refactor(android): revamp the user interactions of tablet UI and cleanup code

android/src/main/kotlin/dev/msfjarvis/claw/android/ui/ext.kt

@@ -94,7 +94,7 @@ fun TwoPaneLayoutPostActions(
 
     override fun viewComments(postId: String) {
       viewModel.markPostAsRead(postId)
-      setSelectedPost(postId) // Update selectedPostId
+      setSelectedPost(postId)
     }
 
     override fun viewCommentsPage(post: UIPost) {

android/src/main/kotlin/dev/msfjarvis/claw/android/ui/lists/NetworkPosts.kt

@@ -7,7 +7,6 @@
 package dev.msfjarvis.claw.android.ui.lists
 
 import androidx.activity.compose.ReportDrawnWhen
-import androidx.compose.foundation.clickable
 import androidx.compose.foundation.layout.PaddingValues
 import androidx.compose.foundation.layout.fillMaxSize
 import androidx.compose.foundation.layout.fillMaxWidth
@@ -51,7 +50,6 @@ fun NetworkPosts(
   postActions: PostActions,
   contentPadding: PaddingValues,
   modifier: Modifier = Modifier,
-  onPostClick: (String) -> Unit,
 ) {
   ReportDrawnWhen { lazyPagingItems.itemCount > 0 }
   val refreshLoadState by rememberUpdatedState(lazyPagingItems.loadState.refresh)
@@ -84,14 +82,7 @@ fun NetworkPosts(
         ) { index ->
           val item = lazyPagingItems[index]
           if (item != null) {
-            LobstersListItem(
-              item = item,
-              postActions = postActions,
-              modifier =
-                Modifier.clickable {
-                  onPostClick(item.shortId) // Trigger the click listener
-                },
-            )
+            LobstersListItem(item = item, postActions = postActions)
             HorizontalDivider()
           }
         }
@@ -121,7 +112,6 @@ private fun ListPreview() {
       listState = rememberLazyListState(),
       postActions = TEST_POST_ACTIONS,
       contentPadding = PaddingValues(),
-      onPostClick = {},
     )
   }
 }

android/src/main/kotlin/dev/msfjarvis/claw/android/ui/lists/NetworkPostsforTwoPaneLayout.kt

