Bugfix: Chats not loading on tablet layout

feature/metis/conversation/src/main/kotlin/de/tum/informatics/www1/artemis/native_app/feature/metis/conversation/ui/ConversationChatListScreen.kt

@@ -95,6 +95,10 @@ internal fun ConversationChatListScreen(
     val posts: LazyPagingItems<ChatListItem> =
         viewModel.chatListUseCase.postPagingData.collectAsLazyPagingItems()
 
+    LaunchedEffect(courseId, conversationId) {
+        chatListState.scrollToItem(0)
+    }
+
     ConversationChatListScreen(
         modifier = modifier,
         courseId = courseId,

feature/metis/conversation/src/main/kotlin/de/tum/informatics/www1/artemis/native_app/feature/metis/conversation/ui/ConversationScreen.kt

@@ -1,36 +1,27 @@
 package de.tum.informatics.www1.artemis.native_app.feature.metis.conversation.ui
 
 import androidx.compose.animation.AnimatedContent
-import androidx.compose.animation.AnimatedVisibility
 import androidx.compose.animation.SizeTransform
 import androidx.compose.foundation.layout.Arrangement
 import androidx.compose.foundation.layout.Box
 import androidx.compose.foundation.layout.Row
 import androidx.compose.foundation.layout.fillMaxHeight
 import androidx.compose.foundation.layout.fillMaxSize
-import androidx.compose.foundation.layout.widthIn
 import androidx.compose.material3.VerticalDivider
 import androidx.compose.material3.windowsizeclass.WindowWidthSizeClass
 import androidx.compose.runtime.Composable
-import androidx.compose.runtime.DisposableEffect
 import androidx.compose.runtime.LaunchedEffect
 import androidx.compose.runtime.getValue
 import androidx.compose.runtime.mutableStateOf
 import androidx.compose.runtime.remember
-import androidx.compose.runtime.setValue
 import androidx.compose.ui.Modifier
 import androidx.compose.ui.unit.dp
-import androidx.lifecycle.ViewModelStore
-import androidx.lifecycle.ViewModelStoreOwner
 import de.tum.informatics.www1.artemis.native_app.core.ui.getWindowSizeClass
 import de.tum.informatics.www1.artemis.native_app.core.ui.navigation.DefaultTransition
 import de.tum.informatics.www1.artemis.native_app.feature.metis.shared.content.StandalonePostId
 import org.koin.androidx.compose.koinViewModel
 import org.koin.core.parameter.parametersOf
 
-private const val ConversationOverviewMaxWeight = 0.3f
-private val ConversationOverviewMaxWidth = 600.dp
-
 /**
  * Displays a conversation. Uses [ConversationChatListScreen] and [ConversationThreadScreen] to show the conversations.
  * @param conversationId the conversation that should be displayed
@@ -49,138 +40,97 @@ fun ConversationScreen(
     onNavigateToSettings: () -> Unit,
     conversationsOverview: @Composable (Modifier) -> Unit
 ) {
-    val store = remember { ViewModelStore() }
-
-    val owner = remember(store) {
-        object : ViewModelStoreOwner {
-            override val viewModelStore: ViewModelStore = store
-        }
-    }
-
-    DisposableEffect(courseId, conversationId) {
-        onDispose {
-            store.clear()
-        }
-    }
-
     val viewModel: ConversationViewModel =
         koinViewModel(
             key = "$courseId|$conversationId",
-            viewModelStoreOwner = owner
-        ) { parametersOf(courseId, conversationId, threadPostId) }
+    ) { parametersOf(courseId, conversationId, threadPostId) }
 
     LaunchedEffect(threadPostId, viewModel) {
         viewModel.updateOpenedThread(threadPostId)
     }
 
-    val widthSizeClass = getWindowSizeClass().widthSizeClass
-    var showThread by remember { mutableStateOf(threadPostId != null) }
-
-    val onNavigateUp = {
-        onCloseThread()
-        showThread = false
+    val showThread by remember(threadPostId) {
+        mutableStateOf(threadPostId != null)
     }
-    val onClickViewPost = { clientPostId: StandalonePostId ->
-        onOpenThread(clientPostId)
-        showThread = true
+
+    WindowSizeAwareTwoColumnLayout(
+        modifier = modifier,
+        optionalColumn = conversationsOverview,
+    ) { innerModifier ->
+        AnimatedContent(
+            modifier = innerModifier,
+            targetState = showThread,
+            transitionSpec = {
+                if (targetState) {
+                    DefaultTransition.navigateForward
+                } else {
+                    DefaultTransition.navigateBack
+                }.using(
+                    SizeTransform(clip = false)
+                )
+            },
+            label = "ConversationScreen chatList thread navigation animation"
+        ) { _showThread ->
+            if (_showThread) {
+                ConversationThreadScreen(
+                    modifier = Modifier.fillMaxSize(),
+                    viewModel = viewModel,
+                    onNavigateUp = onCloseThread
+                )
+            } else {
+                ConversationChatListScreen(
+                    modifier = Modifier.fillMaxSize(),
+                    viewModel = viewModel,
+                    courseId = courseId,
+                    conversationId = conversationId,
+                    onNavigateBack = onCloseConversation,
+                    onNavigateToSettings = onNavigateToSettings,
+                    onClickViewPost = onOpenThread
+                )
+            }
+        }
     }
+}
+
+
+@Composable
+fun WindowSizeAwareTwoColumnLayout(
+    modifier: Modifier = Modifier,
+    optionalColumnWeight: Float = 1f,
+    priorityColumnWeight: Float = 2f,
+    optionalColumn: @Composable (Modifier) -> Unit,
+    priorityColumn: @Composable (Modifier) -> Unit
+) {
+    val widthSizeClass = getWindowSizeClass().widthSizeClass
 
