feat: adding kodein as dependency injection framework

app/build.gradle

@@ -94,6 +94,8 @@ dependencies {
     implementation Dependencies.firebaseAuth
     implementation Dependencies.googleAuth
     implementation Dependencies.notification
+    implementation Dependencies.kodein
+    implementation Dependencies.kodeinConf
 
     testImplementation DependenciesTest.junit4
     androidTestImplementation DependenciesTest.androidRunner

app/src/main/java/gdg/aracaju/GdgApplication.kt

@@ -2,11 +2,30 @@ package gdg.aracaju
 
 import android.app.Application
 import com.jakewharton.threetenabp.AndroidThreeTen
+import gdg.aracaju.data.di.dataModule
+import gdg.aracaju.view.di.viewModule
+import org.kodein.di.Kodein
+import org.kodein.di.KodeinAware
+import org.kodein.di.conf.ConfigurableKodein
+import org.kodein.di.generic.bind
+import org.kodein.di.generic.provider
 
-class GdgApplication : Application() {
+class GdgApplication : Application(), KodeinAware {
+
+    private val appModule = Kodein.Module(name = "application"){
+        bind() from provider {
+            this@GdgApplication as Application
+        }
+    }
+
+    override val kodein: Kodein = ConfigurableKodein(mutable = true).apply {
+        addImport(appModule)
+        addImport(dataModule)
+        addImport(viewModule)
+    }
 
     override fun onCreate() {
         super.onCreate()
-        AndroidThreeTen.init(this);
+        AndroidThreeTen.init(this)
     }
 }

app/src/main/java/gdg/aracaju/data/di/injection.kt

@@ -0,0 +1,26 @@
+package gdg.aracaju.data.di
+
+import gdg.aracaju.data.api.detail.DetailRepository
+import gdg.aracaju.data.api.events.EventsRepository
+import gdg.aracaju.data.api.login.AuthRepository
+import gdg.aracaju.domain.service.AuthService
+import gdg.aracaju.domain.service.DetailService
+import gdg.aracaju.domain.service.EventsService
+import org.kodein.di.Kodein
+import org.kodein.di.generic.bind
+import org.kodein.di.generic.singleton
+
+val dataModule = Kodein.Module("data") {
+
+    bind<DetailService>() with singleton  {
+        DetailRepository()
+    }
+
+    bind<EventsService>() with singleton  {
+        EventsRepository()
+    }
+
+    bind<AuthService>() with singleton  {
+        AuthRepository()
+    }
+}

app/src/main/java/gdg/aracaju/view/detail/detail/DetailActivity.kt

@@ -9,33 +9,34 @@ import android.view.MenuItem
 import androidx.appcompat.app.AppCompatActivity
 import androidx.core.view.isVisible
 import androidx.lifecycle.Observer
-import androidx.lifecycle.ViewModelProviders
 import androidx.recyclerview.widget.LinearLayoutManager
 import com.xwray.groupie.GroupAdapter
 import com.xwray.groupie.kotlinandroidextensions.ViewHolder
-import gdg.aracaju.data.api.detail.DetailRepository
 import gdg.aracaju.domain.Date
 import gdg.aracaju.domain.model.Detail
 import gdg.aracaju.domain.model.ScreenState
 import gdg.aracaju.news.R
 import gdg.aracaju.view.detail.map.MapsDetailActivity
+import gdg.aracaju.view.kodein
+import gdg.aracaju.view.viewModel
 import kotlinx.android.synthetic.main.activity_detail.*
 import kotlinx.android.synthetic.main.content_detail.*
 import kotlinx.android.synthetic.main.error_state_layout.*
+import org.kodein.di.Kodein
+import org.kodein.di.KodeinAware
 
-class DetailActivity : AppCompatActivity() {
+class DetailActivity : AppCompatActivity(), KodeinAware {
+
+    override val kodein: Kodein = kodein()
 
