kirich1409

@Module
interface ActivityBindsModule {

    @Binds
    @IntoMap
    @ActivityKey(MainActivity::class)
    fun bindMainActivityToActivityForMultiBinding(activity: MainActivity): Activity
}

kirich1409

@Module
interface ComponentProvidersModule {

    // Define that a Dagger Component can provide Multibind Map of Activities by class
    @Multibinds
    fun provideActivities(): Map<Class<out Activity>, @JvmSuppressWildcards Activity>
}

kirich1409

@Module
object AppModule {

    @Provides
    fun provideFragmentFactory(
        fragmentProviders: Map<Class<out Fragment>, @JvmSuppressWildcards Provider<Fragment>>
    ): FragmentFactory {
        return InjectFragmentFactory(fragmentProviders)
    }
}

kirich1409

@Component(
    modules = [
        AppModule::class,
        ComponentProvidersModule::class,
        FragmentBindsModule::class,
        ActivityBindsModule::class
    ]
)
interface AppComponent {

kirich1409

class SampleApplication : Application() {

    lateinit var appComponent: AppComponent

    override fun onCreate() {
        super.onCreate()
        appComponent = DaggerAppComponent.create()
        registerActivityLifecycleCallbacks(
            SetFragmentFactoryActivityCallback(appComponent.fragmentFactory)
        )

kirich1409

class SetFragmentFactoryActivityCallback(
    private val newFragmentFactory: FragmentFactory
) : EmptyActivityLifecycleCallbacks {

    private val fragmentLifecycleCallbacks = 
        SetFragmentFactoryFragmentCallback(newFragmentFactory)

    override fun onActivityCreated(activity: Activity, savedInstanceState: Bundle?) {
        if (activity is FragmentActivity) {
            val fragmentManager = activity.supportFragmentManager

kirich1409

<manifest
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    >

    <application
        android:name=".SampleApplication"
        android:appComponentFactory="com.kirich1409.android.inject.InjectComponentFactory"
        tools:replace="android:appComponentFactory"
        >

kirich1409

class InjectFragmentFactory(
    private val providers: Map<String, Provider<Fragment>>
) : FragmentFactory() {

    override fun instantiate(classLoader: ClassLoader, className: String): Fragment {
        return providers[className]?.get() ?: super.instantiate(classLoader, className)
    }

    companion object {

kirich1409

@RequiresApi(Build.VERSION_CODES.P)
// We still need default constructor for AppComponentFactory
class InjectComponentFactory : AppComponentFactory() {

    private lateinit var application: SampleApplication

    private val activityProviders: Map<String, Provider<Activity>> by lazy {
        application.appComponent.activityProviders
            .mapKeys { (key, _) -> key.name }
    }

kirich1409

class MyActivity @Inject constructor(
  private val dependency: Dependency
) : AppCompatActivity()


class MyFragment @Inject constructor(
  private val dependency: Dependency
) : Fragment()