In an attempt to hide concrete classes you don t want your team to accidentally use Which option would you go for Interface and concrete ```interface CrashReporterService fun logFatal e Exception class FirebaseCrashReporterService CrashReporterService override fun logFatal e Exception do something ``` Option one dont add the concrete to nav graph and just create it at the Provider ``` Module object FirebaseCrashReporterModule JvmStatic Provides fun firebaseCrashReporter dependencies CrashReporter return FirebaseCrashReporter ``` Option two use a qualifier to make the type harder to accidentally use ``` Module InstallIn SingletonComponent class abstract class AppInterfaceModule Singleton Binds abstract fun bindsCrashReporterService Named placeholder qualifier service FirebaseCrashReporterService CrashReporterService Module InstallIn SingletonComponent class class AppImplModule Singleton Provides Named placeholder qualifier fun bindsCrashReporterService FirebaseCrashReporterService return FirebaseCrashReporterService ```

interface CrashReporterService {
  fun logFatal(e: Exception)
}

class FirebaseCrashReporterService : CrashReporterService {
  override fun logFatal(e: Exception) {
    // do something
  }
}

Option 1️⃣ :(dont add the concrete to nav graph and just create it at the Provider)

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@Module
object FirebaseCrashReporterModule {
    
    @JvmStatic
    @Provides
    fun firebaseCrashReporter(dependencies..) : CrashReporter {
        return FirebaseCrashReporter(...)
    }
}

Option 2️⃣: (use a qualifier to make the type "harder" to accidentally use)

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@Module
@InstallIn(SingletonComponent::class)
abstract class AppInterfaceModule {
  @Singleton
  @Binds
  abstract fun bindsCrashReporterService(
      @Named("placeholder_qualifier") service: FirebaseCrashReporterService
  ): CrashReporterService
}

@Module
@InstallIn(SingletonComponent::class)
class AppImplModule {
  @Singleton
  @Provides
  @Named("placeholder_qualifier")
  fun bindsCrashReporterService(): FirebaseCrashReporterService {
    return FirebaseCrashReporterService()
  }
}

1️⃣ 5

2️⃣ 1

ashdavies

12/01/2021, 6:42 PM

Use a factory function to hide the class definition entirely

👍 1

Copy code

interface CrashReporterService {
  fun logFatal(e: Exception)
}

internal class FirebaseCrashReporterService : CrashReporterService {
  override fun logFatal(e: Exception) {
    // do something
  }
}

fun CrashReporterService(): CrashReporterService = FirebaseCrashReporterService()

Colton Idle

12/01/2021, 7:03 PM

ooh. Yet another option...

ursus

12/01/2021, 11:47 PM

You just moved di code to you business code. Dont do that. do 1 if you do modules, do 2 if you do @inject ctors its a good thing there is a choice, remember

👍 1

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