ViewModel에 인수 전달 (Hilt)
이 레시피에서는 종속 항목 삽입을 위해 Hilt를 사용하여 탐색 인수 (키)를 ViewModel에 전달하는 방법을 보여줍니다.
작동 방식
이 예에서는 Dagger/Hilt의 지원 삽입 기능을 사용합니다.
ViewModel에는@HiltViewModel주석이 달려 있고 생성자는@AssistedInject를 사용하여 탐색 키 (@Assisted주석이 달려 있음)를 수신합니다.ViewModel을 만들기 위해@AssistedFactory인터페이스가 정의됩니다.hiltViewModel컴포저블 함수는ViewModel인스턴스를 가져오는 데 사용됩니다. 탐색 키를 팩토리로 전달하여ViewModel에서 사용할 수 있도록creationCallback가 제공됩니다.
참고: rememberViewModelStoreNavEntryDecorator는 NavDisplay의 entryDecorators에 추가됩니다. 이렇게 하면 ViewModel가 해당 NavEntry에 올바르게 범위가 지정되어 각 고유 탐색 키에 새 ViewModel 인스턴스가 생성됩니다.
/* * Copyright 2025 The Android Open Source Project * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package com.example.nav3recipes.passingarguments.viewmodels.hilt import android.os.Bundle import androidx.activity.ComponentActivity import androidx.activity.compose.setContent import androidx.compose.foundation.lazy.LazyColumn import androidx.compose.material3.Button import androidx.compose.material3.Text import androidx.compose.runtime.Composable import androidx.compose.runtime.mutableStateListOf import androidx.compose.runtime.remember import androidx.hilt.lifecycle.viewmodel.compose.hiltViewModel import androidx.lifecycle.ViewModel import androidx.lifecycle.compose.dropUnlessResumed import androidx.lifecycle.viewmodel.navigation3.rememberViewModelStoreNavEntryDecorator import androidx.navigation3.runtime.entryProvider import androidx.navigation3.runtime.rememberSaveableStateHolderNavEntryDecorator import androidx.navigation3.ui.NavDisplay import com.example.nav3recipes.content.ContentBlue import com.example.nav3recipes.content.ContentGreen import com.example.nav3recipes.passingarguments.viewmodels.basic.RouteB import com.example.nav3recipes.ui.setEdgeToEdgeConfig import dagger.assisted.Assisted import dagger.assisted.AssistedFactory import dagger.assisted.AssistedInject import dagger.hilt.android.AndroidEntryPoint import dagger.hilt.android.lifecycle.HiltViewModel data object RouteA data class RouteB(val id: String) @AndroidEntryPoint class HiltViewModelsActivity : ComponentActivity() { override fun onCreate(savedInstanceState: Bundle?) { setEdgeToEdgeConfig() super.onCreate(savedInstanceState) setContent { val backStack = remember { mutableStateListOf<Any>(RouteA) } NavDisplay( backStack = backStack, onBack = { backStack.removeLastOrNull() }, // In order to add the `ViewModelStoreNavEntryDecorator` (see comment below for why) // we also need to add the default `NavEntryDecorator`s as well. These provide // extra information to the entry's content to enable it to display correctly // and save its state. entryDecorators = listOf( rememberSaveableStateHolderNavEntryDecorator(), rememberViewModelStoreNavEntryDecorator() ), entryProvider = entryProvider { entry<RouteA> { ContentGreen("Welcome to Nav3") { LazyColumn { items(10) { i -> Button(onClick = dropUnlessResumed { backStack.add(RouteB("$i")) }) { Text("$i") } } } } } entry<RouteB> { key -> val viewModel = hiltViewModel<RouteBViewModel, RouteBViewModel.Factory>( // Note: We need a new ViewModel for every new RouteB instance. Usually // we would need to supply a `key` String that is unique to the // instance, however, the ViewModelStoreNavEntryDecorator (supplied // above) does this for us, using `NavEntry.contentKey` to uniquely // identify the viewModel. // // tl;dr: Make sure you use rememberViewModelStoreNavEntryDecorator() // if you want a new ViewModel for each new navigation key instance. creationCallback = { factory -> factory.create(key) } ) ScreenB(viewModel = viewModel) } } ) } } } @Composable fun ScreenB(viewModel: RouteBViewModel) { ContentBlue("Route id: ${viewModel.navKey.id} ") } @HiltViewModel(assistedFactory = RouteBViewModel.Factory::class) class RouteBViewModel @AssistedInject constructor( @Assisted val navKey: RouteB ) : ViewModel() { @AssistedFactory interface Factory { fun create(navKey: RouteB): RouteBViewModel } }
ViewModel에 인수 전달 (기본)
이 레시피는 맞춤 ViewModelProvider.Factory를 사용하여 탐색 인수 (키)를 ViewModel에 전달하는 방법을 보여줍니다.
