[Crane] Adds Hilt to the project

Crane/README.md

@@ -32,6 +32,38 @@ implemented using a different Activity will be displayed. In there, you can see
 embedded in Compose and Compose buttons updating the Android View. Notice how you can also
 interact with the `MapView` seamlessly.
 
+## Hilt
+
+Crane uses [Hilt][hilt] to manage its dependencies. The Hilt's ViewModel extension (with the
+`@ViewModelInject` annotation) works perfectly with Compose's ViewModel integration (`viewModel()`
+composable function) as you can see in the following snippet of code. `viewModel()` will
+automatically use the factory that Hilt creates for the ViewModel:
+
+```
+class MainViewModel @ViewModelInject constructor(
+    private val destinationsRepository: DestinationsRepository,
+    @DefaultDispatcher private val defaultDispatcher: CoroutineDispatcher,
+    datesRepository: DatesRepository
+) : ViewModel() { ... }
+
+@Composable
+fun CraneHomeContent(...) {
+    val viewModel: MainViewModel = viewModel()
+    ...
+}
+```
+
+Disclaimer: Passing dependencies to a ViewModel which are not available at compile time (which is
+sometimes called _assisted injection_) doesn't work as you might expect using `viewModel()`.
+Compose's ViewModel integration cannot currently scope a ViewModel to a given composable. Instead
+it is always scoped to the host Activity or Fragment. This means that calling `viewModel()` with
+different factories in the same host Activity/Fragment don't have the desired effect; the _first_
+factory will be always used.
+
+This is the case of the [DetailsViewModel](detailsViewModel), which takes the name of
+a `City` as a parameter to load the required information for the screen. However, the above isn't a
+problem in this sample, since `DetailsScreen` is always used in it's own newly launched Activity.
+
 ## Google Maps SDK
 
 To get the MapView working, you need to get an API key as
@@ -79,6 +111,8 @@ limitations under the License.
 [details]: app/src/main/java/androidx/compose/samples/crane/details/DetailsActivity.kt
 [data]: app/src/main/java/androidx/compose/samples/crane/data/CraneData.kt
 [mainViewModel]: app/src/main/java/androidx/compose/samples/crane/home/MainViewModel.kt
+[detailsViewModel]: app/src/main/java/androidx/compose/samples/crane/details/DetailsViewModel.kt
 [homeTest]: app/src/androidTest/java/androidx/compose/samples/crane/home/HomeTest.kt
 [detailsTest]: app/src/androidTest/java/androidx/compose/samples/crane/details/DetailsActivityTest.kt
 [coil-accompanist]: https://github.com/chrisbanes/accompanist
+[hilt]: https://d.android.com/hilt

Crane/app/build.gradle

@@ -19,6 +19,8 @@ import com.example.crane.buildsrc.Libs
 plugins {
     id 'com.android.application'
     id 'kotlin-android'
+    id 'kotlin-kapt'
+    id 'dagger.hilt.android.plugin'
 }
 
 // Reads the Google maps key that is used in the AndroidManifest
@@ -36,7 +38,13 @@ android {
         versionCode 1
         versionName "1.0"
         vectorDrawables.useSupportLibrary = true
-        testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
+        testInstrumentationRunner "androidx.compose.samples.crane.CustomTestRunner"
+
+        javaCompileOptions {
+            annotationProcessorOptions {
+                arguments["dagger.hilt.disableModulesHaveInstallInCheck"] = "true"
+            }
+        }
 
         manifestPlaceholders = [ googleMapsKey : properties.getProperty("google.maps.key", "") ]
     }
@@ -81,14 +89,22 @@ android {
         resValues false
         shaders false
     }
+
     composeOptions {
         kotlinCompilerVersion Libs.Kotlin.version
         kotlinCompilerExtensionVersion Libs.AndroidX.Compose.version
     }
+
+    packagingOptions {
+        exclude "META-INF/licenses/**"
+        exclude "META-INF/AL2.0"
+        exclude "META-INF/LGPL2.1"
+    }
 }
 
 dependencies {
     implementation Libs.Kotlin.stdlib
+    implementation Libs.Kotlin.Coroutines.android
     implementation Libs.googleMaps
 
     implementation Libs.AndroidX.Compose.runtime
@@ -98,12 +114,27 @@ dependencies {
     implementation Libs.AndroidX.Compose.layout
     implementation Libs.AndroidX.Compose.animation
     implementation Libs.AndroidX.UI.tooling
-
     implementation Libs.Accompanist.coil
 
