Performance Improvements when rendering a channel creation note

app/src/main/java/com/vitorpamplona/amethyst/ui/note/NoteCompose.kt

@@ -162,7 +162,7 @@ fun NoteCompose(
     val noteForReports = remember(noteReportsState) { noteReportsState?.note } ?: return
 
     val noteEvent = remember(noteState) { note.event }
-    val baseChannel = remember(noteState) { note.channel() }
+    val channelHex = remember(noteState) { note.channelHex() }
     val isSensitive = remember(noteState) { note.event?.isSensitive() ?: false }
 
     var popupExpanded by remember { mutableStateOf(false) }
@@ -212,8 +212,8 @@ fun NoteCompose(
                 nav,
                 onClick = { showHiddenNote = true }
             )
-        } else if ((noteEvent is ChannelCreateEvent || noteEvent is ChannelMetadataEvent) && baseChannel != null) {
+        } else if ((noteEvent is ChannelCreateEvent || noteEvent is ChannelMetadataEvent) && channelHex != null) {
-            ChannelHeader(baseChannel = baseChannel, account = account, nav = nav)
+            ChannelHeader(channelHex = channelHex, account = account, nav = nav)
         } else if (noteEvent is BadgeDefinitionEvent) {
             BadgeDisplay(baseNote = note)
         } else if (noteEvent is FileHeaderEvent) {
@@ -581,14 +581,15 @@ private fun RenderPrivateMessage(
     val noteEvent = note.event as? PrivateDmEvent ?: return
 
     val withMe = remember { noteEvent.with(accountViewModel.userProfile().pubkeyHex) }
-    val tags = remember(note.event?.id()) { note.event?.tags() }
-    val hashtags = remember(note.event?.id()) { note.event?.hashtags() ?: emptyList() }
-    val modifier = remember(note.event?.id()) { Modifier.fillMaxWidth() }
-    val isAuthorTheLoggedUser = remember(note.event?.id()) { accountViewModel.isLoggedUser(note.author) }
 
     if (withMe) {
         val eventContent = remember { accountViewModel.decrypt(note) }
 
+        val hashtags = remember(note.event?.id()) { note.event?.hashtags() ?: emptyList() }
+        val modifier = remember(note.event?.id()) { Modifier.fillMaxWidth() }
+        val isAuthorTheLoggedUser = remember(note.event?.id()) { accountViewModel.isLoggedUser(note.author) }
+        val tags = remember(note.event?.id()) { note.event?.tags() }
+
         if (eventContent != null) {
             if (makeItShort && isAuthorTheLoggedUser) {
                 Text(
@@ -628,7 +629,7 @@ private fun RenderPrivateMessage(
             ),
             canPreview = !makeItShort,
             Modifier.fillMaxWidth(),
-            noteEvent.tags(),
+            emptyList(),
             backgroundColor,
             accountViewModel,
             nav

app/src/main/java/com/vitorpamplona/amethyst/ui/screen/loggedIn/ChannelScreen.kt

@@ -40,6 +40,7 @@ import androidx.compose.runtime.getValue
 import androidx.compose.runtime.livedata.observeAsState
 import androidx.compose.runtime.mutableStateOf
 import androidx.compose.runtime.remember
+import androidx.compose.runtime.rememberCoroutineScope
 import androidx.compose.runtime.setValue
 import androidx.compose.ui.Alignment
 import androidx.compose.ui.Modifier
@@ -63,6 +64,7 @@ import androidx.lifecycle.viewmodel.compose.viewModel
 import com.vitorpamplona.amethyst.R
 import com.vitorpamplona.amethyst.model.Account
 import com.vitorpamplona.amethyst.model.Channel
+import com.vitorpamplona.amethyst.model.LocalCache
 import com.vitorpamplona.amethyst.model.Note
 import com.vitorpamplona.amethyst.service.NostrChannelDataSource
 import com.vitorpamplona.amethyst.ui.actions.NewChannelView
@@ -77,6 +79,8 @@ import com.vitorpamplona.amethyst.ui.navigation.Route
 import com.vitorpamplona.amethyst.ui.note.ChatroomMessageCompose
 import com.vitorpamplona.amethyst.ui.screen.ChatroomFeedView
 import com.vitorpamplona.amethyst.ui.screen.NostrChannelFeedViewModel
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.launch
 
 @Composable
 fun ChannelScreen(
@@ -158,7 +162,12 @@ fun ChannelScreen(
 
             Spacer(modifier = Modifier.height(10.dp))
 
-            Row(Modifier.padding(horizontal = 10.dp).animateContentSize(), verticalAlignment = Alignment.CenterVertically) {
+            Row(
+                Modifier
+                    .padding(horizontal = 10.dp)
+                    .animateContentSize(),
+                verticalAlignment = Alignment.CenterVertically
+            ) {
                 val replyingNote = replyTo.value
                 if (replyingNote != null) {
                     Column(Modifier.weight(1f)) {
@@ -182,7 +191,9 @@ fun ChannelScreen(
                             Icon(
                                 imageVector = Icons.Default.Cancel,
                                 null,
-                                modifier = Modifier.padding(end = 5.dp).size(30.dp),
+                                modifier = Modifier
+                                    .padding(end = 5.dp)
+                                    .size(30.dp),
                                 tint = MaterialTheme.colors.onSurface.copy(alpha = 0.32f)
                             )
                         }
@@ -192,7 +203,9 @@ fun ChannelScreen(
 
             // LAST ROW
             Row(
-                modifier = Modifier.padding(start = 10.dp, end = 10.dp, bottom = 10.dp, top = 5.dp).fillMaxWidth(),
+                modifier = Modifier
+                    .padding(start = 10.dp, end = 10.dp, bottom = 10.dp, top = 5.dp)
+                    .fillMaxWidth(),
                 horizontalArrangement = Arrangement.SpaceBetween,
                 verticalAlignment = Alignment.CenterVertically
             ) {
@@ -246,10 +259,26 @@ fun ChannelScreen(
     }
 }
 
+@Composable
+fun ChannelHeader(channelHex: String, account: Account, nav: (String) -> Unit) {
+    var baseChannel by remember { mutableStateOf<Channel?>(null) }
+    val scope = rememberCoroutineScope()
+
+    LaunchedEffect(key1 = channelHex) {
+        scope.launch(Dispatchers.IO) {
+            baseChannel = LocalCache.checkGetOrCreateChannel(channelHex)
+        }
+    }
+
+    baseChannel?.let {
+        ChannelHeader(it, account, nav)
+    }
+}
+
 @Composable
 fun ChannelHeader(baseChannel: Channel, account: Account, nav: (String) -> Unit) {
     val channelState by baseChannel.live.observeAsState()
-    val channel = channelState?.channel ?: return
+    val channel = remember(channelState) { channelState?.channel } ?: return
 
     val context = LocalContext.current.applicationContext