di and pagination

app/build.gradle.kts

@@ -83,4 +83,8 @@ dependencies {
     kapt("androidx.room:room-compiler:$room_version")
     implementation("androidx.room:room-ktx:$room_version")
     implementation("androidx.room:room-paging:$room_version")
+
+    //Paging
+    implementation ("androidx.paging:paging-compose:3.2.1")
+    implementation ("androidx.paging:paging-runtime:3.2.1")
 }

app/src/main/java/com/example/androidlabs/App.kt

@@ -7,13 +7,13 @@ import kotlinx.coroutines.Dispatchers
 import kotlinx.coroutines.launch
 
 class App : Application() {
-    val database by lazy { AppDatabase.getInstance(this)}
-
+    lateinit var container: AppContainer
     override fun onCreate() {
         super.onCreate()
         //this.deleteDatabase("my-db")
-        CoroutineScope(Dispatchers.IO).launch {
-            AppDatabase.populateDatabase()
-        }
+        //CoroutineScope(Dispatchers.IO).launch {
+          //  AppDatabase.populateDatabase()
+        //}
+        container = AppDataContainer(this)
     }
 }

app/src/main/java/com/example/androidlabs/AppContainer.kt

@@ -0,0 +1,11 @@
+package com.example.androidlabs
+
+import com.example.androidlabs.DB.repository.HotelRepository
+import com.example.androidlabs.DB.repository.OrderRepository
+import com.example.androidlabs.DB.repository.UserRepository
+
+interface AppContainer {
+    val hotelRepo: HotelRepository
+    val userRepo: UserRepository
+    val orderRepo: OrderRepository
+}

app/src/main/java/com/example/androidlabs/AppDataContainer.kt

@@ -0,0 +1,22 @@
+package com.example.androidlabs
+
+import android.content.Context
+import com.example.androidlabs.DB.AppDatabase
+import com.example.androidlabs.DB.repository.HotelRepImpl
+import com.example.androidlabs.DB.repository.HotelRepository
+import com.example.androidlabs.DB.repository.OrderRepImpl
+import com.example.androidlabs.DB.repository.OrderRepository
+import com.example.androidlabs.DB.repository.UserRepImpl
+import com.example.androidlabs.DB.repository.UserRepository
+
+class AppDataContainer(private val context: Context) : AppContainer {
+    override val hotelRepo: HotelRepository by lazy {
+        HotelRepImpl(AppDatabase.getInstance(context).hotelDao())
+    }
+    override val userRepo: UserRepository by lazy {
+        UserRepImpl(AppDatabase.getInstance(context).userDao())
+    }
+    override val orderRepo: OrderRepository by lazy {
+        OrderRepImpl(AppDatabase.getInstance(context).orderDao())
+    }
+}

app/src/main/java/com/example/androidlabs/DB/AppDatabase.kt

@@ -33,9 +33,9 @@ abstract class AppDatabase : RoomDatabase() {
             INSTANCE?.let { database ->
                 // User
                 val userDao = database.userDao()
-                val user1 = User(null, "Artem", "Emelyanov", "artem@mail.ru", "123", RoleEnum.Admin)
+                val user1 = User(null, "Artem", "Emelyanov", "artem@mail.ru", "123", RoleEnum.User)
                 val user2 = User(null, "Danil", "Markov", "danil@mail.ru", "123", RoleEnum.User)
-                val user3 = User(null, "Viktoria", "Presnyakova", "vika@mail.ru", "123", RoleEnum.User)
+                val user3 = User(null, "Viktoria", "Presnyakova", "vika@mail.ru", "123", RoleEnum.Admin)
                 userDao.createUser(user1)
                 userDao.createUser(user2)
                 userDao.createUser(user3)

app/src/main/java/com/example/androidlabs/DB/dao/HotelDao.kt

@@ -1,4 +1,5 @@
 package com.example.androidlabs.DB.dao
+import androidx.paging.PagingSource
 import androidx.room.Dao
 import androidx.room.Delete
 import androidx.room.Insert
@@ -19,7 +20,7 @@ interface HotelDao {
     suspend fun delete(hotel: Hotel)
 
     @Query("SELECT*FROM Hotel")
-    fun getAllHotelss(): Flow<List<Hotel>>
+    fun getAllHotelsPaged(): PagingSource<Int, Hotel>
 
