fix: resolve channel detail black screen and navigation issues

- Change Routes.ChannelDetail to accept channelId parameter
- Update ChannelDetailScreen to fetch channel on initialization
- Replace early return with loading state when channel is null
- Navigate directly to detail screen with channelId
- Remove intermediate navigation through list screen
- Fix predictive back gesture by eliminating blank composable state

Fixes #668

Co-authored-by: Ovi Trif <[email protected]>

Author: github-actions[bot]

app/src/main/java/to/bitkit/ui/ContentView.kt

@@ -1204,9 +1204,11 @@ private fun NavGraphBuilder.lightningConnections(
         composableWithDefaultTransitions<Routes.ChannelDetail> {
             val parentEntry = remember(it) { navController.getBackStackEntry(Routes.ConnectionsNav) }
             val viewModel = hiltViewModel<LightningConnectionsViewModel>(parentEntry)
+            val route = it.toRoute<Routes.ChannelDetail>()
             ChannelDetailScreen(
                 navController = navController,
                 viewModel = viewModel,
+                channelId = route.channelId,
             )
         }
         composableWithDefaultTransitions<Routes.CloseConnection> {
@@ -1836,7 +1838,7 @@ sealed interface Routes {
     data object LightningConnections : Routes
 
     @Serializable
-    data object ChannelDetail : Routes
+    data class ChannelDetail(val channelId: String) : Routes
 
     @Serializable
     data object CloseConnection : Routes

app/src/main/java/to/bitkit/ui/settings/lightning/ChannelDetailScreen.kt

@@ -85,19 +85,42 @@ import java.util.Locale
 fun ChannelDetailScreen(
     navController: NavController,
     viewModel: LightningConnectionsViewModel,
+    channelId: String,
 ) {
     val context = LocalContext.current
     val app = appViewModel ?: return
     val wallet = walletViewModel ?: return
 
+    LaunchedEffect(channelId) {
+        viewModel.findAndSelectChannel(channelId)
+    }
+
     val selectedChannel by viewModel.selectedChannel.collectAsStateWithLifecycle()
-    val channel = selectedChannel ?: return
+    val channel = selectedChannel
 
     val uiState by viewModel.uiState.collectAsStateWithLifecycle()
     val paidOrders by viewModel.blocktankRepo.blocktankState.collectAsStateWithLifecycle()
+    val lightningState by wallet.lightningState.collectAsStateWithLifecycle()
+
+    if (channel == null) {
+        Content(
+            channel = null,
+            blocktankOrders = emptyList(),
+            cjitEntries = emptyList(),
+            txTime = null,
+            isRefreshing = false,
+            isClosedChannel = false,
+            onBack = { navController.popBackStack() },
+            onRefresh = {},
+            onCopyText = {},
+            onOpenUrl = {},
+            onSupport = {},
+            onCloseConnection = {},
+        )
+        return
+    }
 
     val isClosedChannel = uiState.closedChannels.any { it.details.channelId == channel.details.channelId }
-    val lightningState by wallet.lightningState.collectAsStateWithLifecycle()
 
     // Fetch transaction details for funding transaction if available
     LaunchedEffect(channel.details.fundingTxo?.txid) {
@@ -108,8 +131,8 @@ fun ChannelDetailScreen(
 
     // Fetch activity timestamp for transfer activity with matching channel ID
     LaunchedEffect(channel.details.channelId) {
-        channel.details.channelId?.let { channelId ->
-            viewModel.fetchActivityTimestamp(channelId)
+        channel.details.channelId.let { id ->
+            viewModel.fetchActivityTimestamp(id)
         }
     }
 
@@ -148,7 +171,7 @@ fun ChannelDetailScreen(
 @Suppress("CyclomaticComplexMethod")
 @Composable
 private fun Content(
-    channel: ChannelUi,
+    channel: ChannelUi?,
     blocktankOrders: List<IBtOrder> = emptyList(),
     cjitEntries: List<IcJitEntry> = emptyList(),
     txTime: ULong? = null,
@@ -161,6 +184,24 @@ private fun Content(
     onSupport: (Any) -> Unit = {},
     onCloseConnection: () -> Unit = {},
 ) {
+    ScreenColumn {
+        AppTopBar(
+            titleText = channel?.name ?: "",
+            onBackClick = onBack,
+            actions = { DrawerNavIcon() },
+        )
+
+        if (channel == null) {
+            Box(
+                modifier = Modifier
+                    .fillMaxSize()
+                    .padding(16.dp),
+                contentAlignment = Alignment.Center
+            ) {
+                CaptionB(text = stringResource(R.string.common__loading))
+            }
+            return@ScreenColumn
+        }
     // Check if the channel was opened via CJIT
     val cjitEntry = cjitEntries.find { entry ->
         entry.channel?.fundingTx?.id == channel.details.fundingTxo?.txid
@@ -184,13 +225,6 @@ private fun Content(
     val remoteBalance = (channel.details.inboundCapacityMsat / 1000u).toLong()
     val reserveBalance = (channel.details.unspendablePunishmentReserve ?: 0u).toLong()
 
-    ScreenColumn {
-        AppTopBar(
-            titleText = channel.name,
-            onBackClick = onBack,
-            actions = { DrawerNavIcon() },
-        )
-
         PullToRefreshBox(
             isRefreshing = isRefreshing,
             onRefresh = onRefresh,

app/src/main/java/to/bitkit/ui/settings/lightning/LightningConnectionsScreen.kt

@@ -88,18 +88,13 @@ fun LightningConnectionsScreen(
         viewModel.refreshObservedState()
         viewModel.clearSelectedChannel()
         viewModel.clearTransactionDetails()
-    }
 
-    LaunchedEffect(navController.currentBackStackEntry) {
         val selectedChannelId = navController.previousBackStackEntry?.savedStateHandle?.get<String>("selectedChannelId")
-        if (selectedChannelId == null) return@LaunchedEffect
-
-        navController.previousBackStackEntry?.savedStateHandle?.remove<String>("selectedChannelId")
-        delay(CHANNEL_SELECTION_DELAY_MS)
-        if (viewModel.findAndSelectChannel(selectedChannelId)) {
-            navController.navigate(Routes.ChannelDetail) {
+        if (selectedChannelId != null) {
+            navController.previousBackStackEntry?.savedStateHandle?.remove<String>("selectedChannelId")
+            delay(CHANNEL_SELECTION_DELAY_MS)
+            navController.navigate(Routes.ChannelDetail(selectedChannelId)) {
                 launchSingleTop = true
-                popUpTo(Routes.ConnectionsNav) { inclusive = false }
             }
         }
     }
@@ -112,8 +107,7 @@ fun LightningConnectionsScreen(
             viewModel.zipLogsForSharing { uri -> context.shareZipFile(uri) }
         },
         onClickChannel = { channelUi ->
-            viewModel.setSelectedChannel(channelUi)
-            navController.navigate(Routes.ChannelDetail)
+            navController.navigate(Routes.ChannelDetail(channelUi.details.channelId))
         },
         onRefresh = {
             viewModel.onPullToRefresh()