Migrate to type-safe Navigation and enable predictive back animations (…

…#22)

* migrate to type-safe navigation screens and upgrade to latest compose versions

* enable predictive back animations

* shorten lines in NavigationCommand and PokemonType

* change NavigationCommand to a sealed interface

* fix spotless error

app/build.gradle.kts

@@ -7,7 +7,7 @@ plugins {
   id("skydoves.pokedex.android.application.compose")
   id("skydoves.pokedex.android.hilt")
   id("skydoves.pokedex.spotless")
-  id("kotlin-parcelize")
+  alias(libs.plugins.kotlin.parcelize)
   alias(libs.plugins.baselineprofile)
 }
 

app/src/main/AndroidManifest.xml

@@ -22,6 +22,7 @@ xmlns:tools="http://schemas.android.com/tools">
 <application
   android:name=".PokedexApp"
   android:allowBackup="false"
+  android:enableOnBackInvokedCallback="true"
   android:icon="@mipmap/ic_launcher"
   android:label="@string/app_name"
   android:supportsRtl="true"

app/src/main/kotlin/com/skydoves/pokedex/compose/MainActivity.kt

@@ -23,6 +23,7 @@ import androidx.activity.enableEdgeToEdge
 import androidx.compose.runtime.CompositionLocalProvider
 import com.skydoves.pokedex.compose.core.navigation.AppComposeNavigator
 import com.skydoves.pokedex.compose.core.navigation.LocalComposeNavigator
+import com.skydoves.pokedex.compose.core.navigation.PokedexScreen
 import com.skydoves.pokedex.compose.ui.PokedexMain
 import dagger.hilt.android.AndroidEntryPoint
 import javax.inject.Inject
@@ -31,7 +32,7 @@ import javax.inject.Inject
 class MainActivity : ComponentActivity() {
 
   @Inject
-  internal lateinit var composeNavigator: AppComposeNavigator
+  internal lateinit var composeNavigator: AppComposeNavigator<PokedexScreen>
 
   override fun onCreate(savedInstanceState: Bundle?) {
     enableEdgeToEdge()

app/src/main/kotlin/com/skydoves/pokedex/compose/navigation/PokedexNavHost.kt

@@ -20,14 +20,14 @@ import androidx.compose.animation.SharedTransitionLayout
 import androidx.compose.runtime.Composable
 import androidx.navigation.NavHostController
 import androidx.navigation.compose.NavHost
-import com.skydoves.pokedex.compose.core.navigation.PokedexScreens
+import com.skydoves.pokedex.compose.core.navigation.PokedexScreen
 
 @Composable
 fun PokedexNavHost(navHostController: NavHostController) {
   SharedTransitionLayout {
     NavHost(
       navController = navHostController,
-      startDestination = PokedexScreens.Home.route,
+      startDestination = PokedexScreen.Home,
     ) {
       pokedexNavigation()
     }

app/src/main/kotlin/com/skydoves/pokedex/compose/navigation/PokedexNavigation.kt

@@ -19,19 +19,18 @@ package com.skydoves.pokedex.compose.navigation
 import androidx.compose.animation.SharedTransitionScope
 import androidx.navigation.NavGraphBuilder
 import androidx.navigation.compose.composable
-import com.skydoves.pokedex.compose.core.navigation.PokedexScreens
+import com.skydoves.pokedex.compose.core.navigation.PokedexScreen
 import com.skydoves.pokedex.compose.feature.details.PokedexDetails
 import com.skydoves.pokedex.compose.feature.home.PokedexHome
 
 context(SharedTransitionScope)
 fun NavGraphBuilder.pokedexNavigation() {
-  composable(route = PokedexScreens.Home.name) {
+  composable<PokedexScreen.Home> {
     PokedexHome(this)
   }
 
-  composable(
-    route = PokedexScreens.Details.name,
-    arguments = PokedexScreens.Details.navArguments,
+  composable<PokedexScreen.Details>(
+    typeMap = PokedexScreen.Details.typeMap,
   ) {
     PokedexDetails(this)
   }

app/src/main/kotlin/com/skydoves/pokedex/compose/ui/PokedexMain.kt

@@ -21,10 +21,11 @@ import androidx.compose.runtime.LaunchedEffect
 import androidx.navigation.compose.rememberNavController
 import com.skydoves.pokedex.compose.core.designsystem.theme.PokedexTheme
 import com.skydoves.pokedex.compose.core.navigation.AppComposeNavigator
+import com.skydoves.pokedex.compose.core.navigation.PokedexScreen
 import com.skydoves.pokedex.compose.navigation.PokedexNavHost
 
