title: how can I add the aidl file to Android studio (from the in-app billing example)
body: <p>I am currently migrating an Eclipse app to Android Studio.
  This app was using the in app billing.</p>
  
  <p>My main problem is to compile the project and the aidl file (I guess you all use <a href="http://stuff.mit.edu:8001/afs/sipb.mit.edu/project/android/sdk/android-sdk-linux/extras/google/play_billing/IInAppBillingService.aidl" rel="noreferrer">this file</a>)</p>
  
  <p>I get this error message: </p>
  
  <pre><code>Gradle: error: cannot find symbol class IInAppBillingService
  Gradle: error: package IInAppBillingService does not exist
  </code></pre>
  
  <p>So, following some tutorials, I move this file from com.mypackage.billing to src/main/aidl
  (see <a href="https://code.google.com/p/android/issues/detail?id=56328" rel="noreferrer">this reference</a>)</p>
  
  <p>But as soon, as I do that, I get this message:</p>
  
  <blockquote>
    <p>Gradle: Execution failed for task ':xxxxxxxxxxx:compileDebugAidl'.</p>
    
    <blockquote>
      <p>Failed to run command:
              (...)     C:\Users\xxxx\AndroidStudioProjects\xxxxxxProject\xxxxxxx\src\main\aidl\IInAppBillingService.aidl:45
      interface IInAppBillingService should be declared in a file called
      com\xxxxxxxx\billing\IInAppBillingService.aidl.</p>
    </blockquote>
  </blockquote>
  
  <p>The message is clearly a contradiction with the post from the Google bug page I linked above.</p>
  
  <p>Anyone suceeded to make this aidl file to work and can help me?</p>
  
  <p><img src="https://i.stack.imgur.com/daRec.png" alt="enter image description here"></p>
  
  <p>Just to inform, some links I followed:</p>
  
  <ul>
  <li><a href="http://tools.android.com/tech-docs/new-build-system/user-guide" rel="noreferrer">http://tools.android.com/tech-docs/new-build-system/user-guide</a></li>
  <li><a href="http://developer.android.com/guide/components/aidl.html" rel="noreferrer">http://developer.android.com/guide/components/aidl.html</a></li>
  </ul>