title: Create an AAR with multiple AARs/JARs
body: <p>I have seen questions (<a href="https://stackoverflow.com/questions/30084314/android-studio-combine-2-aar-into-one">Android Studio combine 2 .aar into one</a> and others) posted by various developers but I haven't seen a definitive response that enables me to create an AAR that includes 1 or more AARs or JARs (I can do with JARs since I don't need to share any resources; only classes). Here is the app.gradle for my library project:</p>
  
  <pre><code>apply plugin: 'com.android.library'
  
  android {
      compileSdkVersion 19
      buildToolsVersion "19.1.0"
  
      defaultConfig {
          minSdkVersion 16
          targetSdkVersion 21
      }
  
      buildTypes {
          release {
              minifyEnabled false
              proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.txt'
          }
      }
  }
  
  dependencies {
      compile 'com.google.code.gson:gson:2.1'
      compile ('libs/eventbus.jar')
      compile project(':core-release')
      compile project(':midware-release')
  }
  </code></pre>
  
  <p>Again, this app is a library project which needs two other library projects ('core-release', 'midware-release') and while I was able to generate one AAR file that I can use in my application, the application was unable to find the dependent library projects' classes so, I had to add the two library projects' AARs into my application.</p>
  
  <p>Here is the app.gradle application project (without adding the JARs manually) which is unable to find the dependent projects' classes:</p>
  
  <pre><code>apply plugin: 'com.android.application'
  
  android {
      compileSdkVersion 23
      buildToolsVersion "23.0.1"
  
      defaultConfig {
          applicationId "com.app.sample"
          minSdkVersion 19
          targetSdkVersion 23
          versionCode 1
          versionName "1.0"
      }
      buildTypes {
          release {
              minifyEnabled false
              proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
          }
      }
  }
  
  dependencies {
      compile fileTree(dir: 'libs', include: ['*.jar'])
      testCompile 'junit:junit:4.12'
      compile 'com.android.support:appcompat-v7:23.1.1'
      compile 'com.android.support:design:23.1.1'
      compile files('libs/eventbus.jar')
      compile project(':sdk3-debug')
  }
  </code></pre>
  
  <p>I don't think the library project's AAR file is pulling in the dependent projects (AAR or JAR) and hence the application is unable to find the classes.</p>
  
  <p>I read about transitive dependency, but I was unable to find an example implementation which may help with my situation.</p>