     @Query("SELECT * FROM Hotel WHERE hotelId = :id")
     suspend fun getHotelById(id: Int): Hotel

app/src/main/java/com/example/androidlabs/DB/dao/OrderDao.kt

@@ -5,6 +5,7 @@ import androidx.room.Delete
 import androidx.room.Insert
 import androidx.room.Query
 import com.example.androidlabs.DB.models.Order
+import com.example.androidlabs.DB.models.UserWithOrder
 import kotlinx.coroutines.flow.Flow
 
 @Dao
@@ -21,4 +22,7 @@ interface OrderDao {
 
     @Delete
     suspend fun delete(order: Order)
+
+    @Query("SELECT * FROM users WHERE userId =:id")
+    fun getUserOrders(id: Int) : Flow<UserWithOrder>
 }

app/src/main/java/com/example/androidlabs/DB/dao/UserDao.kt

@@ -26,6 +26,4 @@ interface UserDao {
     @Query("SELECT * FROM users WHERE email = :email")
     suspend fun getUserByEmail(email: String): User
 
-    @Query("SELECT * FROM users WHERE userId =:id")
-    fun getUserOrders(id: Int) : Flow<UserWithOrder>
 }

app/src/main/java/com/example/androidlabs/DB/repository/HotelRepImpl.kt

@@ -0,0 +1,29 @@
+package com.example.androidlabs.DB.repository
+
+import androidx.paging.Pager
+import androidx.paging.PagingConfig
+import androidx.paging.PagingData
+import com.example.androidlabs.DB.dao.HotelDao
+import com.example.androidlabs.DB.models.Hotel
+import androidx.paging.PagingSource
+import kotlinx.coroutines.flow.Flow
+
+
+class HotelRepImpl (private val hotelDao: HotelDao) : HotelRepository {
+
+    override suspend fun insertHotel(hotel: Hotel) = hotelDao.insert(hotel)
+
+    override suspend fun updateHotel(hotel: Hotel) = hotelDao.update(hotel)
+
+    override suspend fun deleteHotel(hotel: Hotel) = hotelDao.delete(hotel)
+
+    override suspend fun getHotelById(id: Int): Hotel = hotelDao.getHotelById(id)
+    override fun getAllHotelsPaged(): PagingSource<Int, Hotel> = hotelDao.getAllHotelsPaged()
+    override fun call(): Flow<PagingData<Hotel>> {
+        return Pager(
+            PagingConfig(pageSize = 5)
+        ) {
+            hotelDao.getAllHotelsPaged()
+        }.flow
+    }
+}

app/src/main/java/com/example/androidlabs/DB/repository/HotelRepository.kt

@@ -0,0 +1,14 @@
+package com.example.androidlabs.DB.repository
+
+import androidx.paging.PagingSource
+import com.example.androidlabs.DB.models.Hotel
+import kotlinx.coroutines.flow.Flow
+import androidx.paging.PagingData
+interface HotelRepository {
+    suspend fun insertHotel(hotel: Hotel)
+    suspend fun updateHotel(hotel: Hotel)
+    suspend fun deleteHotel(hotel: Hotel)
+    suspend fun getHotelById(id: Int): Hotel
+    fun getAllHotelsPaged(): PagingSource<Int, Hotel>
+    fun call(): Flow<PagingData<Hotel>>
+}

app/src/main/java/com/example/androidlabs/DB/repository/OrderRepImpl.kt

@@ -0,0 +1,17 @@
+package com.example.androidlabs.DB.repository
+
+import com.example.androidlabs.DB.dao.OrderDao
+import com.example.androidlabs.DB.models.Order
+import com.example.androidlabs.DB.models.UserWithOrder
+import kotlinx.coroutines.flow.Flow
+
+class OrderRepImpl (private val orderDao: OrderDao) : OrderRepository {
+
+    override suspend fun createOrder(order: Order): Long = orderDao.createOrder(order)
+
+    override suspend fun delete(order: Order) = orderDao.delete(order)
+
+    override fun getAllOrder(): Flow<List<Order>> = orderDao.getAllOrder()
+
+    override fun getUserOrders(id: Int): Flow<UserWithOrder> = orderDao.getUserOrders(id)
+}

