RoomList: simple implementation of setRange

features/roomlist/src/main/java/io/element/android/x/features/roomlist/RoomListScreen.kt

@@ -13,7 +13,9 @@ import androidx.compose.material3.Scaffold
 import androidx.compose.material3.TopAppBarDefaults
 import androidx.compose.material3.rememberTopAppBarState
 import androidx.compose.runtime.Composable
+import androidx.compose.runtime.derivedStateOf
 import androidx.compose.runtime.getValue
+import androidx.compose.runtime.remember
 import androidx.compose.ui.Modifier
 import androidx.compose.ui.input.nestedscroll.nestedScroll
 import androidx.compose.ui.tooling.preview.Preview
@@ -25,7 +27,7 @@ import io.element.android.x.core.compose.LogCompositions
 import io.element.android.x.designsystem.ElementXTheme
 import io.element.android.x.designsystem.components.ProgressDialog
 import io.element.android.x.designsystem.components.avatar.AvatarData
-import io.element.android.x.features.roomlist.components.RoomItem
+import io.element.android.x.features.roomlist.components.RoomSummaryRow
 import io.element.android.x.features.roomlist.components.RoomListTopBar
 import io.element.android.x.features.roomlist.model.MatrixUser
 import io.element.android.x.features.roomlist.model.RoomListRoomSummary
@@ -56,6 +58,7 @@ fun RoomListScreen(
         isLoginOut = logoutAction is Loading,
         filter = filter,
         onFilterChanged = viewModel::filterRoom,
+        onScrollOver = viewModel::updateVisibleRange
     )
 }
 
@@ -67,12 +70,31 @@ fun RoomListContent(
     filter: String,
     onFilterChanged: (String) -> Unit,
     onLogoutClicked: () -> Unit,
+    onScrollOver: (IntRange) -> Unit,
     isLoginOut: Boolean,
 ) {
+
+    fun onRoomClicked(room: RoomListRoomSummary) {
+        onRoomClicked(room.roomId)
+    }
+
     val appBarState = rememberTopAppBarState()
     val lazyListState = rememberLazyListState()
+
+    val visibleRange by remember {
+        derivedStateOf {
+            val layoutInfo = lazyListState.layoutInfo
+            val firstItemIndex = layoutInfo.visibleItemsInfo.firstOrNull()?.index ?: 0
+            val size = layoutInfo.visibleItemsInfo.size
+            firstItemIndex until firstItemIndex + size
+        }
+    }
+    if (!lazyListState.isScrollInProgress) {
+        onScrollOver(visibleRange)
+    }
     val scrollBehavior = TopAppBarDefaults.exitUntilCollapsedScrollBehavior(appBarState)
     LogCompositions(tag = "RoomListScreen", msg = "Content")
+
     Scaffold(
         modifier = Modifier.nestedScroll(scrollBehavior.nestedScrollConnection),
         topBar = {
@@ -91,9 +113,7 @@ fun RoomListContent(
                     state = lazyListState,
                 ) {
                     items(roomSummaries) { room ->
-                        RoomItem(room = room) {
-                            onRoomClicked(it)
-                        }
+                        RoomSummaryRow(room = room, onClick = ::onRoomClicked)
                     }
                 }
             }
@@ -120,6 +140,7 @@ private fun PreviewableRoomListContent() {
             filter = "filter",
             onFilterChanged = {},
             isLoginOut = false,
+            onScrollOver = {}
         )
     }
 }
@@ -136,6 +157,7 @@ private fun PreviewableDarkRoomListContent() {
             filter = "filter",
             onFilterChanged = {},
             isLoginOut = true,
+            onScrollOver = {}
         )
     }
 }

features/roomlist/src/main/java/io/element/android/x/features/roomlist/RoomListViewModel.kt

@@ -66,6 +66,13 @@ class RoomListViewModel(
         }
     }
 
+    fun updateVisibleRange(range: IntRange) {
+        viewModelScope.launch {
+            if (range.isEmpty()) return@launch
+            client.roomSummaryDataSource().setSlidingSyncRange(range)
+        }
+    }
+
     private fun handleInit() {
         suspend {
             val userAvatarUrl = client.loadUserAvatarURLString().getOrNull()

features/roomlist/src/main/java/io/element/android/x/features/roomlist/components/RoomSummaryRow.kt

