UI: polish the bottom bars and info view when no models found; show loading in progress while fetching models

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

@@ -192,6 +192,7 @@ fun AppContent(
         // Model selection screen
         currentRoute == AppDestinations.MODELS_ROUTE -> {
             // Collect states for bottom bar
+            val allModels by modelsViewModel.allModels.collectAsState()
             val filteredModels by modelsViewModel.filteredModels.collectAsState()
             val sortOrder by modelsViewModel.sortOrder.collectAsState()
             val showSortMenu by modelsViewModel.showSortMenu.collectAsState()
@@ -202,6 +203,8 @@ fun AppContent(
             val selectedModelsToDelete by modelsManagementViewModel.selectedModelsToDelete.collectAsState()
             val showImportModelMenu by modelsManagementViewModel.showImportModelMenu.collectAsState()
 
+            val hasModelsInstalled = allModels?.isNotEmpty() == true
+
             // Create file launcher for importing local models
             val fileLauncher = rememberLauncherForActivityResult(
                 contract = ActivityResultContracts.OpenDocument()
@@ -242,10 +245,12 @@ fun AppContent(
                     when (modelScreenUiMode) {
                         ModelScreenUiMode.BROWSING ->
                             BottomBarConfig.Models.Browsing(
+                                isSearchingEnabled = hasModelsInstalled,
                                 onToggleSearching = {
                                     modelsViewModel.toggleMode(ModelScreenUiMode.SEARCHING)
                                 },
                                 sorting = BottomBarConfig.Models.Browsing.SortingConfig(
+                                    isEnabled = hasModelsInstalled,
                                     currentOrder = sortOrder,
                                     isMenuVisible = showSortMenu,
                                     toggleMenu = modelsViewModel::toggleSortMenu,
@@ -255,7 +260,7 @@ fun AppContent(
                                     }
                                 ),
                                 filtering = BottomBarConfig.Models.Browsing.FilteringConfig(
-                                    isActive = activeFilters.any { it.value },
+                                    isEnabled = hasModelsInstalled,
                                     filters = activeFilters,
                                     onToggleFilter = modelsViewModel::toggleFilter,
                                     onClearFilters = modelsViewModel::clearFilters,
@@ -292,12 +297,13 @@ fun AppContent(
                             )
 
                         ModelScreenUiMode.MANAGING ->
-                            BottomBarConfig.Models.Management(
+                            BottomBarConfig.Models.Managing(
                                 isDeletionEnabled = filteredModels?.isNotEmpty() == true,
                                 onToggleDeleting = {
                                     modelsViewModel.toggleMode(ModelScreenUiMode.DELETING)
                                 },
-                                sorting = BottomBarConfig.Models.Management.SortingConfig(
+                                sorting = BottomBarConfig.Models.Managing.SortingConfig(
+                                    isEnabled = hasModelsInstalled,
                                     currentOrder = sortOrder,
                                     isMenuVisible = showSortMenu,
                                     toggleMenu = { modelsViewModel.toggleSortMenu(it) },
@@ -306,15 +312,15 @@ fun AppContent(
                                         modelsViewModel.toggleSortMenu(false)
                                     }
                                 ),
-                                filtering = BottomBarConfig.Models.Management.FilteringConfig(
-                                    isActive = activeFilters.any { it.value },
+                                filtering = BottomBarConfig.Models.Managing.FilteringConfig(
+                                    isEnabled = hasModelsInstalled,
                                     filters = activeFilters,
                                     onToggleFilter = modelsViewModel::toggleFilter,
                                     onClearFilters = modelsViewModel::clearFilters,
                                     isMenuVisible = showFilterMenu,
                                     toggleMenu = modelsViewModel::toggleFilterMenu
                                 ),
-                                importing = BottomBarConfig.Models.Management.ImportConfig(
+                                importing = BottomBarConfig.Models.Managing.ImportConfig(
                                     isMenuVisible = showImportModelMenu,
                                     toggleMenu = { show -> modelsManagementViewModel.toggleImportMenu(show) },
                                     importFromLocal = {
@@ -466,9 +472,6 @@ fun AppContent(
                 // Model Selection Screen
                 composable(AppDestinations.MODELS_ROUTE) {
                     ModelsScreen(
-                        onManageModelsClicked = {
-                            // TODO-han.yin: remove this after implementing onboarding flow
-                        },
                         onConfirmSelection = { modelInfo, ramWarning ->
                             if (modelsViewModel.confirmSelectedModel(modelInfo, ramWarning)) {
                                 navigationActions.navigateToModelLoading()

examples/llama.android/app/src/main/java/com/example/llama/ui/components/InfoView.kt