app/src/main/java/com/example/androidlabs/DB/repository/OrderRepository.kt

@@ -0,0 +1,12 @@
+package com.example.androidlabs.DB.repository
+
+import com.example.androidlabs.DB.models.Order
+import com.example.androidlabs.DB.models.UserWithOrder
+import kotlinx.coroutines.flow.Flow
+
+interface OrderRepository {
+    suspend fun createOrder(order: Order): Long
+    suspend fun delete(order: Order)
+    fun getAllOrder(): Flow<List<Order>>
+    fun getUserOrders(id: Int) : Flow<UserWithOrder>
+}

app/src/main/java/com/example/androidlabs/DB/repository/UserRepImpl.kt

@@ -0,0 +1,17 @@
+package com.example.androidlabs.DB.repository
+
+import com.example.androidlabs.DB.dao.UserDao
+import com.example.androidlabs.DB.models.User
+
+class UserRepImpl(private val userDao: UserDao) : UserRepository {
+
+    override suspend fun createUser(user: User) = userDao.createUser(user)
+
+    override suspend fun updateUser(user: User) = userDao.updateUser(user)
+
+    override suspend fun deleteUser(user: User) = userDao.deleteUser(user)
+
+    override suspend fun getUserById(id: Int): User = userDao.getUserById(id)
+
+    override suspend fun getUserByEmail(email: String): User = userDao.getUserByEmail(email)
+}

app/src/main/java/com/example/androidlabs/DB/repository/UserRepository.kt

@@ -0,0 +1,11 @@
+package com.example.androidlabs.DB.repository
+
+import com.example.androidlabs.DB.models.User
+
+interface UserRepository {
+    suspend fun createUser(user: User)
+    suspend fun updateUser(user: User)
+    suspend fun deleteUser(user: User)
+    suspend fun getUserById(id: Int): User
+    suspend fun getUserByEmail(email: String): User
+}

app/src/main/java/com/example/androidlabs/DB/viewModels/AppViewModelProvider.kt

@@ -0,0 +1,24 @@
+package com.example.androidlabs.DB.viewModels
+
+import androidx.lifecycle.ViewModelProvider
+import androidx.lifecycle.viewmodel.CreationExtras
+import androidx.lifecycle.viewmodel.initializer
+import androidx.lifecycle.viewmodel.viewModelFactory
+import com.example.androidlabs.App
+
+object AppViewModelProvider {
+    val Factory = viewModelFactory {
+        initializer {
+            HotelViewModel(app().container.hotelRepo)
+        }
+        initializer {
+            UserViewModel(app().container.userRepo)
+        }
+        initializer {
+            OrderViewModel(app().container.orderRepo)
+        }
+    }
+}
+
+fun CreationExtras.app(): App =
+    (this[ViewModelProvider.AndroidViewModelFactory.APPLICATION_KEY] as App)

app/src/main/java/com/example/androidlabs/DB/viewModels/HotelViewModel.kt

@@ -6,21 +6,23 @@ import androidx.lifecycle.ViewModelProvider
 import androidx.lifecycle.ViewModelProvider.AndroidViewModelFactory.Companion.APPLICATION_KEY
 import androidx.lifecycle.viewModelScope
 import androidx.lifecycle.viewmodel.CreationExtras
+import androidx.paging.cachedIn
 import com.example.androidlabs.App
 import com.example.androidlabs.DB.AppDatabase
 import com.example.androidlabs.DB.models.Hotel
+import com.example.androidlabs.DB.repository.HotelRepository
 import com.example.androidlabs.R
 
 import kotlinx.coroutines.launch
 
-class HotelViewModel(val database: AppDatabase): ViewModel() {
+class HotelViewModel(private val hotelRepository: HotelRepository): ViewModel() {
     var name = mutableStateOf("")
     val price = mutableStateOf("")
     val location = mutableStateOf("")
     val stars = mutableStateOf("")
     val info = mutableStateOf("")
     val img = mutableStateOf(R.drawable.img)
-    val HotelList = database.hotelDao().getAllHotelss()
+    val HotelList = hotelRepository.call().cachedIn(viewModelScope)
     var hotel: Hotel? = null
 
     fun insertHotel() = viewModelScope.launch {
@@ -32,29 +34,18 @@ class HotelViewModel(val database: AppDatabase): ViewModel() {
             stars = stars.value.toInt(),
             info = info.value
         )
-        database.hotelDao().insert(hotel)
+        hotelRepository.insertHotel(hotel)
     }
 
     fun deleteHotel(hotel :  Hotel) = viewModelScope.launch {
-        database.hotelDao().delete(hotel)
+        hotelRepository.deleteHotel(hotel)
     }
 
