Kotlinized the entire app for Kotlin beginners

app/build.gradle

@@ -1,14 +1,16 @@
 apply plugin: 'com.android.application'
-apply plugin: 'com.neenbedankt.android-apt'
+apply plugin: 'kotlin-android'
+apply plugin: 'kotlin-android-extensions'
+apply plugin: 'kotlin-kapt'
 
 android {
-    compileSdkVersion 23
-    buildToolsVersion "23.0.2"
+    compileSdkVersion 27
+    buildToolsVersion "27.0.3"
 
     defaultConfig {
         applicationId "io.caster.simplemvp"
         minSdkVersion 16
-        targetSdkVersion 23
+        targetSdkVersion 27
         versionCode 1
         versionName "1.0"
     }
@@ -20,16 +22,42 @@ android {
     }
 }
 
+kotlin {
+    experimental {
+        coroutines "enable"
+    }
+}
+
+androidExtensions {
+    experimental true
+}
+
+kapt {
+    generateStubs true
+}
+
 dependencies {
-    compile fileTree(dir: 'libs', include: ['*.jar'])
-    testCompile 'junit:junit:4.12'
-    testCompile "org.mockito:mockito-core:1.10.19"
+    implementation fileTree(dir: 'libs', include: ['*.jar'])
+
+    // Test dependencies
+    testImplementation 'junit:junit:4.12'
+    testImplementation 'org.mockito:mockito-core:2.16.0'
+
+    // Kotlin dependencies
+    implementation "org.jetbrains.kotlin:kotlin-stdlib-jre7:$kotlinVer"
+    implementation "org.jetbrains.anko:anko:$ankoVer"
+    implementation "org.jetbrains.anko:anko-design:$ankoVer"
 
-    compile 'com.android.support:appcompat-v7:23.1.1'
-    compile 'com.android.support:design:23.1.1'
+    // Support Library dependencies
+    implementation 'com.android.support:appcompat-v7:27.1.0'
+    implementation 'com.android.support:design:27.1.0'
+    implementation 'com.android.support:support-v4:27.1.0'
 
-    compile 'com.jakewharton:butterknife:7.0.1'
-    compile 'com.google.dagger:dagger:2.0.2'
-    apt 'com.google.dagger:dagger-compiler:2.0.2'
-    provided 'javax.annotation:jsr250-api:1.0'
+    // Dagger 2 dependencies
+    implementation 'com.google.dagger:dagger:2.15'
+    implementation 'com.google.dagger:dagger-android:2.15'
+    implementation 'com.google.dagger:dagger-android-support:2.15'
+    kapt 'com.google.dagger:dagger-compiler:2.15'
+    kapt 'com.google.dagger:dagger-android-processor:2.15'
+    compileOnly 'javax.annotation:jsr250-api:1.0'
 }

app/src/androidTest/java/io/caster/simplemvp/ApplicationTest.kt

@@ -0,0 +1,9 @@
+package io.caster.simplemvp
+
+import android.app.Application
+import android.test.ApplicationTestCase
+
+/**
+ * [Testing Fundamentals](http://d.android.com/tools/testing/testing_android.html)
+ */
+class ApplicationTest : ApplicationTestCase<Application>(Application::class.java)

app/src/main/java/io/caster/simplemvp/AppComponent.kt

@@ -0,0 +1,11 @@
+package io.caster.simplemvp
+
+import dagger.Component
+import io.caster.simplemvp.view.fragment.UserFragment
+import javax.inject.Singleton
+
+@Singleton
+@Component(modules = [AppModule::class])
+interface AppComponent {
+    fun inject(target: UserFragment)
+}

app/src/main/java/io/caster/simplemvp/AppModule.kt

@@ -0,0 +1,19 @@
+package io.caster.simplemvp
+
+import dagger.Module
+import dagger.Provides
+import io.caster.simplemvp.presentation.UserPresenter
+import io.caster.simplemvp.presentation.UserPresenterImpl
+import io.caster.simplemvp.repository.InMemoryUserRepositoryImpl
+import io.caster.simplemvp.repository.UserRepository
+import javax.inject.Singleton
+
+@Module
+class AppModule {
+    @Provides
+    @Singleton
+    fun provideUserRepository(): UserRepository = InMemoryUserRepositoryImpl()
+
+    @Provides
+    fun provideUserPresenter(userRepository: UserRepository): UserPresenter = UserPresenterImpl(userRepository)
+}

app/src/main/java/io/caster/simplemvp/MvpApplication.kt

@@ -0,0 +1,14 @@
+package io.caster.simplemvp
+
+import android.app.Application
+
+class MvpApplication : Application() {
+
+    var component: AppComponent? = null
+
+    override fun onCreate() {
+        super.onCreate()
+
+        component = DaggerAppComponent.builder().appModule(AppModule()).build()
+    }
+}

app/src/main/java/io/caster/simplemvp/model/User.kt

@@ -0,0 +1,7 @@
+package io.caster.simplemvp.model
+
+data class User (
+    var id: Int = 0,
+    var firstName: String? = null,
+    var lastName: String? = null
+)

app/src/main/java/io/caster/simplemvp/presentation/UserPresenter.kt

@@ -0,0 +1,11 @@
+package io.caster.simplemvp.presentation
+
+import io.caster.simplemvp.view.UserView
+
+interface UserPresenter {
+    fun loadUserDetails()
+
+    fun setView(view: UserView)
+
+    fun saveUser()
+}

app/src/main/java/io/caster/simplemvp/presentation/UserPresenterImpl.kt

@@ -0,0 +1,41 @@
+package io.caster.simplemvp.presentation
+
+import io.caster.simplemvp.model.User
+import io.caster.simplemvp.repository.UserRepository
+import io.caster.simplemvp.view.UserView
+
+class UserPresenterImpl(val userRepository: UserRepository) : UserPresenter {
+
+    private var view: UserView? = null
+    private var u: User? = null
+
+    override fun loadUserDetails() {
+        val userId = view!!.userId
+        u = userRepository.getUser(userId)
+        if (u == null) {
+            view!!.showUserNotFoundMessage()
+        } else {
+            view!!.displayFirstName(u!!.firstName!!)
+            view!!.displayLastName(u!!.lastName!!)
+        }
+    }
+
+    override fun setView(view: UserView) {
+        this.view = view
+        loadUserDetails()
+    }
+
+    override fun saveUser() {
+        if (u != null) {
+            if (view!!.firstName.trim { it <= ' ' } == "" || view!!.lastName.trim { it <= ' ' } == "") {
+                view!!.showUserNameIsRequired()
+            } else {
+                u!!.firstName = view!!.firstName
+                u!!.lastName = view!!.lastName
+                userRepository.save(u!!)
+                view!!.showUserSavedMessage()
+            }
+
+        }
+    }
+}