@@ -1,127 +0,0 @@
-/*
- * Copyright © 2021-2024 Harsh Shandilya.
- * Use of this source code is governed by an MIT-style
- * license that can be found in the LICENSE file or at
- * https://opensource.org/licenses/MIT.
- */
-package dev.msfjarvis.claw.android.ui.lists
-
-import androidx.activity.compose.ReportDrawnWhen
-import androidx.compose.foundation.clickable
-import androidx.compose.foundation.layout.PaddingValues
-import androidx.compose.foundation.layout.fillMaxSize
-import androidx.compose.foundation.layout.fillMaxWidth
-import androidx.compose.foundation.layout.padding
-import androidx.compose.foundation.layout.wrapContentWidth
-import androidx.compose.foundation.lazy.LazyColumn
-import androidx.compose.foundation.lazy.LazyListState
-import androidx.compose.foundation.lazy.rememberLazyListState
-import androidx.compose.material3.ExperimentalMaterial3Api
-import androidx.compose.material3.HorizontalDivider
-import androidx.compose.material3.pulltorefresh.PullToRefreshBox
-import androidx.compose.material3.pulltorefresh.PullToRefreshDefaults
-import androidx.compose.material3.pulltorefresh.rememberPullToRefreshState
-import androidx.compose.runtime.Composable
-import androidx.compose.runtime.getValue
-import androidx.compose.runtime.rememberUpdatedState
-import androidx.compose.ui.Alignment
-import androidx.compose.ui.Modifier
-import androidx.compose.ui.unit.dp
-import androidx.paging.LoadState
-import androidx.paging.PagingData
-import androidx.paging.compose.LazyPagingItems
-import androidx.paging.compose.collectAsLazyPagingItems
-import androidx.paging.compose.itemContentType
-import androidx.paging.compose.itemKey
-import dev.msfjarvis.claw.common.posts.PostActions
-import dev.msfjarvis.claw.common.posts.TEST_POST
-import dev.msfjarvis.claw.common.posts.TEST_POST_ACTIONS
-import dev.msfjarvis.claw.common.theme.LobstersTheme
-import dev.msfjarvis.claw.common.ui.NetworkError
-import dev.msfjarvis.claw.common.ui.ProgressBar
-import dev.msfjarvis.claw.common.ui.preview.DevicePreviews
-import dev.msfjarvis.claw.model.UIPost
-import kotlinx.coroutines.flow.MutableStateFlow
-
-@OptIn(ExperimentalMaterial3Api::class)
-@Composable
-fun NetworkPostsForTwoPaneLayout(
-  lazyPagingItems: LazyPagingItems<UIPost>,
-  listState: LazyListState,
-  postActions: PostActions,
-  contentPadding: PaddingValues,
-  modifier: Modifier = Modifier,
-  onPostClick: (String) -> Unit,
-) {
-  ReportDrawnWhen { lazyPagingItems.itemCount > 0 }
-  val refreshLoadState by rememberUpdatedState(lazyPagingItems.loadState.refresh)
-  val state = rememberPullToRefreshState()
-  PullToRefreshBox(
-    modifier = modifier.fillMaxSize(),
-    isRefreshing = refreshLoadState == LoadState.Loading,
-    state = state,
-    onRefresh = { lazyPagingItems.refresh() },
-    indicator = {
-      PullToRefreshDefaults.Indicator(
-        state = state,
-        isRefreshing = refreshLoadState == LoadState.Loading,
-        modifier = Modifier.align(Alignment.TopCenter).padding(contentPadding),
-      )
-    },
-  ) {
-    if (lazyPagingItems.itemCount == 0 && refreshLoadState is LoadState.Error) {
-      NetworkError(
-        label = "Failed to load posts",
-        error = (refreshLoadState as LoadState.Error).error,
-        modifier = Modifier.align(Alignment.Center),
-      )
-    } else {
-      LazyColumn(contentPadding = contentPadding, state = listState) {
-        items(
-          count = lazyPagingItems.itemCount,
-          key = lazyPagingItems.itemKey { it.shortId },
-          contentType = lazyPagingItems.itemContentType { "LobstersItem" },
-        ) { index ->
-          val item = lazyPagingItems[index]
-          if (item != null) {
-            LobstersListItem(
-              item = item,
-              postActions = postActions,
-              modifier =
-                Modifier.clickable {
-                  onPostClick(item.shortId) // Trigger the click listener)
-                },
-            )
-            HorizontalDivider()
-          }
-        }
-        if (lazyPagingItems.loadState.append == LoadState.Loading) {
-          item(key = "progressbar") {
-            ProgressBar(
-              modifier =
-                Modifier.fillMaxWidth()
-                  .wrapContentWidth(Alignment.CenterHorizontally)
-                  .padding(vertical = 16.dp)
-            )
-          }
-        }
-      }
-    }
-  }
-}
-
-@DevicePreviews
-@Composable
-private fun ListPreview() {
-  val items = List(20) { TEST_POST.copy(shortId = "${TEST_POST.shortId}${it}") }
-  val flow = MutableStateFlow(PagingData.from(items))
-  LobstersTheme {
-    NetworkPostsForTwoPaneLayout(
-      lazyPagingItems = flow.collectAsLazyPagingItems(),
-      listState = rememberLazyListState(),
-      postActions = TEST_POST_ACTIONS,
-      contentPadding = PaddingValues(),
-      onPostClick = {},
-    )
-  }
-}

android/src/main/kotlin/dev/msfjarvis/claw/android/ui/lists/SearchList.kt

@@ -33,7 +33,6 @@ fun SearchList(
   setSearchQuery: (String) -> Unit,
   contentPadding: PaddingValues,
   modifier: Modifier = Modifier,
-  onPostClick: (String) -> Unit,
 ) {
   val triggerSearch = { query: String ->
     setSearchQuery(query)
@@ -54,7 +53,6 @@ fun SearchList(
       listState = listState,
       postActions = postActions,
       contentPadding = contentPadding,
-      onPostClick = onPostClick,
     )
   }
 }

android/src/main/kotlin/dev/msfjarvis/claw/android/ui/screens/LobstersPostsScreen.kt

@@ -39,7 +39,6 @@ import androidx.compose.runtime.LaunchedEffect
 import androidx.compose.runtime.getValue
 import androidx.compose.runtime.remember
 import androidx.compose.runtime.rememberCoroutineScope
-import androidx.compose.ui.ExperimentalComposeUiApi
 import androidx.compose.ui.Modifier
 import androidx.compose.ui.draw.shadow
 import androidx.compose.ui.platform.LocalContext
@@ -90,7 +89,7 @@ import kotlinx.collections.immutable.persistentMapOf
 import kotlinx.collections.immutable.toPersistentList
 import kotlinx.coroutines.launch
 