     fun getHotelById(id: Int) = viewModelScope.launch {
-        database.hotelDao().getHotelById(id)
+        hotelRepository.getHotelById(id)
     }
 
     fun UpdateHotel(hotel: Hotel) = viewModelScope.launch {
-        database.hotelDao().update(hotel)
-    }
-
-    companion object{
-        val factory: ViewModelProvider.Factory = object : ViewModelProvider.Factory{
-            override fun <T : ViewModel> create(
-                modelClass: Class<T>,
-                extras: CreationExtras): T {
-                val database = (checkNotNull(extras[APPLICATION_KEY]) as App).database
-                return HotelViewModel(database) as T
-            }
-        }
+        hotelRepository.updateHotel(hotel)
     }
 }

app/src/main/java/com/example/androidlabs/DB/viewModels/OrderViewModel.kt

@@ -10,22 +10,25 @@ import com.example.androidlabs.App
 import com.example.androidlabs.DB.AppDatabase
 import com.example.androidlabs.DB.models.Hotel
 import com.example.androidlabs.DB.models.Order
+import com.example.androidlabs.DB.models.UserWithOrder
+import com.example.androidlabs.DB.repository.OrderRepository
 import com.example.androidlabs.GlobalUser
+import kotlinx.coroutines.flow.Flow
 import kotlinx.coroutines.launch
 import java.util.Date
 
-class OrderViewModel(val database: AppDatabase) : ViewModel() {
+class OrderViewModel(private val orderRepository: OrderRepository) : ViewModel() {
     var selectedItem: Hotel? = null
     val rooms = mutableStateOf("")
     var dateFrom = mutableStateOf("")
     var dateTo = mutableStateOf("")
 
     fun deleteOrder(order: Order) = viewModelScope.launch {
-        database.orderDao().delete(order)
+        orderRepository.delete(order)
     }
 
-    fun getOrderList(id: Int) = viewModelScope.launch {
-        database.userDao().getUserOrders(id)
+    fun getOrderList(id: Int) : Flow<UserWithOrder> {
+        return orderRepository.getUserOrders(id)
     }
 
 
@@ -42,7 +45,7 @@ class OrderViewModel(val database: AppDatabase) : ViewModel() {
             hotel = selectedItem!!
         )
 
-        val orderId = database.orderDao().createOrder(order)
+        val orderId = orderRepository.createOrder(order)
 
 
         rooms.value = ""
@@ -52,16 +55,4 @@ class OrderViewModel(val database: AppDatabase) : ViewModel() {
     fun getSubTotal(): Double {
         return selectedItem!!.price * rooms.value.toInt()
     }
-
-    companion object{
-        val factory: ViewModelProvider.Factory = object : ViewModelProvider.Factory{
-            override fun <T : ViewModel> create(
-                modelClass: Class<T>,
-                extras: CreationExtras
-            ): T {
-                val database = (checkNotNull(extras[ViewModelProvider.AndroidViewModelFactory.APPLICATION_KEY]) as App).database
-                return OrderViewModel(database) as T
-            }
-        }
-    }
 }

app/src/main/java/com/example/androidlabs/DB/viewModels/UserViewModel.kt

@@ -10,10 +10,11 @@ import com.example.androidlabs.App
 import com.example.androidlabs.DB.AppDatabase
 import com.example.androidlabs.DB.models.RoleEnum
 import com.example.androidlabs.DB.models.User
+import com.example.androidlabs.DB.repository.UserRepository
 import com.example.androidlabs.GlobalUser
 
 import kotlinx.coroutines.launch
-class UserViewModel(val database: AppDatabase): ViewModel() {
+class UserViewModel(private val userRepository: UserRepository): ViewModel() {
 
     var name = mutableStateOf("")
     val surname = mutableStateOf("")
@@ -27,10 +28,10 @@ class UserViewModel(val database: AppDatabase): ViewModel() {
             password = password.value,
             role = RoleEnum.User
         )
-        database.userDao().createUser(user)
+        userRepository.createUser(user)
     }
     fun authUser() = viewModelScope.launch {
-        val user = database.userDao().getUserByEmail(email.value)
+        val user = userRepository.getUserByEmail(email.value)
         if (password.value != "" && user.password == password.value) {
             val globalUser = GlobalUser.getInstance()
             globalUser.setUser(user)
@@ -43,15 +44,4 @@ class UserViewModel(val database: AppDatabase): ViewModel() {
         return android.util.Patterns.EMAIL_ADDRESS.matcher(email).matches()
     }
 
