Merge pull request #529 from nimblehq/chore/improve-the-base-navigation

[#552] Improve the base navigation with a "MainNavGraph"

sample-compose/app/src/androidTest/java/co/nimblehq/sample/compose/test/MockUtil.kt

@@ -0,0 +1,21 @@
+package co.nimblehq.sample.compose.test
+
+import co.nimblehq.sample.compose.domain.model.Model
+
+object MockUtil {
+
+    val models = listOf(
+        Model(
+            id = 1,
+            username = "name1",
+        ),
+        Model(
+            id = 2,
+            username = "name2",
+        ),
+        Model(
+            id = 3,
+            username = "name3",
+        ),
+    )
+}

sample-compose/app/src/androidTest/java/co/nimblehq/sample/compose/ui/screens/home/HomeScreenTest.kt → sample-compose/app/src/androidTest/java/co/nimblehq/sample/compose/ui/screens/main/home/HomeScreenTest.kt

@@ -1,22 +1,29 @@
-package co.nimblehq.sample.compose.ui.screens.home
+package co.nimblehq.sample.compose.ui.screens.main.home
 
 import androidx.activity.compose.setContent
-import androidx.compose.ui.test.*
+import androidx.compose.ui.test.assertIsDisplayed
 import androidx.compose.ui.test.junit4.AndroidComposeTestRule
 import androidx.compose.ui.test.junit4.createAndroidComposeRule
+import androidx.compose.ui.test.onNodeWithText
+import androidx.compose.ui.test.performClick
 import androidx.test.ext.junit.rules.ActivityScenarioRule
 import androidx.test.rule.GrantPermissionRule
-import co.nimblehq.sample.compose.domain.model.Model
-import co.nimblehq.sample.compose.domain.usecase.*
+import co.nimblehq.sample.compose.domain.usecase.GetModelsUseCase
+import co.nimblehq.sample.compose.domain.usecase.IsFirstTimeLaunchPreferencesUseCase
+import co.nimblehq.sample.compose.domain.usecase.UpdateFirstTimeLaunchPreferencesUseCase
+import co.nimblehq.sample.compose.test.MockUtil
 import co.nimblehq.sample.compose.test.TestDispatchersProvider
-import co.nimblehq.sample.compose.ui.AppDestination
+import co.nimblehq.sample.compose.ui.base.BaseDestination
 import co.nimblehq.sample.compose.ui.screens.MainActivity
+import co.nimblehq.sample.compose.ui.screens.main.MainDestination
 import co.nimblehq.sample.compose.ui.theme.ComposeTheme
 import io.mockk.every
 import io.mockk.mockk
 import kotlinx.coroutines.flow.flowOf
-import org.junit.*
 import org.junit.Assert.assertEquals
+import org.junit.Before
+import org.junit.Rule
+import org.junit.Test
 
 class HomeScreenTest {
 
@@ -36,13 +43,11 @@ class HomeScreenTest {
     private val mockUpdateFirstTimeLaunchPreferencesUseCase: UpdateFirstTimeLaunchPreferencesUseCase = mockk()
 
     private lateinit var viewModel: HomeViewModel
-    private var expectedAppDestination: AppDestination? = null
+    private var expectedDestination: BaseDestination? = null
 
     @Before
     fun setUp() {
-        every { mockGetModelsUseCase() } returns flowOf(
-            listOf(Model(1), Model(2), Model(3))
-        )
+        every { mockGetModelsUseCase() } returns flowOf(MockUtil.models)
         every { mockIsFirstTimeLaunchPreferencesUseCase() } returns flowOf(false)
 
         viewModel = HomeViewModel(
@@ -69,7 +74,7 @@ class HomeScreenTest {
     fun when_clicking_on_a_list_item__it_navigates_to_Second_screen() = initComposable {
         onNodeWithText("1").performClick()
 
