feat: improve AppSelectorScreen caching/perf (#2961)

Co-authored-by: planshim <100317079+planshim@users.noreply.github.com>

app/src/main/java/app/revanced/manager/ui/screen/AppSelectorScreen.kt

@@ -24,9 +24,9 @@ import androidx.compose.material3.Text
 import androidx.compose.material3.TopAppBarDefaults
 import androidx.compose.material3.rememberTopAppBarState
 import androidx.compose.runtime.Composable
+import androidx.compose.runtime.collectAsState
 import androidx.compose.runtime.getValue
 import androidx.compose.runtime.mutableStateOf
-import androidx.compose.runtime.remember
 import androidx.compose.runtime.saveable.rememberSaveable
 import androidx.compose.runtime.setValue
 import androidx.compose.ui.Alignment
@@ -68,20 +68,11 @@ fun AppSelectorScreen(
             uri?.let(vm::handleStorageResult)
         }
 
-    val suggestedVersions by vm.suggestedAppVersions.collectAsStateWithLifecycle(emptyMap())
+    val suggestedVersions by vm.suggestedAppVersions.collectAsStateWithLifecycle()
 
-    var filterText by rememberSaveable { mutableStateOf("") }
     var search by rememberSaveable { mutableStateOf(false) }
-
-    val appList by vm.appList.collectAsStateWithLifecycle(initialValue = emptyList())
-    val filteredAppList = remember(appList, filterText) {
-        appList.filter { app ->
-            (vm.loadLabel(app.packageInfo)).contains(
-                filterText,
-                true
-            ) or app.packageName.contains(filterText, true)
-        }
-    }
+    val appList by vm.apps.collectAsStateWithLifecycle()
+    val appsListFiltered by vm.filteredApps.collectAsStateWithLifecycle()
 
     vm.nonSuggestedVersionDialogSubject?.let {
         NonSuggestedVersionDialog(
@@ -90,17 +81,20 @@ fun AppSelectorScreen(
         )
     }
 
-    if (search)
+    if (search) {
+        val filterText by vm.filterText.collectAsState()
+
         SearchView(
             query = filterText,
-            onQueryChange = { filterText = it },
+            onQueryChange = vm::setFilterText,
             onActiveChange = { search = it },
             placeholder = { Text(stringResource(R.string.search_apps)) }
         ) {
-            if (appList.isNotEmpty() && filterText.isNotEmpty()) {
+            val appsFiltered = appsListFiltered
+            if (!appsFiltered.isNullOrEmpty() && filterText.isNotEmpty()) {
                 LazyColumnWithScrollbar(modifier = Modifier.fillMaxSize()) {
                     items(
-                        items = filteredAppList,
+                        items = appsFiltered,
                         key = { it.packageName }
                     ) { app ->
                         ListItem(
@@ -109,9 +103,9 @@ fun AppSelectorScreen(
                             },
                             leadingContent = {
                                 AppIcon(
-                                    app.packageInfo,
-                                    null,
-                                    Modifier.size(36.dp)
+                                    packageInfo = app.packageInfo,
+                                    contentDescription = null,
+                                    modifier = Modifier.size(36.dp)
                                 )
                             },
                             headlineContent = { AppLabel(app.packageInfo) },
@@ -152,6 +146,7 @@ fun AppSelectorScreen(
                 }
             }
         }
+    }
 
     val scrollBehavior = TopAppBarDefaults.pinnedScrollBehavior(rememberTopAppBarState())
 
@@ -198,16 +193,33 @@ fun AppSelectorScreen(
                 HorizontalDivider()
             }
 
-            if (appList.isNotEmpty()) {
+            val apps = appList
+            if (apps == null) {
+                item(key = "LOADING") {
+                    Box(
+                        modifier = Modifier.fillParentMaxSize(),
+                        contentAlignment = Alignment.Center
+                    ) {
+                        LoadingIndicator()
+                    }
+                }
+            } else if (apps.isNotEmpty()) {
                 items(
-                    items = appList,
-                    key = { it.packageName }
+                    items = apps,
+                    key = { "APP-" + it.packageName },
+                    contentType = { "APP" },
                 ) { app ->
                     ListItem(
                         modifier = Modifier.clickable {
                             onSelect(app.packageName)
                         },
-                        leadingContent = { AppIcon(app.packageInfo, null, Modifier.size(36.dp)) },
+                        leadingContent = {
+                            AppIcon(
+                                packageInfo = app.packageInfo,
+                                contentDescription = null,
+                                modifier = Modifier.size(36.dp)
+                            )
+                        },
                         headlineContent = {
                             AppLabel(
                                 app.packageInfo,
@@ -231,15 +243,6 @@ fun AppSelectorScreen(
                             }
                         }
                     )
-
-                }
-            } else {
-                item {
-                    Box(
-                        modifier = Modifier.fillParentMaxSize(), contentAlignment = Alignment.Center
-                    ) {
-                        LoadingIndicator()
-                    }
                 }
             }
         }

app/src/main/java/app/revanced/manager/ui/viewmodel/AppSelectorViewModel.kt

@@ -19,8 +19,12 @@ import app.revanced.manager.util.PM
 import app.revanced.manager.util.toast
 import kotlinx.coroutines.Dispatchers
 import kotlinx.coroutines.channels.Channel
-import kotlinx.coroutines.flow.flowOn
+import kotlinx.coroutines.flow.MutableStateFlow
+import kotlinx.coroutines.flow.SharingStarted
+import kotlinx.coroutines.flow.StateFlow
+import kotlinx.coroutines.flow.combine
 import kotlinx.coroutines.flow.receiveAsFlow
+import kotlinx.coroutines.flow.stateIn
 import kotlinx.coroutines.launch
 import kotlinx.coroutines.withContext
 import java.io.File
@@ -40,16 +44,51 @@ class AppSelectorViewModel(
             "input.apk"
         ).also(File::delete)
     }
-    val appList = pm.appList
+
+    val filterTextFlow = MutableStateFlow("")
+    val filterText: StateFlow<String> = filterTextFlow
+
+    val apps = pm.appList.stateIn(
+        scope = viewModelScope,
+        started = SharingStarted.WhileSubscribed(),
+        initialValue = null,
+    )
+
+    val filteredApps = filterText
+        .combine(apps) { filter, apps ->
+            if (apps == null || filter.isBlank()) {
+                apps
+            } else {
+                apps.filter { app ->
+                    app.packageName.contains(filter, true) ||
+                            loadLabel(app.packageInfo).contains(filter)
+                }
+            }
+        }.stateIn(
+            scope = viewModelScope,
+            started = SharingStarted.WhileSubscribed(
+                stopTimeoutMillis = 0,
+                replayExpirationMillis = 10_000,
+            ),
+            initialValue = null,
+        )
 
     private val storageSelectionChannel = Channel<SelectedApp.Local>()
     val storageSelectionFlow = storageSelectionChannel.receiveAsFlow()
 
-    val suggestedAppVersions = patchBundleRepository.suggestedVersions.flowOn(Dispatchers.Default)
+    val suggestedAppVersions = patchBundleRepository.suggestedVersions.stateIn(
+        scope = viewModelScope,
+        started = SharingStarted.WhileSubscribed(),
+        initialValue = emptyMap(),
+    )
 
     var nonSuggestedVersionDialogSubject by mutableStateOf<SelectedApp.Local?>(null)
         private set
 
+    fun setFilterText(filter: String) {
+        filterTextFlow.value = filter
+    }
+
     fun loadLabel(app: PackageInfo?) = with(pm) { app?.label() ?: "Not installed" }
 
     fun dismissNonSuggestedVersionDialog() {