-@OptIn(ExperimentalComposeUiApi::class, ExperimentalMaterial3Api::class)
+@OptIn(ExperimentalMaterial3Api::class)
 @Composable
 fun LobstersPostsScreen(
   urlLauncher: UrlLauncher,
@@ -238,7 +237,6 @@ fun LobstersPostsScreen(
             listState = hottestListState,
             postActions = postActions,
             contentPadding = contentPadding,
-            onPostClick = { postId -> navController.navigate(Comments(postId)) },
           )
         }
         composable<Newest> {
@@ -248,7 +246,6 @@ fun LobstersPostsScreen(
             listState = newestListState,
             postActions = postActions,
             contentPadding = contentPadding,
-            onPostClick = { postId -> navController.navigate(Comments(postId)) },
           )
         }
         composable<Saved> {

android/src/main/kotlin/dev/msfjarvis/claw/android/ui/screens/SearchScreen.kt

@@ -43,7 +43,6 @@ fun SearchScreen(
   val listState = rememberLazyListState()
   val searchResults = viewModel.searchResults.collectAsLazyPagingItems()
 
-  val onPostClick: (String) -> Unit = { postId -> navController.navigate("comments/$postId") }
   Scaffold(modifier = modifier) { contentPadding ->
     NavHost(navController = navController, startDestination = Search) {
       composable<Search> {
@@ -55,7 +54,6 @@ fun SearchScreen(
           searchQuery = viewModel.searchQuery,
           contentPadding = contentPadding,
           setSearchQuery = { query -> viewModel.searchQuery = query },
-          onPostClick = onPostClick,
         )
       }
       composable<Comments> { backStackEntry ->

android/src/main/kotlin/dev/msfjarvis/claw/android/ui/screens/TwoPaneLayout.kt

@@ -4,8 +4,11 @@
  * license that can be found in the LICENSE file or at
  * https://opensource.org/licenses/MIT.
  */
+@file:OptIn(ExperimentalMaterial3AdaptiveApi::class)
+
 package dev.msfjarvis.claw.android.ui.screens
 
+import androidx.activity.compose.BackHandler
 import androidx.compose.foundation.layout.Box
 import androidx.compose.foundation.layout.PaddingValues
 import androidx.compose.foundation.layout.fillMaxSize
@@ -18,13 +21,16 @@ import androidx.compose.material3.Scaffold
 import androidx.compose.material3.Text
 import androidx.compose.material3.TopAppBar
 import androidx.compose.material3.adaptive.ExperimentalMaterial3AdaptiveApi
-import androidx.compose.material3.adaptive.navigation.NavigableListDetailPaneScaffold
+import androidx.compose.material3.adaptive.layout.AnimatedPane
+import androidx.compose.material3.adaptive.layout.ListDetailPaneScaffold
+import androidx.compose.material3.adaptive.layout.ListDetailPaneScaffoldRole
+import androidx.compose.material3.adaptive.layout.PaneAdaptedValue
+import androidx.compose.material3.adaptive.navigation.BackNavigationBehavior
+import androidx.compose.material3.adaptive.navigation.ThreePaneScaffoldNavigator
 import androidx.compose.material3.adaptive.navigation.rememberListDetailPaneScaffoldNavigator
 import androidx.compose.runtime.Composable
-import androidx.compose.runtime.getValue
-import androidx.compose.runtime.mutableStateOf
 import androidx.compose.runtime.remember
-import androidx.compose.runtime.setValue
+import androidx.compose.runtime.rememberCoroutineScope
 import androidx.compose.ui.Alignment
 import androidx.compose.ui.Modifier
 import androidx.compose.ui.platform.LocalContext
@@ -37,14 +43,22 @@ import androidx.paging.compose.collectAsLazyPagingItems
 import com.deliveryhero.whetstone.compose.injectedViewModel
 import dev.msfjarvis.claw.android.R
 import dev.msfjarvis.claw.android.ui.TwoPaneLayoutPostActions
-import dev.msfjarvis.claw.android.ui.lists.NetworkPostsForTwoPaneLayout
+import dev.msfjarvis.claw.android.ui.lists.NetworkPosts
+import dev.msfjarvis.claw.android.ui.navigation.Comments
 import dev.msfjarvis.claw.android.ui.navigation.User
 import dev.msfjarvis.claw.android.viewmodel.ClawViewModel
 import dev.msfjarvis.claw.common.comments.CommentsPage
 import dev.msfjarvis.claw.common.comments.HTMLConverter
 import dev.msfjarvis.claw.common.urllauncher.UrlLauncher
+import kotlinx.coroutines.launch
 