@@ -15,6 +15,7 @@ import androidx.compose.runtime.Composable
 import androidx.compose.ui.Alignment
 import androidx.compose.ui.Modifier
 import androidx.compose.ui.graphics.vector.ImageVector
+import androidx.compose.ui.text.font.FontWeight
 import androidx.compose.ui.text.style.TextAlign
 import androidx.compose.ui.unit.dp
 
@@ -68,7 +69,8 @@ fun InfoView(
         Text(
             text = title,
             style = MaterialTheme.typography.headlineSmall,
-            textAlign = TextAlign.Center
+            textAlign = TextAlign.Center,
+            fontWeight = FontWeight.SemiBold
         )
 
         message?.let {

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

@@ -107,6 +107,7 @@ fun AppScaffold(
 
             is BottomBarConfig.Models.Browsing -> {
                 ModelsBrowsingBottomBar(
+                    isSearchingEnabled = config.isSearchingEnabled,
                     onToggleSearching = config.onToggleSearching,
                     sortingConfig = config.sorting,
                     filteringConfig = config.filtering,
@@ -123,7 +124,7 @@ fun AppScaffold(
                 )
             }
 
-            is BottomBarConfig.Models.Management -> {
+            is BottomBarConfig.Models.Managing -> {
                 ModelsManagementBottomBar(
                     isDeletionEnabled = config.isDeletionEnabled,
                     onToggleDeleting = config.onToggleDeleting,

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

@@ -16,12 +16,14 @@ sealed class BottomBarConfig {
     sealed class Models : BottomBarConfig() {
 
         data class Browsing(
+            val isSearchingEnabled: Boolean,
             val onToggleSearching: () -> Unit,
             val sorting: SortingConfig,
             val filtering: FilteringConfig,
             val runAction: RunActionConfig,
         ) : BottomBarConfig() {
             data class SortingConfig(
+                val isEnabled: Boolean,
                 val currentOrder: ModelSortOrder,
                 val isMenuVisible: Boolean,
                 val toggleMenu: (Boolean) -> Unit,
@@ -29,7 +31,7 @@ sealed class BottomBarConfig {
             )
 
             data class FilteringConfig(
-                val isActive: Boolean,
+                val isEnabled: Boolean,
                 val filters: Map<ModelFilter, Boolean>,
                 val onToggleFilter: (ModelFilter, Boolean) -> Unit,
                 val onClearFilters: () -> Unit,
@@ -45,7 +47,7 @@ sealed class BottomBarConfig {
             val runAction: RunActionConfig,
         ) : BottomBarConfig()
 
-        data class Management(
+        data class Managing(
             val isDeletionEnabled: Boolean,
             val onToggleDeleting: () -> Unit,
             val sorting: SortingConfig,
@@ -53,6 +55,7 @@ sealed class BottomBarConfig {
             val importing: ImportConfig,
         ) : BottomBarConfig() {
             data class SortingConfig(
+                val isEnabled: Boolean,
                 val currentOrder: ModelSortOrder,
                 val isMenuVisible: Boolean,
                 val toggleMenu: (Boolean) -> Unit,
@@ -60,7 +63,7 @@ sealed class BottomBarConfig {
             )
 
             data class FilteringConfig(
-                val isActive: Boolean,
+                val isEnabled: Boolean,
                 val filters: Map<ModelFilter, Boolean>,
                 val onToggleFilter: (ModelFilter, Boolean) -> Unit,
                 val onClearFilters: () -> Unit,

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

@@ -22,15 +22,18 @@ import androidx.compose.material3.FloatingActionButton
 import androidx.compose.material3.HorizontalDivider
 import androidx.compose.material3.Icon
 import androidx.compose.material3.IconButton
+import androidx.compose.material3.IconButtonDefaults
 import androidx.compose.material3.MaterialTheme
 import androidx.compose.material3.Text
 import androidx.compose.runtime.Composable
 import androidx.compose.ui.Modifier
+import androidx.compose.ui.test.isEnabled
 import androidx.compose.ui.unit.dp
 import com.example.llama.data.model.ModelSortOrder
 
 @Composable
 fun ModelsBrowsingBottomBar(
+    isSearchingEnabled: Boolean,
     onToggleSearching: () -> Unit,
     sortingConfig: BottomBarConfig.Models.Browsing.SortingConfig,
     filteringConfig: BottomBarConfig.Models.Browsing.FilteringConfig,
@@ -39,7 +42,10 @@ fun ModelsBrowsingBottomBar(
     BottomAppBar(
         actions = {
             // Enter search action
-            IconButton(onClick = onToggleSearching) {
+            IconButton(
+                enabled = isSearchingEnabled,
+                onClick = onToggleSearching
+            ) {
                 Icon(
                     imageVector = Icons.Default.Search,
                     contentDescription = "Search models"
@@ -47,7 +53,10 @@ fun ModelsBrowsingBottomBar(
             }
 