+    implementation Libs.AndroidX.Lifecycle.viewModelKtx
+    implementation Libs.Hilt.android
+    implementation Libs.Hilt.AndroidX.viewModel
+    compileOnly Libs.AssistedInjection.dagger
+    kapt Libs.Hilt.compiler
+    kapt Libs.Hilt.AndroidX.compiler
+    kapt Libs.AssistedInjection.processor
+
+    androidTestImplementation Libs.JUnit.junit
     androidTestImplementation Libs.AndroidX.Test.runner
     androidTestImplementation Libs.AndroidX.Test.espressoCore
     androidTestImplementation Libs.AndroidX.Test.rules
     androidTestImplementation Libs.AndroidX.Test.Ext.junit
+    androidTestImplementation Libs.Kotlin.Coroutines.test
     androidTestImplementation Libs.AndroidX.Compose.uiTest
+    androidTestImplementation Libs.Hilt.android
+    androidTestImplementation Libs.Hilt.AndroidX.viewModel
+    androidTestImplementation Libs.Hilt.testing
+    kaptAndroidTest Libs.Hilt.compiler
+    kaptAndroidTest Libs.Hilt.AndroidX.compiler
+    kaptAndroidTest Libs.AssistedInjection.processor
 }

Crane/app/src/androidTest/java/androidx/compose/samples/crane/CustomTestRunner.kt

@@ -0,0 +1,28 @@
+/*
+ * Copyright 2020 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package androidx.compose.samples.crane
+
+import android.app.Application
+import android.content.Context
+import androidx.test.runner.AndroidJUnitRunner
+import dagger.hilt.android.testing.HiltTestApplication
+
+class CustomTestRunner : AndroidJUnitRunner() {
+    override fun newApplication(cl: ClassLoader?, name: String?, context: Context?): Application {
+        return super.newApplication(cl, HiltTestApplication::class.java.name, context)
+    }
+}

Crane/app/src/androidTest/java/androidx/compose/samples/crane/calendar/CalendarTest.kt

@@ -17,66 +17,61 @@
 package androidx.compose.samples.crane.calendar
 
 import androidx.compose.material.Surface
-import androidx.compose.samples.crane.base.ServiceLocator
-import androidx.compose.samples.crane.calendar.model.CalendarDay
-import androidx.compose.samples.crane.calendar.model.CalendarMonth
-import androidx.compose.samples.crane.calendar.model.DaySelected
 import androidx.compose.samples.crane.calendar.model.DaySelectedStatus
 import androidx.compose.samples.crane.calendar.model.DaySelectedStatus.FirstDay
 import androidx.compose.samples.crane.calendar.model.DaySelectedStatus.FirstLastDay
 import androidx.compose.samples.crane.calendar.model.DaySelectedStatus.LastDay
 import androidx.compose.samples.crane.calendar.model.DaySelectedStatus.NoSelected
 import androidx.compose.samples.crane.calendar.model.DaySelectedStatus.Selected
+import androidx.compose.samples.crane.data.DatesRepository
+import androidx.compose.samples.crane.di.DispatchersModule
 import androidx.compose.samples.crane.ui.CraneTheme
 import androidx.ui.test.ComposeTestRule
 import androidx.ui.test.SemanticsMatcher
 import androidx.ui.test.assertLabelEquals
-import androidx.ui.test.createComposeRule
+import androidx.ui.test.createAndroidComposeRule
 import androidx.ui.test.onNodeWithLabel
 import androidx.ui.test.performClick
 import androidx.ui.test.performScrollTo
-import org.junit.After
+import dagger.hilt.android.testing.HiltAndroidRule
+import dagger.hilt.android.testing.HiltAndroidTest
+import dagger.hilt.android.testing.UninstallModules
 import org.junit.Before
 import org.junit.Rule
 import org.junit.Test
+import javax.inject.Inject
 
