如何将项目模块库暴露给 App 模块（Android Studio）

Question

At first, I am using a single module app for the the Android Application, but now I want to separate the module into app module (core-business logic and UI) and libraries module (HTTP-related and base abstract classes).

I made new libraries module as the library module and start moving some utility code from app to libraries but problem comes. The problem is, I want my app to use the dependency used in libraries module without having to include same dependency in both build.gradle.

In my app module, I want my source code to use the RecyclerView and Retrofit defined in libraries , but I can't do it unless I also include retrofit and recyclerview-v7 in my app/build.gradle.

app/main/src/..../HomeActivity.kt

var gridDataset: RecyclerView? = null // RecyclerView not found in classpath

app/build.gradle

implementation fileTree(dir: 'libs', include: ['*.jar'])
implementation project(":libraries")

libraries/build.gradle

implementation "com.android.support:recyclerview-v7:$support_library_version"
implementation "com.squareup.retrofit2:retrofit:2.4.0"
implementation "com.squareup.retrofit2:converter-gson:2.4.0"
implementation "com.squareup.retrofit2:adapter-rxjava2:2.4.0"
implementation "com.squareup.okhttp3:logging-interceptor:3.8.0"

Where did I go wrong? Or is it simply impossible to do that?

Answer 1

specify your dependencies in libraries/build.gradle using api instead of implementation

This should add these dependencies to the class path for any module depending on your libraries module

api "com.android.support:recyclerview-v7:$support_library_version"
api "com.squareup.retrofit2:retrofit:2.4.0"
api "com.squareup.retrofit2:converter-gson:2.4.0"
api "com.squareup.retrofit2:adapter-rxjava2:2.4.0"
api "com.squareup.okhttp3:logging-interceptor:3.8.0"