     when {
         widthSizeClass <= WindowWidthSizeClass.Compact -> {
             Box(modifier = modifier) {
-                AnimatedContent(
-                    targetState = showThread,
-                    transitionSpec = {
-                        if (targetState) {
-                            DefaultTransition.navigateForward
-                        } else {
-                            DefaultTransition.navigateBack
-                        }.using(
-                            SizeTransform(clip = false)
-                        )
-                    },
-                    label = "ConversationScreen chatList thread navigation animation"
-                ) { _showThread ->
-                    if (_showThread) {
-                        ConversationThreadScreen(
-                            modifier = Modifier.fillMaxSize(),
-                            viewModel = viewModel,
-                            onNavigateUp = onNavigateUp
-                        )
-                    } else {
-                        ConversationChatListScreen(
-                            modifier = Modifier.fillMaxSize(),
-                            viewModel = viewModel,
-                            courseId = courseId,
-                            conversationId = conversationId,
-                            onNavigateBack = onCloseConversation,
-                            onNavigateToSettings = onNavigateToSettings,
-                            onClickViewPost = onClickViewPost
-                        )
-                    }
-                }
+                priorityColumn(Modifier.fillMaxSize())
             }
         }
 
         else -> {
-            val arrangement = Arrangement.spacedBy(8.dp)
-
             Row(
                 modifier = modifier,
-                horizontalArrangement = arrangement
+                horizontalArrangement = Arrangement.spacedBy(8.dp)
             ) {
-                val isOverviewVisible = !showThread || widthSizeClass >= WindowWidthSizeClass.Expanded
-                AnimatedVisibility(
+                Box(
                     modifier = Modifier
-                        .weight(ConversationOverviewMaxWeight)
-                        .widthIn(max = ConversationOverviewMaxWidth)
-                        .fillMaxHeight(),
-                    visible = isOverviewVisible
+                        .weight(optionalColumnWeight)
+                        .fillMaxHeight()
                 ) {
-                    Row(
-                        modifier = Modifier.fillMaxSize(),
-                        horizontalArrangement = arrangement
-                    ) {
-                        conversationsOverview(
-                            Modifier
-                                .weight(1f)
-                                .fillMaxHeight()
-                        )
-
-                        VerticalDivider()
-                    }
-                }
-
-                val otherWeight = when {
-                    isOverviewVisible && showThread -> 0.35f
-                    isOverviewVisible && !showThread -> 0.7f
-                    else -> 0.5f
+                    optionalColumn(Modifier.fillMaxSize())
                 }
 
-                val otherModifier = Modifier
-                    .weight(otherWeight)
-                    .fillMaxHeight()
+                VerticalDivider()
 
-                ConversationChatListScreen(
+                Box(
                     modifier = Modifier
-                        .weight(1f)
-                        .fillMaxHeight(),
-                    viewModel = viewModel,
-                    courseId = courseId,
-                    conversationId = conversationId,
-                    onNavigateBack = onCloseConversation,
-                    onNavigateToSettings = onNavigateToSettings,
-                    onClickViewPost = onClickViewPost
-                )
-
-                if (showThread) {
-                    VerticalDivider()
-
-                    ConversationThreadScreen(
-                        modifier = otherModifier,
-                        viewModel = viewModel,
-                        onNavigateUp = onNavigateUp
-                    )
+                        .weight(priorityColumnWeight)
+                        .fillMaxHeight()
+                ) {
+                    priorityColumn(Modifier.fillMaxSize())
                 }
             }
         }

feature/metis/conversation/src/main/kotlin/de/tum/informatics/www1/artemis/native_app/feature/metis/conversation/ui/chatlist/PostsDataState.kt

@@ -2,7 +2,6 @@ package de.tum.informatics.www1.artemis.native_app.feature.metis.conversation.ui
 
 import androidx.paging.LoadState
 import androidx.paging.compose.LazyPagingItems
-import androidx.paging.compose.itemKey
 
 /**
  * Abstract layer over the loaded posts state, so we can use both a Pager and a simple list to display posts.
@@ -72,7 +71,13 @@ sealed interface PostsDataState {
 }
 
 fun LazyPagingItems<ChatListItem>.asPostsDataState(): PostsDataState = when {
-    itemCount == 0 -> PostsDataState.Empty
+    itemCount == 0 -> {
+        if (loadState.isIdle) {
+            PostsDataState.Empty
+        } else {
+            PostsDataState.Loading
+        }
+    }
     loadState.refresh is LoadState.Loading -> PostsDataState.Loading
     loadState.refresh is LoadState.Error -> PostsDataState.Error(::retry)
     else -> PostsDataState.Loaded.WithLazyPagingItems(