작동 방식
- 탐색 키를 생성자 매개변수로 사용하는 맞춤
ViewModelProvider.Factory가 생성됩니다. entry컴포저블 내에서viewModel(factory = ...)은ViewModel인스턴스를 만드는 데 사용되며 현재 탐색 키를 팩토리에 전달합니다. 이렇게 하면 탐색 키를ViewModel에서 사용할 수 있습니다.
참고: rememberViewModelStoreNavEntryDecorator는 NavDisplay의 entryDecorators에 추가됩니다. 이렇게 하면 ViewModel가 해당 NavEntry에 올바르게 범위가 지정되어 각 고유 탐색 키에 새 ViewModel 인스턴스가 생성됩니다.
/* * Copyright 2025 The Android Open Source Project * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package com.example.nav3recipes.passingarguments.viewmodels.basic import android.os.Bundle import androidx.activity.ComponentActivity import androidx.activity.compose.setContent import androidx.compose.foundation.lazy.LazyColumn import androidx.compose.material3.Button import androidx.compose.material3.Text import androidx.compose.runtime.Composable import androidx.compose.runtime.mutableStateListOf import androidx.compose.runtime.remember import androidx.lifecycle.ViewModel import androidx.lifecycle.ViewModelProvider import androidx.lifecycle.compose.dropUnlessResumed import androidx.lifecycle.viewmodel.compose.viewModel import androidx.lifecycle.viewmodel.navigation3.rememberViewModelStoreNavEntryDecorator import androidx.navigation3.runtime.entryProvider import androidx.navigation3.runtime.rememberSaveableStateHolderNavEntryDecorator import androidx.navigation3.ui.NavDisplay import com.example.nav3recipes.content.ContentBlue import com.example.nav3recipes.content.ContentGreen import com.example.nav3recipes.ui.setEdgeToEdgeConfig data object RouteA data class RouteB(val id: String) class BasicViewModelsActivity : ComponentActivity() { override fun onCreate(savedInstanceState: Bundle?) { setEdgeToEdgeConfig() super.onCreate(savedInstanceState) setContent { val backStack = remember { mutableStateListOf<Any>(RouteA) } NavDisplay( backStack = backStack, onBack = { backStack.removeLastOrNull() }, // In order to add the `ViewModelStoreNavEntryDecorator` (see comment below for why) // we also need to add the default `NavEntryDecorator`s as well. These provide // extra information to the entry's content to enable it to display correctly // and save its state. entryDecorators = listOf( rememberSaveableStateHolderNavEntryDecorator(), rememberViewModelStoreNavEntryDecorator() ), entryProvider = entryProvider { entry<RouteA> { ContentGreen("Welcome to Nav3") { LazyColumn { items(10) { i -> Button(onClick = dropUnlessResumed { backStack.add(RouteB("$i")) }) { Text("$i") } } } } } entry<RouteB> { key -> // Note: We need a new ViewModel for every new RouteB instance. Usually // we would need to supply a `key` String that is unique to the // instance, however, the ViewModelStoreNavEntryDecorator (supplied // above) does this for us, using `NavEntry.contentKey` to uniquely // identify the viewModel. // // tl;dr: Make sure you use rememberViewModelStoreNavEntryDecorator() // if you want a new ViewModel for each new navigation key instance. ScreenB(viewModel = viewModel(factory = RouteBViewModel.Factory(key))) } } ) } } } @Composable fun ScreenB(viewModel: RouteBViewModel = viewModel()) { ContentBlue("Route id: ${viewModel.key.id} ") } class RouteBViewModel( val key: RouteB ) : ViewModel() { class Factory( private val key: RouteB, ) : ViewModelProvider.Factory { override fun <T : ViewModel> create(modelClass: Class<T>): T { return RouteBViewModel(key) as T } } }
ViewModel에 인수 전달 (Koin)
이 레시피에서는 종속 항목 삽입을 위해 Koin을 사용하여 탐색 인수 (키)를 ViewModel에 전달하는 방법을 보여줍니다.