-    companion object{
-        val factory: ViewModelProvider.Factory = object : ViewModelProvider.Factory{
-            override fun <T : ViewModel> create(
-                modelClass: Class<T>,
-                extras: CreationExtras
-            ): T {
-                val database = (checkNotNull(extras[ViewModelProvider.AndroidViewModelFactory.APPLICATION_KEY]) as App).database
-                return UserViewModel(database) as T
-            }
-        }
-    }
 }

app/src/main/java/com/example/androidlabs/Hotel.kt

@@ -1,11 +0,0 @@
-package com.example.androidlabs
-
-
-data class Hotel(
-    val name: String,
-    val img: Int,
-    val stars: Int,
-    val location: String,
-    val info: String,
-    val price: Int,
-)

app/src/main/java/com/example/androidlabs/MyOrderScreen/MyOrderScreen.kt

@@ -22,9 +22,9 @@ import androidx.compose.runtime.getValue
 
 @Composable
 fun MyOrderScreen(orderViewModel: OrderViewModel) {
-    val userWithOrder by orderViewModel.database.userDao().getUserOrders(GlobalUser.getInstance().getUser()?.userId!!).collectAsState(null)
-
-    val orderList: List<Order>? = userWithOrder?.orders
+//    val userWithOrder by orderViewModel.database.userDao().getUserOrders(GlobalUser.getInstance().getUser()?.userId!!).collectAsState(null)
+    val userId = GlobalUser.getInstance().getUser()?.userId
+    val userWithOrder = orderViewModel.getOrderList(userId!!).collectAsState(null).value?.orders
     println()
     Column(
         modifier = Modifier
@@ -46,8 +46,8 @@ fun MyOrderScreen(orderViewModel: OrderViewModel) {
                 modifier = Modifier
                     .fillMaxSize()
             ) {
-                if (orderList != null) {
-                    for (item in orderList) {
+                if (userWithOrder != null) {
+                    for (item in userWithOrder) {
                         OrderCard(item, orderViewModel)
                     }
                 }

app/src/main/java/com/example/androidlabs/Navigation/NavController.kt

@@ -6,6 +6,7 @@ import androidx.navigation.NavHostController
 import androidx.navigation.compose.NavHost
 import androidx.navigation.compose.composable
 import com.example.androidlabs.DB.models.Hotel
+import com.example.androidlabs.DB.viewModels.AppViewModelProvider
 import com.example.androidlabs.DB.viewModels.OrderViewModel
 import com.example.androidlabs.MyOrderScreen.MyOrderScreen
 import com.example.androidlabs.booking.BookingScreen
@@ -23,7 +24,7 @@ import com.google.gson.Gson
 
 @Composable
 fun NavController(navController: NavHostController) {
-    var orderViewModel: OrderViewModel = viewModel(factory = OrderViewModel.factory)
+    var orderViewModel: OrderViewModel = viewModel(factory = AppViewModelProvider.Factory)
     NavHost(
         navController = navController,
         startDestination = NavItem.Home.route

app/src/main/java/com/example/androidlabs/adminPanel/AddPanel.kt

@@ -43,12 +43,13 @@ import androidx.compose.ui.unit.sp
 import androidx.lifecycle.viewmodel.compose.viewModel
 import androidx.navigation.NavHostController
 import com.example.androidlabs.DB.models.PhotoManager
+import com.example.androidlabs.DB.viewModels.AppViewModelProvider
 import com.example.androidlabs.DB.viewModels.HotelViewModel
 import com.example.androidlabs.R
 
 
 @Composable
-fun AddPanel(navHostController: NavHostController, hotelViewModel: HotelViewModel = viewModel(factory = HotelViewModel.factory)){
+fun AddPanel(navHostController: NavHostController, hotelViewModel: HotelViewModel = viewModel(factory = AppViewModelProvider.Factory)){
     val photoManager = PhotoManager()
     Row(
         modifier = Modifier

app/src/main/java/com/example/androidlabs/adminPanel/CardHotelForChange.kt

@@ -31,13 +31,14 @@ import androidx.lifecycle.viewmodel.compose.viewModel
 import androidx.navigation.NavHostController
 import androidx.navigation.compose.rememberNavController
 import com.example.androidlabs.DB.models.Hotel
+import com.example.androidlabs.DB.viewModels.AppViewModelProvider
 import com.example.androidlabs.DB.viewModels.HotelViewModel
 import com.example.androidlabs.R
 import com.google.gson.Gson
 