-@OptIn(ExperimentalMaterial3AdaptiveApi::class, ExperimentalMaterial3Api::class)
+private fun ThreePaneScaffoldNavigator<*>.isListExpanded() =
+  scaffoldValue[ListDetailPaneScaffoldRole.List] == PaneAdaptedValue.Expanded
+
+private fun ThreePaneScaffoldNavigator<*>.isDetailExpanded() =
+  scaffoldValue[ListDetailPaneScaffoldRole.Detail] == PaneAdaptedValue.Expanded
+
+@OptIn(ExperimentalMaterial3Api::class)
 @Composable
 fun TwoPaneLayout(
   urlLauncher: UrlLauncher,
@@ -52,23 +66,30 @@ fun TwoPaneLayout(
   modifier: Modifier = Modifier,
   viewModel: ClawViewModel = injectedViewModel(),
 ) {
-
   val context = LocalContext.current
   val hottestListState = rememberLazyListState()
   val navController = rememberNavController()
-
-  // Track the selected postId as a mutable state
-  var selectedPostId by remember { mutableStateOf<String?>(null) }
-
-  // Initialize postActions with selectedPostId as a mutable state
-  val postActions = remember {
-    TwoPaneLayoutPostActions(context, urlLauncher, viewModel, { selectedPostId = it })
-  }
-
+  val coroutineScope = rememberCoroutineScope()
   val hottestPosts = viewModel.hottestPosts.collectAsLazyPagingItems()
+  val navigator = rememberListDetailPaneScaffoldNavigator<Comments>()
+  val backBehavior =
+    if (navigator.isListExpanded() && navigator.isDetailExpanded()) {
+      BackNavigationBehavior.PopUntilContentChange
+    } else {
+      BackNavigationBehavior.PopUntilScaffoldValueChange
+    }
 
-  // Navigator state
-  val navigator = rememberListDetailPaneScaffoldNavigator<Any>()
+  val postActions = remember {
+    TwoPaneLayoutPostActions(context, urlLauncher, viewModel) {
+      coroutineScope.launch {
+        navigator.navigateTo(pane = ListDetailPaneScaffoldRole.Detail, contentKey = Comments(it))
+      }
+    }
+  }
+
+  BackHandler(navigator.canNavigateBack(backBehavior)) {
+    coroutineScope.launch { navigator.navigateBack(backBehavior) }
+  }
 
   Scaffold(
     topBar = {
@@ -84,40 +105,46 @@ fun TwoPaneLayout(
       )
     },
     content = { paddingValues ->
-      NavigableListDetailPaneScaffold(
+      ListDetailPaneScaffold(
         modifier = modifier.padding(paddingValues),
-        navigator = navigator,
+        directive = navigator.scaffoldDirective,
+        value = navigator.scaffoldValue,
         listPane = {
-          NetworkPostsForTwoPaneLayout(
-            lazyPagingItems = hottestPosts,
-            listState = hottestListState,
-            postActions = postActions,
-            contentPadding = PaddingValues(),
-            modifier = Modifier.fillMaxSize(),
-          ) { postId ->
-            selectedPostId = postId // Update selectedPostId on click
-          }
-        },
-        detailPane = {
-          selectedPostId?.let { postId ->
-            CommentsPage(
-              postId = postId,
+          AnimatedPane {
+            NetworkPosts(
+              lazyPagingItems = hottestPosts,
+              listState = hottestListState,
               postActions = postActions,
-              htmlConverter = htmlConverter,
-              getSeenComments = viewModel::getSeenComments,
-              markSeenComments = viewModel::markSeenComments,
-              openUserProfile = { navController.navigate(User(it)) },
               contentPadding = PaddingValues(),
               modifier = Modifier.fillMaxSize(),
             )
           }
-            ?: Box(Modifier.fillMaxSize()) {
-              // Placeholder when no post is selected
-              Text(
-                text = "Select a post to view comments",
-                modifier = Modifier.align(Alignment.Center),
-              )
+        },
+        detailPane = {
+          AnimatedPane {
+            when (val contentKey = navigator.currentDestination?.contentKey) {
+              null -> {
+                Box(Modifier.fillMaxSize()) {
+                  Text(
+                    text = "Select a post to view comments",
+                    modifier = Modifier.align(Alignment.Center),
+                  )
+                }
+              }
+              else -> {
+                CommentsPage(
+                  postId = contentKey.postId,
+                  postActions = postActions,
+                  htmlConverter = htmlConverter,
+                  getSeenComments = viewModel::getSeenComments,
+                  markSeenComments = viewModel::markSeenComments,
+                  openUserProfile = { navController.navigate(User(it)) },
+                  contentPadding = PaddingValues(),
+                  modifier = Modifier.fillMaxSize(),
+                )
+              }
             }
+          }
         },
       )
     },

android/src/screenshotTest/kotlin/dev/msfjarvis/claw/android/ui/lists/NetworkPostsTest.kt

@@ -31,7 +31,6 @@ class NetworkPostsTest {
         listState = rememberLazyListState(),
         postActions = TEST_POST_ACTIONS,
         contentPadding = PaddingValues(),
-        onPostClick = {},
       )
     }
   }