[Android 从零到一] Navigation 多模块导航与深链治理：让页面跳转可维护、可追踪

findNavController().navigate(
    HomeFragmentDirections.actionHomeToDetail(articleId)
)

sealed interface AppRoute {
    data class ArticleDetail(val articleId: Long) : AppRoute
    data class UserProfile(val userId: String) : AppRoute
    data class WebPage(val url: String) : AppRoute
}

interface AppNavigator {
    fun navigate(route: AppRoute): NavigationResult
}

sealed interface NavigationResult {
    data object Success : NavigationResult
    data class Rejected(val reason: String) : NavigationResult
}

val result = navigator.navigate(AppRoute.ArticleDetail(articleId = 1024L))

class NavControllerAppNavigator(
    private val navControllerProvider: () -> NavController
) : AppNavigator {

    override fun navigate(route: AppRoute): NavigationResult {
        val controller = navControllerProvider()

        return runCatching {
            when (route) {
                is AppRoute.ArticleDetail -> controller.navigate(
                    Uri.parse("myapp://article/${route.articleId}")
                )
                is AppRoute.UserProfile -> controller.navigate(
                    Uri.parse("myapp://user/${route.userId}")
                )
                is AppRoute.WebPage -> controller.navigate(
                    R.id.webFragment,
                    bundleOf("url" to route.url)
                )
            }
            NavigationResult.Success
        }.getOrElse { error ->
            NavigationResult.Rejected(error.message ?: "unknown navigation error")
        }
    }
}

<fragment
    android:id="@+id/articleDetailFragment"
    android:name="com.example.article.ArticleDetailFragment">

    <argument
        android:name="articleId"
        app:argType="long" />

    <deepLink app:uri="myapp://article/{articleId}" />
</fragment>

<navigation
    android:id="@+id/app_graph"
    app:startDestination="@id/home_graph">

    <include app:graph="@navigation/home_graph" />
    <include app:graph="@navigation/article_graph" />
    <include app:graph="@navigation/profile_graph" />
</navigation>

class DeepLinkParser {
    fun parse(uri: Uri): AppRoute? {
        if (uri.scheme != "https" || uri.host != "www.example.com") return null

        val segments = uri.pathSegments
        return when {
            segments.size == 2 && segments[0] == "article" -> {
                val id = segments[1].toLongOrNull() ?: return null
                if (id <= 0) null else AppRoute.ArticleDetail(id)
            }
            segments.size == 2 && segments[0] == "user" -> {
                val userId = segments[1].takeIf { it.matches(Regex("[A-Za-z0-9_-]{1,64}")) }
                userId?.let(AppRoute::UserProfile)
            }
            else -> null
        }
    }
}

<intent-filter android:autoVerify="true">
    <action android:name="android.intent.action.VIEW" />
    <category android:name="android.intent.category.DEFAULT" />
    <category android:name="android.intent.category.BROWSABLE" />
    <data
        android:scheme="https"
        android:host="www.example.com"
        android:pathPrefix="/article" />
</intent-filter>

fun interface RouteInterceptor {
    fun intercept(route: AppRoute): AppRoute
}

class LoginInterceptor(
    private val session: UserSession,
    private val pendingRouteStore: PendingRouteStore
) : RouteInterceptor {

    override fun intercept(route: AppRoute): AppRoute {
        val requiresLogin = route is AppRoute.UserProfile
        if (!requiresLogin || session.isLoggedIn) return route

        pendingRouteStore.save(route)
        return AppRoute.Login
    }
}

val options = navOptions {
    launchSingleTop = true
    restoreState = true
}

if (navController.currentDestination?.id != R.id.articleDetailFragment) {
    navController.navigate(uri, options)
}

data class NavigationEvent(
    val source: String,
    val routeName: String,
    val result: String,
    val currentDestination: String?,
    val durationMs: Long
)

class DeepLinkParserTest {
    private val parser = DeepLinkParser()

    @Test
    fun validArticleLink_isParsed() {
        val route = parser.parse(Uri.parse("https://www.example.com/article/1024"))
        assertEquals(AppRoute.ArticleDetail(1024L), route)
    }

    @Test
    fun invalidArticleId_isRejected() {
        val route = parser.parse(Uri.parse("https://www.example.com/article/not-a-number"))
        assertNull(route)
    }

    @Test
    fun unknownHost_isRejected() {
        val route = parser.parse(Uri.parse("https://evil.example/article/1024"))
        assertNull(route)
    }
}