@@ -0,0 +1,137 @@
+package io.element.android.x.features.roomlist.components
+
+import Avatar
+import androidx.compose.foundation.background
+import androidx.compose.foundation.clickable
+import androidx.compose.foundation.interaction.MutableInteractionSource
+import androidx.compose.foundation.layout.*
+import androidx.compose.foundation.shape.CircleShape
+import androidx.compose.foundation.shape.GenericShape
+import androidx.compose.material.ripple.rememberRipple
+import androidx.compose.material3.MaterialTheme
+import androidx.compose.material3.Text
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.remember
+import androidx.compose.ui.Alignment
+import androidx.compose.ui.Alignment.Companion.CenterVertically
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.draw.clip
+import androidx.compose.ui.geometry.Rect
+import androidx.compose.ui.graphics.Color
+import androidx.compose.ui.text.font.FontWeight
+import androidx.compose.ui.text.style.TextOverflow
+import androidx.compose.ui.unit.dp
+import androidx.compose.ui.unit.sp
+import com.google.accompanist.placeholder.material.placeholder
+import io.element.android.x.features.roomlist.model.RoomListRoomSummary
+
+private val minHeight = 72.dp
+
+@Composable
+internal fun RoomSummaryRow(
+    modifier: Modifier = Modifier,
+    room: RoomListRoomSummary,
+    onClick: (RoomListRoomSummary) -> Unit
+) {
+
+    val clickModifier = if (room.isPlaceholder) {
+        Modifier
+    } else {
+        Modifier.clickable(
+            onClick = { onClick(room) },
+            indication = rememberRipple(),
+            interactionSource = remember { MutableInteractionSource() }
+        )
+    }
+    Box(
+        modifier = modifier
+            .fillMaxWidth()
+            .heightIn(min = minHeight)
+            .then(clickModifier)
+    ) {
+        DefaultRoomSummaryRow(modifier = modifier, room = room)
+    }
+
+}
+
+@Composable
+internal fun DefaultRoomSummaryRow(
+    modifier: Modifier = Modifier,
+    room: RoomListRoomSummary,
+) {
+    val placeholderShape = PlaceholderShape()
+
+    Row(
+        modifier = Modifier
+            .fillMaxWidth()
+            .padding(horizontal = 16.dp)
+            .height(IntrinsicSize.Min),
+        verticalAlignment = CenterVertically
+    ) {
+        Avatar(
+            room.avatarData,
+            modifier = Modifier.placeholder(room.isPlaceholder, shape = CircleShape)
+        )
+        Column(
+            modifier = Modifier
+                .padding(start = 12.dp, end = 4.dp, top = 12.dp, bottom = 12.dp)
+                .alignByBaseline()
+                .weight(1f)
+        ) {
+            // Name
+            Text(
+                modifier = Modifier
+                    .placeholder(room.isPlaceholder, shape = placeholderShape),
+                fontSize = 16.sp,
+                fontWeight = FontWeight.SemiBold,
+                text = room.name,
+                maxLines = 1,
+                overflow = TextOverflow.Ellipsis
+            )
+            // Last Message
+            Text(
+                modifier = Modifier.placeholder(room.isPlaceholder, shape = placeholderShape),
+                text = room.lastMessage?.toString().orEmpty(),
+                color = MaterialTheme.colorScheme.secondary,
+                fontSize = 14.sp,
+                maxLines = 1,
+                overflow = TextOverflow.Ellipsis
+            )
+        }
+        // Timestamp and Unread
+        Column(
+            modifier = Modifier
+                .alignByBaseline(),
+        ) {
+            Text(
+                modifier = Modifier.placeholder(room.isPlaceholder, shape = placeholderShape),
+                fontSize = 12.sp,
+                text = room.timestamp ?: "",
+                color = MaterialTheme.colorScheme.secondary,
+            )
+            Spacer(modifier.size(4.dp))
+            val unreadIndicatorColor =
+                if (room.hasUnread) MaterialTheme.colorScheme.primary else Color.Transparent
+            Box(
+                modifier = Modifier
+                    .size(12.dp)
+                    .clip(CircleShape)
+                    .background(unreadIndicatorColor)
+                    .align(Alignment.End),
+            )
+        }
+    }
+}
+
+@Composable
+fun PlaceholderShape(): GenericShape {
+    return GenericShape { size, _ ->
+        val rect = Rect(
+            0f,
+            size.height / 4,
+            size.width,
+            size.height - size.height / 4
+        )
+        addRect(rect)
+    }
+}

