Room: avoid calling displayName/avatarData on each recomposition

appnav/src/main/kotlin/io/element/android/appnav/room/LoadingRoomNodeView.kt

@@ -16,19 +16,13 @@
 
 package io.element.android.appnav.room
 
-import androidx.compose.foundation.background
 import androidx.compose.foundation.layout.Box
 import androidx.compose.foundation.layout.Column
 import androidx.compose.foundation.layout.ExperimentalLayoutApi
-import androidx.compose.foundation.layout.Row
-import androidx.compose.foundation.layout.Spacer
 import androidx.compose.foundation.layout.WindowInsets
 import androidx.compose.foundation.layout.consumeWindowInsets
 import androidx.compose.foundation.layout.fillMaxSize
 import androidx.compose.foundation.layout.padding
-import androidx.compose.foundation.layout.size
-import androidx.compose.foundation.layout.width
-import androidx.compose.foundation.shape.CircleShape
 import androidx.compose.material3.ExperimentalMaterial3Api
 import androidx.compose.runtime.Composable
 import androidx.compose.ui.Alignment
@@ -37,9 +31,8 @@ import androidx.compose.ui.res.stringResource
 import androidx.compose.ui.tooling.preview.Preview
 import androidx.compose.ui.tooling.preview.PreviewParameter
 import androidx.compose.ui.unit.dp
-import androidx.compose.ui.unit.sp
 import io.element.android.features.networkmonitor.api.ui.ConnectivityIndicatorView
-import io.element.android.libraries.designsystem.atomic.atoms.PlaceholderAtom
+import io.element.android.libraries.designsystem.atomic.molecules.IconTitlePlaceholdersRowMolecule
 import io.element.android.libraries.designsystem.components.avatar.AvatarSize
 import io.element.android.libraries.designsystem.components.button.BackButton
 import io.element.android.libraries.designsystem.preview.ElementPreviewDark
@@ -48,7 +41,6 @@ import io.element.android.libraries.designsystem.theme.components.CircularProgre
 import io.element.android.libraries.designsystem.theme.components.Scaffold
 import io.element.android.libraries.designsystem.theme.components.Text
 import io.element.android.libraries.designsystem.theme.components.TopAppBar
-import io.element.android.libraries.designsystem.theme.placeholderBackground
 import io.element.android.libraries.theme.ElementTheme
 import io.element.android.libraries.ui.strings.CommonStrings
 
@@ -103,20 +95,7 @@ private fun LoadingRoomTopBar(
             BackButton(onClick = onBackClicked)
         },
         title = {
-            Row(
-                verticalAlignment = Alignment.CenterVertically
-            ) {
-                Box(
-                    modifier = Modifier
-                        .size(AvatarSize.TimelineRoom.dp)
-                        .align(Alignment.CenterVertically)
-                        .background(color = ElementTheme.colors.placeholderBackground, shape = CircleShape)
-                )
-                Spacer(modifier = Modifier.width(8.dp))
-                PlaceholderAtom(width = 20.dp, height = 7.dp)
-                Spacer(modifier = Modifier.width(7.dp))
-                PlaceholderAtom(width = 45.dp, height = 7.dp)
-            }
+            IconTitlePlaceholdersRowMolecule(iconSize = AvatarSize.TimelineRoom.dp)
         },
         windowInsets = WindowInsets(0.dp),
     )

features/messages/impl/src/main/kotlin/io/element/android/features/messages/impl/MessagesPresenter.kt

@@ -24,7 +24,6 @@ import androidx.compose.runtime.collectAsState
 import androidx.compose.runtime.derivedStateOf
 import androidx.compose.runtime.getValue
 import androidx.compose.runtime.mutableStateOf
-import androidx.compose.runtime.produceState
 import androidx.compose.runtime.remember
 import androidx.compose.runtime.rememberCoroutineScope
 import androidx.compose.runtime.saveable.rememberSaveable
@@ -76,6 +75,7 @@ import io.element.android.libraries.matrix.ui.room.canSendMessageAsState
 import io.element.android.libraries.textcomposer.MessageComposerMode
 import kotlinx.coroutines.CoroutineScope
 import kotlinx.coroutines.launch
+import kotlinx.coroutines.withContext
 import timber.log.Timber
 
 class MessagesPresenter @AssistedInject constructor(
@@ -109,11 +109,13 @@ class MessagesPresenter @AssistedInject constructor(
 