-    private val service by lazy { DetailRepository() }
     private val sharer by lazy { Sharer(this) }
     private val adapter by lazy { GroupAdapter<ViewHolder>() }
     private val manager by lazy { LinearLayoutManager(this) }
     private val calendar by lazy { CalendarEvent(this) }
 
     private val id by lazy { intent?.extras?.get(ID) as? Int }
 
-    private val viewModel by lazy {
-        ViewModelProviders.of(this, DetailViewModelFactory(service)).get(DetailViewModel::class.java)
-    }
+    private val viewModel by viewModel<DetailViewModel>()
 
     override fun onCreate(savedInstanceState: Bundle?) {
         super.onCreate(savedInstanceState)

app/src/main/java/gdg/aracaju/view/di/injection.kt

@@ -0,0 +1,43 @@
+package gdg.aracaju.view.di
+
+import gdg.aracaju.domain.service.DetailService
+import gdg.aracaju.domain.service.EventsService
+import gdg.aracaju.view.detail.detail.DetailViewModel
+import gdg.aracaju.view.detail.detail.DetailViewModelFactory
+import gdg.aracaju.view.detail.detail.Sharer
+import gdg.aracaju.view.login.AuthControl
+import gdg.aracaju.view.login.AuthManager
+import gdg.aracaju.view.login.LoginViewModel
+import gdg.aracaju.view.login.LoginViewModelFactory
+import gdg.aracaju.view.news.DashboardViewModel
+import gdg.aracaju.view.news.DashboardViewModelFactory
+import org.kodein.di.Kodein
+import org.kodein.di.generic.bind
+import org.kodein.di.generic.instance
+import org.kodein.di.generic.provider
+
+val viewModule = Kodein.Module("view"){
+
+    bind<AuthControl>() with provider {
+        AuthManager(
+            activity = instance(),
+            service = instance()
+        )
+    }
+
+    bind<DashboardViewModel>() with provider {
+        val service = instance<EventsService>()
+        val auth = instance<AuthControl>()
+        DashboardViewModelFactory(service, auth).create(DashboardViewModel::class.java)
+    }
+
+    bind<DetailViewModel>() with provider {
+        val service = instance<DetailService>()
+        DetailViewModelFactory(service).create(DetailViewModel::class.java)
+    }
+
+    bind<LoginViewModel>() with provider {
+        val service = instance<AuthControl>()
+        LoginViewModelFactory(service).create(LoginViewModel::class.java)
+    }
+}

app/src/main/java/gdg/aracaju/view/injection_extensions.kt

@@ -0,0 +1,35 @@
+package gdg.aracaju.view
+
+import androidx.appcompat.app.AppCompatActivity
+import androidx.fragment.app.FragmentActivity
+import androidx.lifecycle.ViewModel
+import androidx.lifecycle.ViewModelProvider
+import androidx.lifecycle.ViewModelProviders
+import org.kodein.di.Kodein
+import org.kodein.di.KodeinAware
+import org.kodein.di.direct
+import org.kodein.di.generic.instance
+import org.kodein.di.generic.instanceOrNull
+
+@Suppress("UNCHECKED_CAST")
+inline fun <reified VM : ViewModel> KodeinAware.viewModel() = lazy {
+
+    val factory = object : ViewModelProvider.Factory {
+        override fun <Model : ViewModel> create(klass: Class<Model>) =
+            direct.instance<VM>() as Model
+    }
+
+    val host = direct.instanceOrNull<FragmentActivity>()
+        ?: throw IllegalStateException("Host Activity not attached on this graph")
+
+    ViewModelProviders.of(host, factory).get(VM::class.java)
+}
+
+fun AppCompatActivity.kodein(bindings: Kodein.MainBuilder.() -> Unit = {}) = Kodein.lazy {
+
+    val parentKodein = (applicationContext as KodeinAware).kodein
+
+    extend(parentKodein)
+
+    bindings.invoke(this)
+}

app/src/main/java/gdg/aracaju/view/login/LoginActivity.kt

@@ -5,25 +5,24 @@ import android.os.Bundle
 import androidx.appcompat.app.AppCompatActivity
 import androidx.core.view.isVisible
 import androidx.lifecycle.Observer
-import androidx.lifecycle.ViewModelProviders
 import com.google.android.material.snackbar.Snackbar.LENGTH_SHORT
 import com.google.android.material.snackbar.Snackbar.make
-import gdg.aracaju.data.api.login.AuthRepository
 import gdg.aracaju.domain.model.LoginState
 import gdg.aracaju.domain.model.ScreenState
 import gdg.aracaju.news.R
+import gdg.aracaju.view.kodein
 import gdg.aracaju.view.login.AuthManager.Companion.RC_SIGN_IN
 import gdg.aracaju.view.news.DashboardActivity
 import kotlinx.android.synthetic.main.activity_login.*
+import gdg.aracaju.view.viewModel
+import org.kodein.di.Kodein
+import org.kodein.di.KodeinAware
 