작동 방식
ViewModel를 제공하는 Koin 모듈이 정의됩니다.koinViewModel컴포저블 함수는ViewModel인스턴스를 가져오는 데 사용됩니다.- 탐색 키는
parametersOf(key)을 사용하여ViewModel의 생성자에 전달됩니다. 이렇게 하면 탐색 키를ViewModel에서 사용할 수 있습니다.
참고: rememberViewModelStoreNavEntryDecorator는 NavDisplay의 entryDecorators에 추가됩니다. 이렇게 하면 ViewModel가 해당 NavEntry에 올바르게 범위가 지정되어 각 고유 탐색 키에 새 ViewModel 인스턴스가 생성됩니다.
package com.example.nav3recipes.passingarguments.viewmodels.koin import android.os.Bundle import androidx.activity.ComponentActivity import androidx.activity.compose.setContent import androidx.compose.foundation.lazy.LazyColumn import androidx.compose.material3.Button import androidx.compose.material3.Text import androidx.compose.runtime.Composable import androidx.compose.runtime.mutableStateListOf import androidx.compose.runtime.remember import androidx.lifecycle.ViewModel import androidx.lifecycle.compose.dropUnlessResumed import androidx.lifecycle.viewmodel.navigation3.rememberViewModelStoreNavEntryDecorator import androidx.navigation3.runtime.entryProvider import androidx.navigation3.runtime.rememberSaveableStateHolderNavEntryDecorator import androidx.navigation3.ui.NavDisplay import com.example.nav3recipes.content.ContentBlue import com.example.nav3recipes.content.ContentGreen import com.example.nav3recipes.ui.setEdgeToEdgeConfig import org.koin.compose.KoinApplication import org.koin.compose.viewmodel.koinViewModel import org.koin.core.module.dsl.viewModelOf import org.koin.core.parameter.parametersOf import org.koin.dsl.koinConfiguration import org.koin.dsl.module data object RouteA data class RouteB(val id: String) class KoinViewModelsActivity : ComponentActivity() { override fun onCreate(savedInstanceState: Bundle?) { setEdgeToEdgeConfig() super.onCreate(savedInstanceState) setContent { val backStack = remember { mutableStateListOf<Any>(RouteA) } // Koin Compose Entry point KoinApplication( configuration = koinConfiguration { modules(appModule) } ) { NavDisplay( backStack = backStack, onBack = { backStack.removeLastOrNull() }, // In order to add the `ViewModelStoreNavEntryDecorator` (see comment below for why) // we also need to add the default `NavEntryDecorator`s as well. These provide // extra information to the entry's content to enable it to display correctly // and save its state. entryDecorators = listOf( rememberSaveableStateHolderNavEntryDecorator(), rememberViewModelStoreNavEntryDecorator() ), entryProvider = entryProvider { entry<RouteA> { ContentGreen("Welcome to Nav3") { LazyColumn { items(10) { i -> Button(onClick = dropUnlessResumed { backStack.add(RouteB("$i")) }) { Text("$i") } } } } } entry<RouteB> { key -> val viewModel = koinViewModel<RouteBViewModel> { parametersOf(key) } ScreenB(viewModel = viewModel) } } ) } } } } // Local Koin Module private val appModule = module { viewModelOf(::RouteBViewModel) } @Composable fun ScreenB(viewModel: RouteBViewModel) { ContentBlue("Route id: ${viewModel.navKey.id} ") } class RouteBViewModel(val navKey: RouteB) : ViewModel()