libraries/matrix/src/main/java/io/element/android/x/matrix/MatrixClient.kt

@@ -44,19 +44,19 @@ class MatrixClient internal constructor(
         .requiredState(
             requiredState = listOf(
                 RequiredState(key = "m.room.avatar", value = ""),
-                RequiredState(key = "m.room.name", value = ""),
                 RequiredState(key = "m.room.encryption", value = ""),
             )
         )
         .name(name = "HomeScreenView")
-        .syncMode(mode = SlidingSyncMode.FULL_SYNC)
+        .syncMode(mode = SlidingSyncMode.SELECTIVE)
+        .addRange(0u, 10u)
         .build()
 
     private val slidingSync = client
         .slidingSync()
         .homeserver("https://slidingsync.lab.element.dev")
         .withCommonExtensions()
-        .coldCache("ElementX")
+        //.coldCache("ElementX")
         .addView(slidingSyncView)
         .build()
 
@@ -66,7 +66,8 @@ class MatrixClient internal constructor(
             slidingSyncObserverProxy.updateSummaryFlow,
             slidingSync,
             slidingSyncView,
-            dispatchers
+            dispatchers,
+            ::onRestartSync
         )
     private var slidingSyncObserverToken: StoppableSpawn? = null
 
@@ -77,6 +78,10 @@ class MatrixClient internal constructor(
         client.setDelegate(clientDelegate)
     }
 
+    private fun onRestartSync(){
+        slidingSyncObserverToken = slidingSync.sync()
+    }
+
     fun getRoom(roomId: String): MatrixRoom? {
         val slidingSyncRoom = slidingSync.getRoom(roomId) ?: return null
         val room = slidingSyncRoom.fullRoom() ?: return null

libraries/matrix/src/main/java/io/element/android/x/matrix/room/RoomSummaryDataSource.kt

@@ -12,6 +12,7 @@ import java.util.*
 
 interface RoomSummaryDataSource {
     fun roomSummaries(): Flow<List<RoomSummary>>
+    fun setSlidingSyncRange(range: IntRange)
 }
 
 internal class RustRoomSummaryDataSource(
@@ -19,7 +20,8 @@ internal class RustRoomSummaryDataSource(
     private val slidingSync: SlidingSync,
     private val slidingSyncView: SlidingSyncView,
     private val coroutineDispatchers: CoroutineDispatchers,
-    private val roomSummaryDetailsFactory: RoomSummaryDetailsFactory = RoomSummaryDetailsFactory()
+    private val onRestartSync: () -> Unit,
+    private val roomSummaryDetailsFactory: RoomSummaryDetailsFactory = RoomSummaryDetailsFactory(),
 ) : RoomSummaryDataSource, Closeable {
 
     private val coroutineScope = CoroutineScope(SupervisorJob() + coroutineDispatchers.io)
@@ -69,6 +71,12 @@ internal class RustRoomSummaryDataSource(
         return roomSummaries.sample(50)
     }
 
+    override fun setSlidingSyncRange(range: IntRange) {
+        Timber.v("setVisibleRange=$range")
+        slidingSyncView.setRange(range.first.toUInt(), range.last.toUInt())
+        onRestartSync()
+    }
+
     private suspend fun didReceiveSyncUpdate(summary: UpdateSummary) {
         Timber.v("UpdateRooms with identifiers: ${summary.rooms}")
         if (state.value != SlidingSyncState.LIVE) {
@@ -140,11 +148,12 @@ internal class RustRoomSummaryDataSource(
         )
     }
 
-    private suspend fun updateRoomSummaries(block: MutableList<RoomSummary>.() -> Unit) = withContext(coroutineDispatchers.diffUpdateDispatcher){
-        val mutableRoomSummaries = roomSummaries.value.toMutableList()
-        block(mutableRoomSummaries)
-        roomSummaries.value = mutableRoomSummaries
-    }
+    private suspend fun updateRoomSummaries(block: MutableList<RoomSummary>.() -> Unit) =
+        withContext(coroutineDispatchers.diffUpdateDispatcher) {
+            val mutableRoomSummaries = roomSummaries.value.toMutableList()
+            block(mutableRoomSummaries)
+            roomSummaries.value = mutableRoomSummaries
+        }
 
     fun SlidingSyncViewRoomsListDiff.isInvalidation(): Boolean {
         return when (this) {