-class LoginActivity : AppCompatActivity() {
+class LoginActivity : AppCompatActivity(), KodeinAware {
 
-    private val service by lazy { AuthRepository() }
-    private val manager by lazy { AuthManager(this, service) }
+    override val kodein: Kodein = kodein()
 
-    private val viewModel by lazy {
-        ViewModelProviders.of(this, LoginViewModelFactory(manager)).get(LoginViewModel::class.java)
-    }
+    private val viewModel by viewModel<LoginViewModel>()
 
     override fun onCreate(savedInstanceState: Bundle?) {
         super.onCreate(savedInstanceState)

app/src/main/java/gdg/aracaju/view/news/DashboardActivity.kt

@@ -7,34 +7,31 @@ import android.util.Log
 import androidx.appcompat.app.AppCompatActivity
 import androidx.core.view.isVisible
 import androidx.lifecycle.Observer
-import androidx.lifecycle.ViewModelProviders
 import androidx.recyclerview.widget.LinearLayoutManager
 import com.google.android.gms.tasks.OnCompleteListener
 import com.google.firebase.iid.FirebaseInstanceId
 import com.xwray.groupie.GroupAdapter
 import com.xwray.groupie.kotlinandroidextensions.ViewHolder
-import gdg.aracaju.data.api.events.EventsRepository
 import gdg.aracaju.data.api.login.AuthRepository
 import gdg.aracaju.domain.model.Event
 import gdg.aracaju.domain.model.ScreenState
 import gdg.aracaju.news.R
 import gdg.aracaju.view.detail.detail.DetailActivity
-import gdg.aracaju.view.login.AuthManager
 import gdg.aracaju.view.login.LoginActivity
+import gdg.aracaju.view.kodein
+import gdg.aracaju.view.viewModel
 import kotlinx.android.synthetic.main.activity_main.*
 import kotlinx.android.synthetic.main.error_state_layout.*
+import org.kodein.di.Kodein
+import org.kodein.di.KodeinAware
 
-internal class DashboardActivity : AppCompatActivity() {
+internal class DashboardActivity : AppCompatActivity(), KodeinAware {
+
+    override val kodein: Kodein = kodein()
 
-    private val eventService by lazy { EventsRepository() }
     private val authService by lazy { AuthRepository() }
-    private val auth by lazy { AuthManager(this, authService) }
 
-    private val viewModel by lazy {
-        ViewModelProviders
-            .of(this, DashboardViewModelFactory(eventService, auth))
-            .get(DashboardViewModel::class.java)
-    }
+    private val viewModel by viewModel<DashboardViewModel>()
     private val adapter by lazy { GroupAdapter<ViewHolder>() }
     private val manager by lazy { LinearLayoutManager(this) }
     private val bottomNavDrawerFragment by lazy { BottomNavigationDrawerFragment() }

buildSrc/src/main/java/Dependencies.kt

@@ -19,6 +19,7 @@ object Versions {
     const val notification = "17.6.0"
     const val fabric = "1.26.1"
     const val crashlytics = "2.9.9"
+    const val kodein = "6.0.1"
 }
 
 object Dependencies {
@@ -54,6 +55,9 @@ object Dependencies {
     const val threetenabp = "com.jakewharton.threetenabp:threetenabp:${Versions.threeten}"
 
     const val notification = "com.google.firebase:firebase-messaging:${Versions.notification}"
+
+    val kodein = "org.kodein.di:kodein-di-generic-jvm:${Versions.kodein}"
+    val kodeinConf = "org.kodein.di:kodein-di-conf-jvm:${Versions.kodein}"
 }
 
 object VersionsTest {