-        assertEquals(expectedAppDestination, AppDestination.Second)
+        assertEquals(expectedDestination, MainDestination.Second)
     }
 
     private fun initComposable(
@@ -79,7 +84,7 @@ class HomeScreenTest {
             ComposeTheme {
                 HomeScreen(
                     viewModel = viewModel,
-                    navigator = { destination -> expectedAppDestination = destination }
+                    navigator = { destination -> expectedDestination = destination }
                 )
             }
         }

sample-compose/app/src/main/java/co/nimblehq/sample/compose/ui/AppDestination.kt

@@ -1,39 +1,10 @@
 package co.nimblehq.sample.compose.ui
 
-import androidx.navigation.NamedNavArgument
-import androidx.navigation.NavType
-import androidx.navigation.navArgument
-import co.nimblehq.sample.compose.ui.models.UiModel
+import co.nimblehq.sample.compose.ui.base.BaseDestination
 
-const val KeyId = "id"
-const val KeyModel = "model"
+sealed class AppDestination {
 
-sealed class AppDestination(val route: String = "") {
+    object RootNavGraph : BaseDestination("rootNavGraph")
 
-    open val arguments: List<NamedNavArgument> = emptyList()
-
-    open var destination: String = route
-
-    open var parcelableArgument: Pair<String, Any?> = "" to null
-
-    object Up : AppDestination()
-
-    object Home : AppDestination("home")
-
-    object Second : AppDestination("second/{$KeyId}") {
-
-        override val arguments = listOf(
-            navArgument(KeyId) { type = NavType.StringType }
-        )
-
-        fun createRoute(id: String) = apply {
-            destination = "second/$id"
-        }
-    }
-
-    object Third : AppDestination("third") {
-        fun addParcel(value: UiModel) = apply {
-            parcelableArgument = KeyModel to value
-        }
-    }
+    object MainNavGraph : BaseDestination("mainNavGraph")
 }

sample-compose/app/src/main/java/co/nimblehq/sample/compose/ui/AppNavGraph.kt

@@ -0,0 +1,55 @@
+package co.nimblehq.sample.compose.ui
+
+import androidx.compose.runtime.Composable
+import androidx.navigation.NavBackStackEntry
+import androidx.navigation.NavDeepLink
+import androidx.navigation.NavGraphBuilder
+import androidx.navigation.NavHostController
+import androidx.navigation.compose.NavHost
+import androidx.navigation.compose.composable
+import co.nimblehq.sample.compose.ui.base.BaseDestination
+import co.nimblehq.sample.compose.ui.screens.main.mainNavGraph
+
+@Composable
+fun AppNavigation(
+    navController: NavHostController,
+) {
+    NavHost(
+        navController = navController,
+        route = AppDestination.RootNavGraph.route,
+        startDestination = AppDestination.MainNavGraph.destination
+    ) {
+        mainNavGraph(navController = navController)
+    }
+}
+
+fun NavGraphBuilder.composable(
+    destination: BaseDestination,
+    deepLinks: List<NavDeepLink> = emptyList(),
+    content: @Composable (NavBackStackEntry) -> Unit,
+) {
+    composable(
+        route = destination.route,
+        arguments = destination.arguments,
+        deepLinks = deepLinks,
+        content = content
+    )
+}
+
+/**
+ * Navigate to provided [BaseDestination] with a Pair of key value String and Data [parcel]
+ * Caution to use this method. This method use savedStateHandle to store the Parcelable data.
+ * When previousBackstackEntry is popped out from navigation stack, savedStateHandle will return null and cannot retrieve data.
+ * eg.Login -> Home, the Login screen will be popped from the back-stack on logging in successfully.
+ */
+fun NavHostController.navigate(destination: BaseDestination, parcel: Pair<String, Any?>? = null) {
+    when (destination) {
+        is BaseDestination.Up -> navigateUp()
+        else -> {
+            parcel?.let { (key, value) ->
+                currentBackStackEntry?.savedStateHandle?.set(key, value)
+            }
+            navigate(route = destination.destination)
+        }
+    }
+}

sample-compose/app/src/main/java/co/nimblehq/sample/compose/ui/base/BaseDestination.kt