         val syncUpdateFlow = room.syncUpdateFlow.collectAsState()
         val userHasPermissionToSendMessage by room.canSendMessageAsState(type = MessageEventType.ROOM_MESSAGE, updateKey = syncUpdateFlow.value)
-        val roomName by produceState(initialValue = room.displayName, key1 = syncUpdateFlow.value) {
-            value = room.displayName
-        }
-        val roomAvatar by produceState(initialValue = room.avatarData(), key1 = syncUpdateFlow.value) {
-            value = room.avatarData()
+        var roomName: Async<String> by remember { mutableStateOf(Async.Uninitialized) }
+        var roomAvatar: Async<AvatarData> by remember { mutableStateOf(Async.Uninitialized) }
+        LaunchedEffect(syncUpdateFlow.value) {
+            withContext(dispatchers.io) {
+                roomName = Async.Success(room.displayName)
+                roomAvatar = Async.Success(room.avatarData())
+            }
         }
         var hasDismissedInviteDialog by rememberSaveable {
             mutableStateOf(false)

features/messages/impl/src/main/kotlin/io/element/android/features/messages/impl/MessagesState.kt

@@ -30,8 +30,8 @@ import io.element.android.libraries.matrix.api.core.RoomId
 @Immutable
 data class MessagesState(
     val roomId: RoomId,
-    val roomName: String,
-    val roomAvatar: AvatarData,
+    val roomName: Async<String>,
+    val roomAvatar: Async<AvatarData>,
     val userHasPermissionToSendMessage: Boolean,
     val composerState: MessageComposerState,
     val timelineState: TimelineState,

features/messages/impl/src/main/kotlin/io/element/android/features/messages/impl/MessagesStateProvider.kt

@@ -34,6 +34,10 @@ open class MessagesStateProvider : PreviewParameterProvider<MessagesState> {
     override val values: Sequence<MessagesState>
         get() = sequenceOf(
             aMessagesState(),
+            aMessagesState().copy(
+                roomName = Async.Uninitialized,
+                roomAvatar = Async.Uninitialized,
+            ),
             aMessagesState().copy(hasNetworkConnection = false),
             aMessagesState().copy(composerState = aMessageComposerState().copy(showAttachmentSourcePicker = true)),
             aMessagesState().copy(userHasPermissionToSendMessage = false),
@@ -43,8 +47,8 @@ open class MessagesStateProvider : PreviewParameterProvider<MessagesState> {
 
 fun aMessagesState() = MessagesState(
     roomId = RoomId("!id:domain"),
-    roomName = "Room name",
-    roomAvatar = AvatarData("!id:domain", "Room name", size = AvatarSize.TimelineRoom),
+    roomName = Async.Success("Room name"),
+    roomAvatar = Async.Success(AvatarData("!id:domain", "Room name", size = AvatarSize.TimelineRoom)),
     userHasPermissionToSendMessage = true,
     composerState = aMessageComposerState().copy(
         text = "Hello",

features/messages/impl/src/main/kotlin/io/element/android/features/messages/impl/MessagesView.kt