+@UninstallModules(DispatchersModule::class)
+@HiltAndroidTest
 class CalendarTest {
 
-    @get:Rule
-    val composeTestRule = createComposeRule(disableTransitions = true)
-
-    var dateSelected = ""
-    private val onDayClicked: (CalendarDay, CalendarMonth) -> Unit = { day, month ->
-        dateSelected = "${month.name} ${day.value}"
-        ServiceLocator.datesSelected.daySelected(
-            DaySelected(
-                day = day.value.toInt(),
-                month = month
-            )
-        )
-    }
+    @get:Rule(order = 0)
+    var hiltRule = HiltAndroidRule(this)
+
+    @get:Rule(order = 1)
+    val composeTestRule = createAndroidComposeRule<CalendarActivity>()
+
+    @Inject
+    lateinit var datesRepository: DatesRepository
 
     @Before
     fun setUp() {
+        hiltRule.inject()
+
         composeTestRule.setContent {
             CraneTheme {
                 Surface {
-                    Calendar(onDayClicked)
+                    CalendarScreen(onBackPressed = {})
                 }
             }
         }
     }
 
-    @After
-    fun tearDown() {
-        ServiceLocator.datesSelected.clearDates()
-    }
-
     @Test
     fun scrollsToTheBottom() {
         composeTestRule.onNodeWithLabel("January 1").assertExists()
         composeTestRule.onNodeWithLabel("December 31").performScrollTo().performClick()
-        assert(dateSelected == "December 31")
+        assert(datesRepository.datesSelected.toString() == "Dec 31")
     }
 
     @Test

Crane/app/src/androidTest/java/androidx/compose/samples/crane/details/DetailsActivityTest.kt

@@ -17,8 +17,10 @@
 package androidx.compose.samples.crane.details
 
 import androidx.compose.samples.crane.R
+import androidx.compose.samples.crane.data.DestinationsRepository
 import androidx.compose.samples.crane.data.ExploreModel
 import androidx.compose.samples.crane.data.MADRID
+import androidx.compose.samples.crane.di.DispatchersModule
 import androidx.test.espresso.Espresso.onView
 import androidx.test.espresso.assertion.ViewAssertions.matches
 import androidx.test.espresso.matcher.ViewMatchers.isDisplayed
@@ -31,16 +33,30 @@ import androidx.ui.test.onNodeWithText
 import com.google.android.libraries.maps.MapView
 import com.google.android.libraries.maps.model.CameraPosition
 import com.google.android.libraries.maps.model.LatLng
+import dagger.hilt.android.testing.HiltAndroidRule
+import dagger.hilt.android.testing.HiltAndroidTest
+import dagger.hilt.android.testing.UninstallModules
+import org.junit.Before
 import org.junit.Rule
 import org.junit.Test
 import java.util.concurrent.CountDownLatch
+import javax.inject.Inject
 
+@UninstallModules(DispatchersModule::class)
+@HiltAndroidTest
 class DetailsActivityTest {
 
-    private val expectedDescription = "description"
-    private val testExploreModel = ExploreModel(MADRID, expectedDescription, "imageUrl")
+    @Inject
+    lateinit var destinationsRepository: DestinationsRepository
+    lateinit var cityDetails: ExploreModel
 
-    @get:Rule
+    private val city = MADRID
+    private val testExploreModel = ExploreModel(city, "description", "imageUrl")
+
+    @get:Rule(order = 0)
+    var hiltRule = HiltAndroidRule(this)
+
+    @get:Rule(order = 1)
     val composeTestRule = AndroidComposeTestRule(
         ActivityScenarioRule<DetailsActivity>(
             createDetailsActivityIntent(
@@ -50,10 +66,16 @@ class DetailsActivityTest {
         )
     )
 
