UI: hide the stubbing actions in Conversation screen

examples/llama.android/app/src/main/java/com/example/llama/MainActivity.kt

@@ -290,11 +290,11 @@ fun AppContent(
             val modelThinkingOrSpeaking =
                 engineState is State.ProcessingUserPrompt || engineState is State.Generating
 
-            val showStubMessage = {
-                handleScaffoldEvent(ScaffoldEvent.ShowSnackbar(
-                    message = "Stub for now, let me know if you want it done :)"
-                ))
-            }
+            val showStubMessage = null  //            {
+//                handleScaffoldEvent(ScaffoldEvent.ShowSnackbar(
+//                    message = "Stub for now, let me know if you want it done :)"
+//                ))
+//            }
 
             ScaffoldConfig(
                 topBarConfig = TopBarConfig.Performance(

examples/llama.android/app/src/main/java/com/example/llama/ui/scaffold/bottombar/BottomBarConfig.kt

@@ -102,8 +102,8 @@ sealed class BottomBarConfig {
         val onSendClick: () -> Unit,
         val showModelCard: Boolean,
         val onToggleModelCard: (Boolean) -> Unit,
-        val onAttachPhotoClick: () -> Unit,
-        val onAttachFileClick: () -> Unit,
-        val onAudioInputClick: () -> Unit,
+        val onAttachPhotoClick: (() -> Unit)?,
+        val onAttachFileClick: (() -> Unit)?,
+        val onAudioInputClick: (() -> Unit)?,
     ) : BottomBarConfig()
 }

examples/llama.android/app/src/main/java/com/example/llama/ui/scaffold/bottombar/ConversationBottomBar.kt

@@ -41,9 +41,9 @@ fun ConversationBottomBar(
     onSendClick: () -> Unit,
     showModelCard: Boolean,
     onToggleModelCard: (Boolean) -> Unit,
-    onAttachPhotoClick: () -> Unit,
-    onAttachFileClick: () -> Unit,
-    onAudioInputClick: () -> Unit,
+    onAttachPhotoClick: (() -> Unit)?,
+    onAttachFileClick: (() -> Unit)?,
+    onAudioInputClick: (() -> Unit)?,
 ) {
     val placeholder = if (isReady) "Message ${APP_NAME}..." else "Please wait for ${APP_NAME} to finish"
 
@@ -86,25 +86,31 @@ fun ConversationBottomBar(
 
         BottomAppBar(
             actions = {
-                IconButton(onClick = onAttachPhotoClick) {
-                    Icon(
-                        imageVector = Icons.Outlined.AddPhotoAlternate,
-                        contentDescription = "Attach a photo",
-                    )
+                onAttachPhotoClick?.let {
+                    IconButton(onClick = it) {
+                        Icon(
+                            imageVector = Icons.Outlined.AddPhotoAlternate,
+                            contentDescription = "Attach a photo",
+                        )
+                    }
                 }
 
-                IconButton(onClick = onAttachFileClick) {
-                    Icon(
-                        imageVector = Icons.Outlined.AttachFile,
-                        contentDescription = "Attach a file",
-                    )
+                onAttachFileClick?.let {
+                    IconButton(onClick = it) {
+                        Icon(
+                            imageVector = Icons.Outlined.AttachFile,
+                            contentDescription = "Attach a file",
+                        )
+                    }
                 }
 
-                IconButton(onClick = onAudioInputClick) {
-                    Icon(
-                        imageVector = Icons.Default.Mic,
-                        contentDescription = "Input with voice",
-                    )
+                onAudioInputClick?.let {
+                    IconButton(onClick = it) {
+                        Icon(
+                            imageVector = Icons.Default.Mic,
+                            contentDescription = "Input with voice",
+                        )
+                    }
                 }
 
                 IconButton(onClick = { onToggleModelCard(!showModelCard) } ) {