@@ -0,0 +1,14 @@
+package co.nimblehq.sample.compose.ui.base
+
+import androidx.navigation.NamedNavArgument
+
+abstract class BaseDestination(val route: String = "") {
+
+    open val arguments: List<NamedNavArgument> = emptyList()
+
+    open var destination: String = route
+
+    open var parcelableArgument: Pair<String, Any?> = "" to null
+
+    object Up : BaseDestination()
+}

sample-compose/app/src/main/java/co/nimblehq/sample/compose/ui/base/BaseViewModel.kt

@@ -2,7 +2,6 @@ package co.nimblehq.sample.compose.ui.base
 
 import androidx.lifecycle.ViewModel
 import androidx.lifecycle.viewModelScope
-import co.nimblehq.sample.compose.ui.AppDestination
 import kotlinx.coroutines.*
 import kotlinx.coroutines.flow.*
 import kotlin.coroutines.CoroutineContext
@@ -19,7 +18,7 @@ abstract class BaseViewModel : ViewModel() {
     protected val _error = MutableSharedFlow<Throwable>()
     val error = _error.asSharedFlow()
 
-    protected val _navigator = MutableSharedFlow<AppDestination>()
+    protected val _navigator = MutableSharedFlow<BaseDestination>()
     val navigator = _navigator.asSharedFlow()
 
     /**

sample-compose/app/src/main/java/co/nimblehq/sample/compose/ui/screens/AppBar.kt → sample-compose/app/src/main/java/co/nimblehq/sample/compose/ui/common/AppBar.kt

@@ -1,4 +1,4 @@
-package co.nimblehq.sample.compose.ui.screens
+package co.nimblehq.sample.compose.ui.common
 
 import androidx.annotation.StringRes
 import androidx.compose.material.Text

sample-compose/app/src/main/java/co/nimblehq/sample/compose/ui/screens/MainActivity.kt

@@ -3,6 +3,7 @@ package co.nimblehq.sample.compose.ui.screens
 import android.os.Bundle
 import androidx.activity.ComponentActivity
 import androidx.activity.compose.setContent
+import androidx.navigation.compose.rememberNavController
 import co.nimblehq.sample.compose.ui.AppNavigation
 import co.nimblehq.sample.compose.ui.theme.ComposeTheme
 import dagger.hilt.android.AndroidEntryPoint
@@ -14,7 +15,7 @@ class MainActivity : ComponentActivity() {
         super.onCreate(savedInstanceState)
         setContent {
             ComposeTheme {
-                AppNavigation()
+                AppNavigation(navController = rememberNavController())
             }
         }
     }

sample-compose/app/src/main/java/co/nimblehq/sample/compose/ui/screens/main/MainDestination.kt

@@ -0,0 +1,31 @@
+package co.nimblehq.sample.compose.ui.screens.main
+
+import androidx.navigation.NavType
+import androidx.navigation.navArgument
+import co.nimblehq.sample.compose.ui.base.BaseDestination
+import co.nimblehq.sample.compose.ui.models.UiModel
+
+const val KeyId = "id"
+const val KeyModel = "model"
+
+sealed class MainDestination {
+
+    object Home : BaseDestination("home")
+
+    object Second : BaseDestination("second/{$KeyId}") {
+
+        override val arguments = listOf(
+            navArgument(KeyId) { type = NavType.StringType }
+        )
+
+        fun createRoute(id: String) = apply {
+            destination = "second/$id"
+        }
+    }
+
+    object Third : BaseDestination("third") {
+        fun addParcel(value: UiModel) = apply {
+            parcelableArgument = KeyModel to value
+        }
+    }
+}