link to start a sync.
9. That’s all you need to do.

reference of 

http://www.truiton.com/2015/02/android-studio-add-library-project/