 
 @Composable
-fun CardHotelForChange(item: Hotel, navController: NavHostController, hotelViewModel: HotelViewModel = viewModel(factory = HotelViewModel.factory)) {
+fun CardHotelForChange(item: Hotel, navController: NavHostController, hotelViewModel: HotelViewModel = viewModel(factory = AppViewModelProvider.Factory)) {
     Row(
         modifier = Modifier
             .fillMaxWidth()

app/src/main/java/com/example/androidlabs/adminPanel/ChangeHotel.kt

@@ -39,10 +39,11 @@ import com.example.androidlabs.DB.models.Hotel
 import com.example.androidlabs.DB.viewModels.HotelViewModel
 import androidx.lifecycle.viewmodel.compose.viewModel
 import com.example.androidlabs.DB.models.PhotoManager
+import com.example.androidlabs.DB.viewModels.AppViewModelProvider
 import com.example.androidlabs.R
 
 @Composable
-fun ChangeHotel(hotel: Hotel, onBackClick: () -> Unit, hotelViewModel: HotelViewModel = viewModel(factory = HotelViewModel.factory)) {
+fun ChangeHotel(hotel: Hotel, onBackClick: () -> Unit, hotelViewModel: HotelViewModel = viewModel(factory = AppViewModelProvider.Factory)) {
     val name = remember { mutableStateOf(hotel.name) }
     val price = remember{ mutableStateOf(hotel.price.toString()) }
     val stars = remember{ mutableStateOf(hotel.stars.toString()) }

app/src/main/java/com/example/androidlabs/adminPanel/ChangePanel.kt

@@ -14,14 +14,14 @@ import androidx.compose.ui.graphics.Color
 import androidx.compose.ui.unit.dp
 import androidx.lifecycle.viewmodel.compose.viewModel
 import androidx.navigation.NavHostController
+import androidx.paging.compose.collectAsLazyPagingItems
+import com.example.androidlabs.DB.viewModels.AppViewModelProvider
 import com.example.androidlabs.DB.viewModels.HotelViewModel
-import com.example.androidlabs.Hotel
-import com.example.androidlabs.R
 
 
 @Composable
-fun ChangePanel(navHostController: NavHostController, hotelViewModel: HotelViewModel = viewModel(factory = HotelViewModel.factory)){
-    val list = hotelViewModel.HotelList.collectAsState(initial = emptyList()).value
+fun ChangePanel(navHostController: NavHostController, hotelViewModel: HotelViewModel = viewModel(factory = AppViewModelProvider.Factory)){
+    val list = hotelViewModel.HotelList.collectAsLazyPagingItems()
     Column(
         modifier = Modifier
             .fillMaxSize()
@@ -33,11 +33,12 @@ fun ChangePanel(navHostController: NavHostController, hotelViewModel: HotelViewM
                 modifier = Modifier
                     .fillMaxSize()
             ) {
-                itemsIndexed(list
-                ){_, item->
-                    CardHotelForChange(item = item, navHostController)
+                items(list.itemCount) { index ->
+                    list[index]?.let { hotel ->
+                    CardHotelForChange(item = hotel, navHostController)
                 }
             }
         }
     }
+}
 }