 @Composable
-fun PokedexMain(composeNavigator: AppComposeNavigator) {
+fun PokedexMain(composeNavigator: AppComposeNavigator<PokedexScreen>) {
   PokedexTheme {
     val navHostController = rememberNavController()
 

core/database/build.gradle.kts

@@ -18,7 +18,7 @@ plugins {
   id("skydoves.pokedex.android.library")
   id("skydoves.pokedex.android.hilt")
   id("skydoves.pokedex.spotless")
-  id("com.google.devtools.ksp")
+  alias(libs.plugins.ksp)
 }
 
 android {

core/model/build.gradle.kts

@@ -16,9 +16,9 @@
 
 plugins {
   id("skydoves.pokedex.android.library")
-  id("org.jetbrains.kotlin.plugin.serialization")
-  id("kotlin-parcelize")
-  id("com.google.devtools.ksp")
+  alias(libs.plugins.kotlinx.serialization)
+  alias(libs.plugins.kotlin.parcelize)
+  alias(libs.plugins.ksp)
   id("skydoves.pokedex.spotless")
 }
 

core/navigation/build.gradle.kts

@@ -1,7 +1,7 @@
 plugins {
   id("skydoves.pokedex.android.library")
   id("skydoves.pokedex.android.library.compose")
-  id("org.jetbrains.kotlin.plugin.serialization")
+  alias(libs.plugins.kotlinx.serialization)
   id("skydoves.pokedex.android.hilt")
   id("skydoves.pokedex.spotless")
 }
@@ -13,10 +13,9 @@ android {
 dependencies {
   implementation(projects.core.model)
 
+  implementation(libs.androidx.core)
   implementation(libs.kotlinx.coroutines.android)
 
-  implementation(libs.androidx.compose.ui)
-  implementation(libs.androidx.compose.animation)
   api(libs.androidx.navigation.compose)
 
   // json parsing

core/navigation/src/main/kotlin/com/skydoves/pokedex/compose/core/navigation/LocalComposeNavigator.kt

@@ -21,7 +21,7 @@ import androidx.compose.runtime.ProvidableCompositionLocal
 import androidx.compose.runtime.ReadOnlyComposable
 import androidx.compose.runtime.compositionLocalOf
 
-public val LocalComposeNavigator: ProvidableCompositionLocal<AppComposeNavigator> =
+public val LocalComposeNavigator: ProvidableCompositionLocal<AppComposeNavigator<PokedexScreen>> =
   compositionLocalOf {
     error(
       "No AppComposeNavigator provided! " +
@@ -32,7 +32,7 @@ public val LocalComposeNavigator: ProvidableCompositionLocal<AppComposeNavigator
 /**
  * Retrieves the current [AppComposeNavigator] at the call site's position in the hierarchy.
  */
-public val currentComposeNavigator: AppComposeNavigator
+public val currentComposeNavigator: AppComposeNavigator<PokedexScreen>
   @Composable
   @ReadOnlyComposable
   get() = LocalComposeNavigator.current

core/navigation/src/main/kotlin/com/skydoves/pokedex/compose/core/navigation/NavigationCommand.kt

@@ -18,19 +18,20 @@ package com.skydoves.pokedex.compose.core.navigation
 
 import androidx.navigation.NavOptions
 
-sealed class NavigationCommand {
-  data object NavigateUp : NavigationCommand()
+sealed interface NavigationCommand {
+  data object NavigateUp : NavigationCommand
 }
 
-sealed class ComposeNavigationCommand : NavigationCommand() {
-  data class NavigateToRoute(val route: String, val options: NavOptions? = null) :
-    ComposeNavigationCommand()
+sealed interface ComposeNavigationCommand : NavigationCommand {
+  data class NavigateToRoute<T : Any>(val route: T, val options: NavOptions? = null) :
+    ComposeNavigationCommand
 
-  data class NavigateUpWithResult<T>(
+  data class NavigateUpWithResult<R, T : Any>(
     val key: String,
-    val result: T,
-    val route: String? = null,
-  ) : ComposeNavigationCommand()
+    val result: R,
+    val route: T? = null,
+  ) : ComposeNavigationCommand
 
-  data class PopUpToRoute(val route: String, val inclusive: Boolean) : ComposeNavigationCommand()
+  data class PopUpToRoute<T : Any>(val route: T, val inclusive: Boolean) :
+    ComposeNavigationCommand
 }

core/navigation/src/main/kotlin/com/skydoves/pokedex/compose/core/navigation/NavigationModule.kt

@@ -24,11 +24,11 @@ import javax.inject.Singleton
 
 @Module
 @InstallIn(SingletonComponent::class)
-internal abstract class NavigationModule {
+internal interface NavigationModule {
 
   @Binds
   @Singleton
-  abstract fun provideComposeNavigator(
+  fun provideComposeNavigator(
     pokedexComposeNavigator: PokedexComposeNavigator,
-  ): AppComposeNavigator
+  ): AppComposeNavigator<PokedexScreen>
 }

core/navigation/src/main/kotlin/com/skydoves/pokedex/compose/core/navigation/Navigator.kt

@@ -35,12 +35,12 @@ abstract class Navigator {
   }
 }
 
-abstract class AppComposeNavigator : Navigator() {
-  abstract fun navigate(route: String, optionsBuilder: (NavOptionsBuilder.() -> Unit)? = null)
-  abstract fun <T> navigateBackWithResult(key: String, result: T, route: String?)
+abstract class AppComposeNavigator<T : Any> : Navigator() {
+  abstract fun navigate(route: T, optionsBuilder: (NavOptionsBuilder.() -> Unit)? = null)
+  abstract fun <R> navigateBackWithResult(key: String, result: R, route: T?)
 