+    @Before
+    fun setUp() {
+        hiltRule.inject()
+        cityDetails = destinationsRepository.getDestination(MADRID.name)!!
+    }
+
     @Test
     fun mapView_cameraPositioned() {
-        composeTestRule.onNodeWithText(MADRID.nameToDisplay).assertIsDisplayed()
-        composeTestRule.onNodeWithText(expectedDescription).assertIsDisplayed()
+        composeTestRule.onNodeWithText(cityDetails.city.nameToDisplay).assertIsDisplayed()
+        composeTestRule.onNodeWithText(cityDetails.description).assertIsDisplayed()
         onView(withId(R.id.map)).check(matches(isDisplayed()))
 
         var cameraPosition: CameraPosition? = null

Crane/app/src/androidTest/java/androidx/compose/samples/crane/di/TestDispatchersModule.kt

@@ -0,0 +1,37 @@
+/*
+ * Copyright 2020 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+@file:Suppress("DEPRECATION")
+
+package androidx.compose.samples.crane.di
+
+import dagger.Module
+import dagger.Provides
+import dagger.hilt.InstallIn
+import dagger.hilt.android.components.ApplicationComponent
+import kotlinx.coroutines.CoroutineDispatcher
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.ExperimentalCoroutinesApi
+
+@OptIn(ExperimentalCoroutinesApi::class)
+@Module
+@InstallIn(ApplicationComponent::class)
+class TestDispatchersModule {
+
+    @Provides
+    @DefaultDispatcher
+    fun provideDefaultDispatcher(): CoroutineDispatcher = Dispatchers.Unconfined
+}

Crane/app/src/androidTest/java/androidx/compose/samples/crane/home/HomeTest.kt

@@ -17,18 +17,27 @@
 package androidx.compose.samples.crane.home
 
 import androidx.compose.material.Surface
+import androidx.compose.samples.crane.di.DispatchersModule
 import androidx.compose.samples.crane.ui.CraneTheme
-import androidx.ui.test.createComposeRule
+import androidx.ui.test.createAndroidComposeRule
 import androidx.ui.test.onNodeWithText
 import androidx.ui.test.performClick
+import dagger.hilt.android.testing.HiltAndroidRule
+import dagger.hilt.android.testing.HiltAndroidTest
+import dagger.hilt.android.testing.UninstallModules
 import org.junit.Before
 import org.junit.Rule
 import org.junit.Test
 
+@UninstallModules(DispatchersModule::class)
+@HiltAndroidTest
 class HomeTest {
 
-    @get:Rule
-    val composeTestRule = createComposeRule(disableTransitions = true)
+    @get:Rule(order = 0)
+    var hiltRule = HiltAndroidRule(this)
+
+    @get:Rule(order = 1)
+    val composeTestRule = createAndroidComposeRule<MainActivity>()
 
     @Before
     fun setUp() {

Crane/app/src/main/AndroidManifest.xml

@@ -21,6 +21,7 @@
     <uses-permission android:name="android.permission.INTERNET" />
 
     <application
+        android:name=".CraneApplication"
         android:allowBackup="true"
         android:icon="@mipmap/ic_launcher"
         android:label="@string/app_name"

Crane/app/src/main/java/androidx/compose/samples/crane/base/ServiceLocator.kt → Crane/app/src/main/java/androidx/compose/samples/crane/CraneApplication.kt

@@ -14,10 +14,10 @@
  * limitations under the License.
  */
 
-package androidx.compose.samples.crane.base
+package androidx.compose.samples.crane
 
-import androidx.compose.samples.crane.calendar.model.DatesSelectedState
+import android.app.Application
+import dagger.hilt.android.HiltAndroidApp
 
-object ServiceLocator {
-    val datesSelected = DatesSelectedState()
-}
+@HiltAndroidApp
+class CraneApplication : Application()