app/src/main/java/com/example/androidlabs/homeScreen/HomeScreen.kt

@@ -1,6 +1,5 @@
 package com.example.androidlabs.homeScreen
 
-import android.util.Log
 import androidx.compose.foundation.background
 import androidx.compose.foundation.layout.Arrangement
 import androidx.compose.foundation.layout.Box
@@ -8,7 +7,8 @@ import androidx.compose.foundation.layout.Column
 import androidx.compose.foundation.layout.fillMaxHeight
 import androidx.compose.foundation.layout.fillMaxSize
 import androidx.compose.foundation.layout.padding
-import androidx.compose.foundation.lazy.LazyColumn
+import androidx.compose.foundation.lazy.grid.GridCells
+import androidx.compose.foundation.lazy.grid.LazyVerticalGrid
 import androidx.compose.foundation.rememberScrollState
 import androidx.compose.foundation.verticalScroll
 import androidx.compose.material.Text
@@ -17,7 +17,6 @@ import androidx.compose.runtime.collectAsState
 import androidx.compose.ui.Alignment
 import androidx.compose.ui.Modifier
 import androidx.compose.ui.graphics.Color
-import androidx.compose.ui.platform.LocalContext
 import androidx.compose.ui.res.colorResource
 import androidx.compose.ui.text.font.FontWeight
 import androidx.compose.ui.tooling.preview.Preview
@@ -26,17 +25,18 @@ import androidx.compose.ui.unit.sp
 import androidx.lifecycle.viewmodel.compose.viewModel
 import androidx.navigation.NavHostController
 import androidx.navigation.compose.rememberNavController
-import com.example.androidlabs.DB.AppDatabase
+import androidx.paging.compose.collectAsLazyPagingItems
+import androidx.paging.compose.itemKey
+import com.example.androidlabs.DB.models.Hotel
+import com.example.androidlabs.DB.viewModels.AppViewModelProvider
 import com.example.androidlabs.DB.viewModels.HotelViewModel
 import com.example.androidlabs.R
 import com.example.androidlabs.homeScreen.CardItem.HotelCard
-import com.example.androidlabs.Hotel
 import com.example.androidlabs.homeScreen.SearchField.SearchField
-import kotlinx.coroutines.flow.count
 
 @Composable
-fun HomeScreen(navController: NavHostController, hotelViewModel: HotelViewModel = viewModel(factory = HotelViewModel.factory)) {
-    val list = hotelViewModel.HotelList.collectAsState(initial = emptyList()).value
+fun HomeScreen(navController: NavHostController, hotelViewModel: HotelViewModel = viewModel(factory = AppViewModelProvider.Factory)) {
+    val list = hotelViewModel.HotelList.collectAsLazyPagingItems()
     //Log.d("MyLog", list.toString())
     Column(
         modifier = Modifier
@@ -68,12 +68,22 @@ fun HomeScreen(navController: NavHostController, hotelViewModel: HotelViewModel
         }
         Column (
             modifier = Modifier
-                .verticalScroll(rememberScrollState())
+                //.verticalScroll(rememberScrollState())
             .padding(bottom = 60.dp)
 
         ){
-            for (item in list){
-                HotelCard(item, navController)
+            LazyVerticalGrid(
+                columns = GridCells.Fixed(1)
+            ) {
+                items(
+                    count = list.itemCount,
+                    key = list.itemKey { hotel -> hotel.hotelId!! }
+                ) { index: Int ->
+                    val hotel: Hotel? = list[index]
+                    if (hotel != null) {
+                        HotelCard(hotel, navController)
+                    }
+                }
             }
 
         }

app/src/main/java/com/example/androidlabs/profileScreen/signIn/SignInCard.kt

@@ -40,11 +40,12 @@ import androidx.compose.ui.unit.sp
 import androidx.lifecycle.viewmodel.compose.viewModel
 import androidx.navigation.NavHostController
 import androidx.navigation.compose.rememberNavController
+import com.example.androidlabs.DB.viewModels.AppViewModelProvider
 import com.example.androidlabs.DB.viewModels.UserViewModel
 import com.example.androidlabs.R
 
 @Composable
-fun SignInCard(navController: NavHostController, userViewModel: UserViewModel = viewModel(factory = UserViewModel.factory)) {
+fun SignInCard(navController: NavHostController, userViewModel: UserViewModel = viewModel(factory = AppViewModelProvider.Factory)) {
     Row(
         modifier = Modifier
             .fillMaxWidth()

app/src/main/java/com/example/androidlabs/profileScreen/signUp/SignUpCard.kt

@@ -37,12 +37,13 @@ import androidx.compose.ui.unit.sp
 import androidx.lifecycle.viewmodel.compose.viewModel
 import androidx.navigation.NavHostController
 import androidx.navigation.compose.rememberNavController
+import com.example.androidlabs.DB.viewModels.AppViewModelProvider
 import com.example.androidlabs.DB.viewModels.UserViewModel
 import com.example.androidlabs.R
 import com.example.androidlabs.profileScreen.signIn.LoginScreen
 
 @Composable
-fun SignUpCard(navHostController: NavHostController, userViewModel: UserViewModel = viewModel(factory = UserViewModel.factory)) {
+fun SignUpCard(navHostController: NavHostController, userViewModel: UserViewModel = viewModel(factory = AppViewModelProvider.Factory)) {
     Row(
         modifier = Modifier
             .fillMaxWidth()