-  abstract fun popUpTo(route: String, inclusive: Boolean)
-  abstract fun navigateAndClearBackStack(route: String)
+  abstract fun popUpTo(route: T, inclusive: Boolean)
+  abstract fun navigateAndClearBackStack(route: T)
 
   suspend fun handleNavigationCommands(navController: NavController) {
     navigationCommands
@@ -51,24 +51,24 @@ abstract class AppComposeNavigator : Navigator() {
 
   private fun NavController.handleComposeNavigationCommand(navigationCommand: NavigationCommand) {
     when (navigationCommand) {
-      is ComposeNavigationCommand.NavigateToRoute -> {
+      is ComposeNavigationCommand.NavigateToRoute<*> -> {
         navigate(navigationCommand.route, navigationCommand.options)
       }
 
       NavigationCommand.NavigateUp -> navigateUp()
-      is ComposeNavigationCommand.PopUpToRoute -> popBackStack(
+      is ComposeNavigationCommand.PopUpToRoute<*> -> popBackStack(
         navigationCommand.route,
         navigationCommand.inclusive,
       )
 
-      is ComposeNavigationCommand.NavigateUpWithResult<*> -> {
+      is ComposeNavigationCommand.NavigateUpWithResult<*, *> -> {
         navUpWithResult(navigationCommand)
       }
     }
   }
 
   private fun NavController.navUpWithResult(
-    navigationCommand: ComposeNavigationCommand.NavigateUpWithResult<*>,
+    navigationCommand: ComposeNavigationCommand.NavigateUpWithResult<*, *>,
   ) {
     val backStackEntry =
       navigationCommand.route?.let { getBackStackEntry(it) }
@@ -80,8 +80,6 @@ abstract class AppComposeNavigator : Navigator() {
 
     navigationCommand.route?.let {
       popBackStack(it, false)
-    } ?: run {
-      navigateUp()
-    }
+    } ?: navigateUp()
   }
 }

core/navigation/src/main/kotlin/com/skydoves/pokedex/compose/core/navigation/PokedexComposeNavigator.kt

@@ -20,14 +20,14 @@ import androidx.navigation.NavOptionsBuilder
 import androidx.navigation.navOptions
 import javax.inject.Inject
 
-class PokedexComposeNavigator @Inject constructor() : AppComposeNavigator() {
+class PokedexComposeNavigator @Inject constructor() : AppComposeNavigator<PokedexScreen>() {
 
-  override fun navigate(route: String, optionsBuilder: (NavOptionsBuilder.() -> Unit)?) {
+  override fun navigate(route: PokedexScreen, optionsBuilder: (NavOptionsBuilder.() -> Unit)?) {
     val options = optionsBuilder?.let { navOptions(it) }
     navigationCommands.tryEmit(ComposeNavigationCommand.NavigateToRoute(route, options))
   }
 
-  override fun navigateAndClearBackStack(route: String) {
+  override fun navigateAndClearBackStack(route: PokedexScreen) {
     navigationCommands.tryEmit(
       ComposeNavigationCommand.NavigateToRoute(
         route,
@@ -38,11 +38,11 @@ class PokedexComposeNavigator @Inject constructor() : AppComposeNavigator() {
     )
   }
 
-  override fun popUpTo(route: String, inclusive: Boolean) {
+  override fun popUpTo(route: PokedexScreen, inclusive: Boolean) {
     navigationCommands.tryEmit(ComposeNavigationCommand.PopUpToRoute(route, inclusive))
   }
 
-  override fun <T> navigateBackWithResult(key: String, result: T, route: String?) {
+  override fun <R> navigateBackWithResult(key: String, result: R, route: PokedexScreen?) {
     navigationCommands.tryEmit(
       ComposeNavigationCommand.NavigateUpWithResult(
         key = key,

core/navigation/src/main/kotlin/com/skydoves/pokedex/compose/core/navigation/Parcelable.kt → core/navigation/src/main/kotlin/com/skydoves/pokedex/compose/core/navigation/PokedexScreen.kt

@@ -16,14 +16,18 @@
 
 package com.skydoves.pokedex.compose.core.navigation
 
-import android.os.Build
-import android.os.Bundle
-import android.os.Parcelable
+import com.skydoves.pokedex.compose.core.model.Pokemon
+import kotlinx.serialization.Serializable
+import kotlin.reflect.typeOf
 
-inline fun <reified T : Parcelable> Bundle.parcelable(key: String): T? = when {
-  Build.VERSION.SDK_INT >= 33 -> getParcelable(key, T::class.java)
-  else ->
-    @Suppress("DEPRECATION")
-    getParcelable(key)
-      as? T
+sealed interface PokedexScreen {
+  @Serializable
+  data object Home : PokedexScreen
+
+  @Serializable
+  data class Details(val pokemon: Pokemon) : PokedexScreen {
+    companion object {
+      val typeMap = mapOf(typeOf<Pokemon>() to PokemonType)
+    }
+  }
 }