Keep selected Android originals while the catalog finishes loading

tools/chatgui-android/app/src/main/java/com/utun/chat/ui/screens/AvatarViewerScreen.kt

@@ -42,19 +42,19 @@ fun AvatarViewerScreen(group: String?, owner: Long, name: String, onClose: () ->
     LaunchedEffect(account,revision) { if (account==0L) onClose() }
     LaunchedEffect(source?.first,source?.second?.avatarServer,source?.second?.avatarFile,retry) {
         val (channel,member)=source ?: return@LaunchedEffect
-        files=listOf(member.avatarFile); if (selected !in files) selected=member.avatarFile
+        if (selected.isEmpty()) selected=member.avatarFile
+        if (files.isEmpty()) files=listOf(member.avatarFile)
         catalogFailed=false
-        try { files=repository.catalog(channel,member) }
+        try { files=repository.catalog(channel,member); if (selected !in files) selected=member.avatarFile }
         catch (e: CancellationException) { throw e }
         catch (e: Exception) { catalogFailed=true; LogManager.addLog("WARN","Avatar","Catalog failed owner=$owner: ${e.message}") }
     }
     val index=files.indexOf(selected)
-    LaunchedEffect(source?.first,source?.second?.avatarServer,selected,files,retry) {
+    val visible=if (index<0) emptyList() else files.subList((index-2).coerceAtLeast(0),(index+3).coerceAtMost(files.size))
+    LaunchedEffect(source?.first,source?.second?.avatarServer,selected,retry) {
         original=null; failed=false
         val (channel,member)=source ?: return@LaunchedEffect
         if (index<0) return@LaunchedEffect
-        val visible=files.subList((index-2).coerceAtLeast(0),(index+3).coerceAtMost(files.size))
-        previews=previews.filterKeys { it in visible }
         coroutineScope {
             launch {
                 try { previews=previews+(selected to repository.loadAvatar(channel,member.copy(avatarFile=selected),false)) }
@@ -66,13 +66,17 @@ fun AvatarViewerScreen(group: String?, owner: Long, name: String, onClose: () ->
                 catch (e: CancellationException) { throw e }
                 catch (e: Exception) { failed=true; LogManager.addLog("WARN","Avatar","Original failed file=$selected: ${e.message}") }
             }
-            visible.filter { it!=selected && it !in previews }.forEach { file -> launch {
-                try { previews=previews+(file to repository.loadAvatar(channel,member.copy(avatarFile=file),false)) }
-                catch (e: CancellationException) { throw e }
-                catch (e: Exception) { LogManager.addLog("WARN","Avatar","Neighbor failed file=$file: ${e.message}") }
-            } }
         }
     }
+    LaunchedEffect(source?.first,source?.second?.avatarServer,visible,retry) {
+        val (channel,member)=source ?: return@LaunchedEffect
+        previews=previews.filterKeys { it in visible }
+        coroutineScope { visible.filter { it!=selected && it !in previews }.forEach { file -> launch {
+            try { previews=previews+(file to repository.loadAvatar(channel,member.copy(avatarFile=file),false)) }
+            catch (e: CancellationException) { throw e }
+            catch (e: Exception) { LogManager.addLog("WARN","Avatar","Neighbor failed file=$file: ${e.message}") }
+        } } }
+    }
     fun move(delta: Int) { val next=index+delta; if (next in files.indices) selected=files[next] }
     Dialog(onDismissRequest=onClose,properties=DialogProperties(usePlatformDefaultWidth=false)) {
         Column(Modifier.fillMaxSize().background(Color.Black).systemBarsPadding()) {