             // Sorting action
-            IconButton(onClick = { sortingConfig.toggleMenu(true) }) {
+            IconButton(
+                enabled = sortingConfig.isEnabled,
+                onClick = { sortingConfig.toggleMenu(true) }
+            ) {
                 Icon(
                     imageVector = Icons.AutoMirrored.Filled.Sort,
                     contentDescription = "Sort models"
@@ -99,15 +108,20 @@ fun ModelsBrowsingBottomBar(
             }
 
             // Filter action
-            IconButton(onClick = { filteringConfig.toggleMenu(true) }) {
+            val hasFilters = filteringConfig.filters.any { it.value }
+            IconButton(
+                enabled = filteringConfig.isEnabled,
+                colors = IconButtonDefaults.iconButtonColors().copy(
+                    contentColor = if (hasFilters) MaterialTheme.colorScheme.primary
+                    else MaterialTheme.colorScheme.onSurfaceVariant
+                ),
+                onClick = { filteringConfig.toggleMenu(true) }
+            ) {
                 Icon(
                     imageVector =
-                        if (filteringConfig.isActive) Icons.Default.FilterAlt
+                        if (hasFilters) Icons.Default.FilterAlt
                         else Icons.Outlined.FilterAlt,
                     contentDescription = "Filter models",
-                    tint =
-                        if (filteringConfig.isActive) MaterialTheme.colorScheme.primary
-                        else MaterialTheme.colorScheme.onSurfaceVariant
                 )
             }
 

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

@@ -19,6 +19,7 @@ import androidx.compose.material3.FloatingActionButton
 import androidx.compose.material3.HorizontalDivider
 import androidx.compose.material3.Icon
 import androidx.compose.material3.IconButton
+import androidx.compose.material3.IconButtonDefaults
 import androidx.compose.material3.MaterialTheme
 import androidx.compose.material3.Text
 import androidx.compose.runtime.Composable
@@ -33,9 +34,9 @@ import com.example.llama.data.model.ModelSortOrder
 fun ModelsManagementBottomBar(
     isDeletionEnabled: Boolean,
     onToggleDeleting: () -> Unit,
-    sortingConfig: BottomBarConfig.Models.Management.SortingConfig,
-    filteringConfig: BottomBarConfig.Models.Management.FilteringConfig,
-    importingConfig: BottomBarConfig.Models.Management.ImportConfig,
+    sortingConfig: BottomBarConfig.Models.Managing.SortingConfig,
+    filteringConfig: BottomBarConfig.Models.Managing.FilteringConfig,
+    importingConfig: BottomBarConfig.Models.Managing.ImportConfig,
 ) {
     BottomAppBar(
         actions = {
@@ -47,7 +48,10 @@ fun ModelsManagementBottomBar(
             }
 
             // Sorting action
-            IconButton(onClick = { sortingConfig.toggleMenu(true) }) {
+            IconButton(
+                enabled = sortingConfig.isEnabled,
+                onClick = { sortingConfig.toggleMenu(true) }
+            ) {
                 Icon(
                     imageVector = Icons.AutoMirrored.Filled.Sort,
                     contentDescription = "Sort models"
@@ -99,15 +103,20 @@ fun ModelsManagementBottomBar(
             }
 
             // Filtering action
-            IconButton(onClick = { filteringConfig.toggleMenu(true) }) {
+            val hasFilters = filteringConfig.filters.any { it.value }
+            IconButton(
+                enabled = filteringConfig.isEnabled,
+                onClick = { filteringConfig.toggleMenu(true) },
+                colors = IconButtonDefaults.iconButtonColors().copy(
+                    contentColor = if (hasFilters) MaterialTheme.colorScheme.primary
+                    else MaterialTheme.colorScheme.onSurfaceVariant
+                ),
+            ) {
                 Icon(
                     imageVector =
-                        if (filteringConfig.isActive) Icons.Default.FilterAlt
+                        if (hasFilters) Icons.Default.FilterAlt
                         else Icons.Outlined.FilterAlt,
                     contentDescription = "Filter models",
-                    tint =
-                        if (filteringConfig.isActive) MaterialTheme.colorScheme.primary
-                        else MaterialTheme.colorScheme.onSurfaceVariant
                 )
             }
 

examples/llama.android/app/src/main/java/com/example/llama/ui/screens/ModelsBrowsingScreen.kt

