Update: Search query, section & order logic in MainNavVM. Remove: PagedList usage in MainNavVM.

src/main/kotlin/com/looker/droidify/database/DAOs.kt

@@ -87,6 +87,16 @@ interface ProductDao : BaseDao<Product> {
         buildProductQuery(installed, updates, searchQuery, section, order, numberOfItems)
     )
 
+    @RawQuery(observedEntities = [Product::class])
+    fun queryLiveList(query: SupportSQLiteQuery): LiveData<List<Product>>
+
+    fun queryLiveList(
+        installed: Boolean, updates: Boolean, searchQuery: String,
+        section: Section, order: Order, numberOfItems: Int = 0
+    ): LiveData<List<Product>> = queryLiveList(
+        buildProductQuery(installed, updates, searchQuery, section, order, numberOfItems)
+    )
+
     @RawQuery(observedEntities = [Product::class])
     fun queryList(
         query: SupportSQLiteQuery

src/main/kotlin/com/looker/droidify/ui/viewmodels/MainNavFragmentViewModelX.kt

@@ -1,8 +1,6 @@
 package com.looker.droidify.ui.viewmodels
 
 import androidx.lifecycle.*
-import androidx.paging.LivePagedListBuilder
-import androidx.paging.PagedList
 import com.looker.droidify.content.Preferences
 import com.looker.droidify.database.DatabaseX
 import com.looker.droidify.database.entity.Product
@@ -11,46 +9,26 @@ import com.looker.droidify.entity.Order
 import com.looker.droidify.entity.Section
 import com.looker.droidify.ui.fragments.Request
 import com.looker.droidify.ui.fragments.Source
-import kotlinx.coroutines.Dispatchers
-import kotlinx.coroutines.flow.MutableStateFlow
-import kotlinx.coroutines.flow.SharingStarted
-import kotlinx.coroutines.flow.StateFlow
-import kotlinx.coroutines.flow.stateIn
 import kotlinx.coroutines.launch
 
-class MainNavFragmentViewModelX(val db: DatabaseX, primarySource: Source, secondarySource: Source) :
+class MainNavFragmentViewModelX(
+    val db: DatabaseX,
+    primarySource: Source,
+    secondarySource: Source
+) :
     ViewModel() {
 
-    private val _order = MutableStateFlow(Order.LAST_UPDATE)
-    private val _sections = MutableStateFlow<Section>(Section.All)
-    private val _searchQuery = MutableStateFlow("")
-
-    val order: StateFlow<Order> = _order.stateIn(
-        initialValue = Order.LAST_UPDATE,
-        scope = viewModelScope,
-        started = SharingStarted.WhileSubscribed(5000)
-    )
-
-    val sections: StateFlow<Section> = _sections.stateIn(
-        initialValue = Section.All,
-        scope = viewModelScope,
-        started = SharingStarted.WhileSubscribed(5000)
-    )
-    val searchQuery: StateFlow<String> = _searchQuery.stateIn(
-        initialValue = "",
-        scope = viewModelScope,
-        started = SharingStarted.WhileSubscribed(5000)
-    )
+    private val order = MutableLiveData(Order.LAST_UPDATE)
+    private val sections = MutableLiveData<Section>(Section.All)
+    private val searchQuery = MutableLiveData("")
 
     fun request(source: Source): Request {
         var mSearchQuery = ""
         var mSections: Section = Section.All
         var mOrder: Order = Order.NAME
-        viewModelScope.launch {
-            launch { searchQuery.collect { if (source.sections) mSearchQuery = it } }
-            launch { sections.collect { if (source.sections) mSections = it } }
-            launch { order.collect { if (source.order) mOrder = it } }
-        }
+        sections.value?.let { if (source.sections) mSections = it }
+        order.value?.let { if (source.order) mOrder = it }
+        searchQuery.value?.let { if (source.sections) mSearchQuery = it }
         return when (source) {
             Source.AVAILABLE -> Request.ProductsAll(
                 mSearchQuery,
@@ -83,73 +61,58 @@ class MainNavFragmentViewModelX(val db: DatabaseX, primarySource: Source, second
         }
     }
 
-    private val pagedListConfig by lazy {
-        PagedList.Config.Builder()
-            .setPageSize(30)
-            .setPrefetchDistance(30)
-            .setEnablePlaceholders(false)
-            .build()
-    }
-    private val primaryRequest = request(primarySource)
-    val primaryProducts: LiveData<PagedList<Product>> by lazy {
-        LivePagedListBuilder(
-            db.productDao.queryList(
-                installed = primaryRequest.installed,
-                updates = primaryRequest.updates,
-                searchQuery = primaryRequest.searchQuery,
-                section = primaryRequest.section,
-                order = primaryRequest.order,
-                numberOfItems = primaryRequest.numberOfItems
-            ), pagedListConfig
-        ).build()
-    }
-    private val secondaryRequest = request(secondarySource)
-    val secondaryProducts: LiveData<PagedList<Product>> by lazy {
-        LivePagedListBuilder(
-            db.productDao.queryList(
-                installed = secondaryRequest.installed,
-                updates = secondaryRequest.updates,
-                searchQuery = secondaryRequest.searchQuery,
-                section = secondaryRequest.section,
-                order = secondaryRequest.order,
-                numberOfItems = secondaryRequest.numberOfItems
-            ), pagedListConfig
-        ).build()
-    }
+    private var primaryRequest = request(primarySource)
+    val primaryProducts = MediatorLiveData<List<Product>>()
+    private var secondaryRequest = request(secondarySource)
+    val secondaryProducts = MediatorLiveData<List<Product>>()
 
     val repositories = MediatorLiveData<List<Repository>>()
 
     init {
+        primaryProducts.addSource(
+            productsListMediator(primaryRequest),
+            primaryProducts::setValue
+        )
+        secondaryProducts.addSource(
+            productsListMediator(secondaryRequest),
+            secondaryProducts::setValue
+        )
         repositories.addSource(db.repositoryDao.allLive, repositories::setValue)
     }
 
-    fun setSection(newSection: Section, perform: () -> Unit) {
+    fun setSection(newSection: Section) {
         viewModelScope.launch {
             if (newSection != sections.value) {
-                _sections.emit(newSection)
-                launch(Dispatchers.Main) { perform() }
+                sections.value = newSection
             }
         }
     }
 
-    fun setOrder(newOrder: Order, perform: () -> Unit) {
+    fun setSection(newOrder: Order) {
         viewModelScope.launch {
             if (newOrder != order.value) {
-                _order.emit(newOrder)
-                launch(Dispatchers.Main) { perform() }
+                order.value = newOrder
             }
         }
     }
 
-    fun setSearchQuery(newSearchQuery: String, perform: () -> Unit) {
+    fun setSection(newSearchQuery: String) {
         viewModelScope.launch {
             if (newSearchQuery != searchQuery.value) {
-                _searchQuery.emit(newSearchQuery)
-                launch(Dispatchers.Main) { perform() }
+                searchQuery.value = newSearchQuery
             }
         }
     }
 
+    private fun productsListMediator(request: Request) = db.productDao.queryLiveList(
+        installed = request.installed,
+        updates = request.updates,
+        searchQuery = request.searchQuery,
+        section = request.section,
+        order = request.order,
+        numberOfItems = request.numberOfItems
+    )
+
     class Factory(
         val db: DatabaseX,
         private val primarySource: Source,