@@ -43,13 +43,11 @@ import androidx.compose.ui.Modifier
 import androidx.compose.ui.platform.LocalView
 import androidx.compose.ui.res.stringResource
 import androidx.compose.ui.text.font.FontStyle
-import androidx.compose.ui.text.font.FontWeight
 import androidx.compose.ui.text.style.TextAlign
 import androidx.compose.ui.text.style.TextOverflow
 import androidx.compose.ui.tooling.preview.Preview
 import androidx.compose.ui.tooling.preview.PreviewParameter
 import androidx.compose.ui.unit.dp
-import androidx.compose.ui.unit.sp
 import io.element.android.features.messages.impl.actionlist.ActionListEvents
 import io.element.android.features.messages.impl.actionlist.ActionListView
 import io.element.android.features.messages.impl.actionlist.model.TimelineItemAction
@@ -64,10 +62,12 @@ import io.element.android.features.messages.impl.timeline.components.retrysendme
 import io.element.android.features.messages.impl.timeline.model.TimelineItem
 import io.element.android.features.networkmonitor.api.ui.ConnectivityIndicatorView
 import io.element.android.libraries.androidutils.ui.hideKeyboard
+import io.element.android.libraries.designsystem.atomic.molecules.IconTitlePlaceholdersRowMolecule
 import io.element.android.libraries.designsystem.components.ProgressDialog
 import io.element.android.libraries.designsystem.components.ProgressDialogType
 import io.element.android.libraries.designsystem.components.avatar.Avatar
 import io.element.android.libraries.designsystem.components.avatar.AvatarData
+import io.element.android.libraries.designsystem.components.avatar.AvatarSize
 import io.element.android.libraries.designsystem.components.button.BackButton
 import io.element.android.libraries.designsystem.components.dialogs.ConfirmationDialog
 import io.element.android.libraries.designsystem.preview.ElementPreviewDark
@@ -137,8 +137,8 @@ fun MessagesView(
             Column {
                 ConnectivityIndicatorView(isOnline = state.hasNetworkConnection)
                 MessagesViewTopBar(
-                    roomTitle = state.roomName,
-                    roomAvatar = state.roomAvatar,
+                    roomName = state.roomName.dataOrNull(),
+                    roomAvatar = state.roomAvatar.dataOrNull(),
                     onBackPressed = onBackPressed,
                     onRoomDetailsClicked = onRoomDetailsClicked,
                 )
@@ -289,29 +289,50 @@ fun MessagesViewContent(
 @OptIn(ExperimentalMaterial3Api::class)
 @Composable
 fun MessagesViewTopBar(
-    roomTitle: String,
-    roomAvatar: AvatarData,
+    roomName: String?,
+    roomAvatar: AvatarData?,
     modifier: Modifier = Modifier,
     onRoomDetailsClicked: () -> Unit = {},
     onBackPressed: () -> Unit = {},
 ) {
+    @Composable
+    fun RoomAvatarAndNameRow(
+        roomName: String,
+        roomAvatar: AvatarData,
+        modifier: Modifier = Modifier
+    ) {
+        Row(
+            modifier = modifier,
+            verticalAlignment = Alignment.CenterVertically
+        ) {
+            Avatar(roomAvatar)
+            Spacer(modifier = Modifier.width(8.dp))
+            Text(
+                text = roomName,
+                style = ElementTheme.typography.fontBodyLgMedium,
+                maxLines = 1,
+                overflow = TextOverflow.Ellipsis
+            )
+        }
+    }
+
     TopAppBar(
         modifier = modifier,
         navigationIcon = {
             BackButton(onClick = onBackPressed)
         },
         title = {
-            Row(
-                modifier = Modifier.clickable { onRoomDetailsClicked() },
-                verticalAlignment = Alignment.CenterVertically
-            ) {
-                Avatar(roomAvatar)
-                Spacer(modifier = Modifier.width(8.dp))
-                Text(
-                    text = roomTitle,
-                    style = ElementTheme.typography.fontBodyLgMedium,
-                    maxLines = 1,
-                    overflow = TextOverflow.Ellipsis
+            val titleModifier = Modifier.clickable { onRoomDetailsClicked() }
+            if (roomName != null && roomAvatar != null) {
+                RoomAvatarAndNameRow(
+                    roomName = roomName,
+                    roomAvatar = roomAvatar,
+                    modifier = titleModifier
+                )
+            } else {
+                IconTitlePlaceholdersRowMolecule(
+                    iconSize = AvatarSize.TimelineRoom.dp,
+                    modifier = titleModifier
                 )
             }
         },

libraries/designsystem/src/main/kotlin/io/element/android/libraries/designsystem/atomic/molecules/IconTitlePlaceholdersRowMolecule.kt

@@ -0,0 +1,43 @@
+package io.element.android.libraries.designsystem.atomic.molecules
+
+import androidx.compose.foundation.background
+import androidx.compose.foundation.layout.Arrangement
+import androidx.compose.foundation.layout.Box
+import androidx.compose.foundation.layout.Row
+import androidx.compose.foundation.layout.Spacer
+import androidx.compose.foundation.layout.size
+import androidx.compose.foundation.layout.width
+import androidx.compose.foundation.shape.CircleShape
+import androidx.compose.runtime.Composable
+import androidx.compose.ui.Alignment
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.unit.Dp
+import androidx.compose.ui.unit.dp
+import io.element.android.libraries.designsystem.atomic.atoms.PlaceholderAtom
+import io.element.android.libraries.designsystem.theme.placeholderBackground
+import io.element.android.libraries.theme.ElementTheme
+
+@Composable
+fun IconTitlePlaceholdersRowMolecule(
+    iconSize: Dp,
+    modifier: Modifier = Modifier,
+    horizontalArrangement: Arrangement.Horizontal = Arrangement.Start,
+    verticalAlignment: Alignment.Vertical = Alignment.CenterVertically,
+) {
+    Row(
+        modifier = modifier,
+        horizontalArrangement = horizontalArrangement,
+        verticalAlignment = verticalAlignment,
+    ) {
+        Box(
+            modifier = Modifier
+                .size(iconSize)
+                .align(Alignment.CenterVertically)
+                .background(color = ElementTheme.colors.placeholderBackground, shape = CircleShape)
+        )
+        Spacer(modifier = Modifier.width(8.dp))
+        PlaceholderAtom(width = 20.dp, height = 7.dp)
+        Spacer(modifier = Modifier.width(7.dp))
+        PlaceholderAtom(width = 45.dp, height = 7.dp)
+    }
+}