@@ -1,14 +1,16 @@
 package com.example.llama.ui.screens
 
 import androidx.compose.foundation.layout.Arrangement
+import androidx.compose.foundation.layout.Box
 import androidx.compose.foundation.layout.PaddingValues
 import androidx.compose.foundation.layout.fillMaxSize
 import androidx.compose.foundation.lazy.LazyColumn
 import androidx.compose.foundation.lazy.items
 import androidx.compose.material.icons.Icons
-import androidx.compose.material.icons.filled.Add
+import androidx.compose.material.icons.automirrored.filled.ArrowForward
 import androidx.compose.material.icons.filled.FolderOpen
 import androidx.compose.runtime.Composable
+import androidx.compose.ui.Alignment
 import androidx.compose.ui.Modifier
 import androidx.compose.ui.unit.dp
 import com.example.llama.data.model.ModelInfo
@@ -30,7 +32,29 @@ fun ModelsBrowsingScreen(
         ModelsLoadingInProgressView()
     } else if (filteredModels.isEmpty()) {
         // Empty model prompt
-        EmptyModelsView(activeFiltersCount, onManageModelsClicked)
+        val title = when (activeFiltersCount) {
+            0 -> "No models installed yet"
+            1 -> "No models match your filter"
+            else -> "No models match your filters"
+        }
+        val message = when (activeFiltersCount) {
+            0 -> "Tap the button below to install your first Large Language Model!"
+            1 -> "Try removing your filter to see more results"
+            else -> "Try removing some filters to see more results"
+        }
+        Box(modifier = Modifier.fillMaxSize()) {
+            InfoView(
+                modifier = Modifier.fillMaxSize(0.9f).align(Alignment.Center),
+                title = title,
+                icon = Icons.Default.FolderOpen,
+                message = message,
+                action = InfoAction(
+                    label = "Get Started",
+                    icon = Icons.AutoMirrored.Default.ArrowForward,
+                    onAction = onManageModelsClicked
+                )
+            )
+        }
     } else {
         // Model cards
         LazyColumn(
@@ -54,26 +78,3 @@ fun ModelsBrowsingScreen(
         }
     }
 }
-
-@Composable
-private fun EmptyModelsView(
-    activeFiltersCount: Int,
-    onManageModelsClicked: () -> Unit
-) {
-    val message = when (activeFiltersCount) {
-        0 -> "Import some models to get started!"
-        1 -> "No models match the selected filter"
-        else -> "No models match the selected filters"
-    }
-    InfoView(
-        modifier = Modifier.fillMaxSize(),
-        title = "No Models Available",
-        icon = Icons.Default.FolderOpen,
-        message = message,
-        action = InfoAction(
-            label = "Add Models",
-            icon = Icons.Default.Add,
-            onAction = onManageModelsClicked
-        )
-    )
-}

examples/llama.android/app/src/main/java/com/example/llama/ui/screens/ModelsManagementAndDeletingScreen.kt

@@ -56,7 +56,6 @@ import androidx.compose.ui.text.style.TextOverflow
 import androidx.compose.ui.unit.dp
 import androidx.compose.ui.window.DialogProperties
 import androidx.core.net.toUri
-import com.example.llama.data.model.ModelFilter
 import com.example.llama.data.model.ModelInfo
 import com.example.llama.data.source.remote.HuggingFaceModel
 import com.example.llama.ui.components.InfoAction
@@ -110,18 +109,18 @@ fun ModelsManagementAndDeletingScreen(
             ModelsLoadingInProgressView()
         } else if (filteredModels.isEmpty()) {
             // Import model prompt
-            val message = when (activeFiltersCount) {
-                0 -> "Tap the \"+\" button\n to import a model"
+            val title = when (activeFiltersCount) {
+                0 -> "Tap the \"+\" button\n to install a model"
                 1 -> "No models match\n the selected filter"
                 else -> "No models match\n the selected filters"
             }
             InfoView(
-                modifier = Modifier.fillMaxSize(0.8f).align(Alignment.Center),
-                title = message,
+                modifier = Modifier.fillMaxSize(0.9f).align(Alignment.Center),
+                title = title,
                 icon = Icons.Default.FolderOpen,
                 message = "Import a local GGUF model file, or download directly from HuggingFace!",
                 action = InfoAction(
-                    label = "Learn more",
+                    label = "Learn More",
                     icon = Icons.AutoMirrored.Default.Help,
                     onAction = {
                         val url = "https://huggingface.co/docs/hub/en/gguf"

examples/llama.android/app/src/main/java/com/example/llama/ui/screens/ModelsScreen.kt

@@ -33,7 +33,6 @@ import com.example.llama.viewmodel.PreselectedModelToRun.RamWarning
 @OptIn(ExperimentalMaterial3Api::class)
 @Composable
 fun ModelsScreen(
-    onManageModelsClicked: () -> Unit,
     onConfirmSelection: (ModelInfo, RamWarning) -> Unit,
     onScaffoldEvent: (ScaffoldEvent) -> Unit,
     modelsViewModel: ModelsViewModel,