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Я пытаюсь ввести свое navHostController в свою MainActivity рукоятку. Но при попытке скомпилировать код я получаю следующую ошибку:

 > Task :app:kaptDebugKotlin
C:UserspierrAndroidStudioProjectsAndroidAppsComposeUdemycourse01crudappbuildgeneratedsourcekaptdebugcomexamplecrudCrudApplication_HiltComponents.java:129: error: [Dagger/MissingBinding] androidx.navigation.NavHostController cannot be provided without an @Inject constructor or an @Provides-annotated method.
  public abstract static class SingletonC implements CrudApplication_GeneratedInjector,
                         ^
      androidx.navigation.NavHostController is injected at
          com.example.crud.ui.MainActivity.navHostController
      com.example.crud.ui.MainActivity is injected at
          com.example.crud.ui.MainActivity_GeneratedInjector.injectMainActivity(com.example.crud.ui.MainActivity) [com.example.crud.CrudApplication_HiltComponents.SingletonC ? com.example.crud.CrudApplication_HiltComponents.ActivityRetainedC ? com.example.crud.CrudApplication_HiltComponents.ActivityC]

> Task :app:kaptDebugKotlin FAILED

FAILURE: Build failed with an exception.

* What went wrong:
Execution failed for task ':app:kaptDebugKotlin'.
> A failure occurred while executing org.jetbrains.kotlin.gradle.internal.KaptWithoutKotlincTask$KaptExecutionWorkAction
   > java.lang.reflect.InvocationTargetException (no error message)

* Try:
Run with --stacktrace option to get the stack trace. Run with --info or --debug option to get more log output. Run with --scan to get full insights.

* Get more help at https://help.gradle.org

Deprecated Gradle features were used in this build, making it incompatible with Gradle 8.0.
Use '--warning-mode all' to show the individual deprecation warnings.
See https://docs.gradle.org/7.0.2/userguide/command_line_interface.html#sec:command_line_warnings

BUILD FAILED in 5s
24 actionable tasks: 2 executed, 22 up-to-date

 

Это мой MainActivity код:

 package com.example.crud.ui

import android.os.Bundle
import androidx.activity.ComponentActivity
import androidx.activity.compose.setContent
import androidx.compose.material.MaterialTheme
import androidx.compose.material.Surface
import androidx.navigation.NavHostController
import com.example.crud.navigation.NavigationComponent
import com.example.crud.ui.theme.CRUDTheme
import dagger.hilt.android.AndroidEntryPoint
import javax.inject.Inject

@AndroidEntryPoint
class MainActivity : ComponentActivity() {

    @Inject lateinit var navHostController: NavHostController

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)

        setContent {
            CRUDTheme {
                Surface(color = MaterialTheme.colors.background) {
                    NavigationComponent(navHostController)
                }
            }
        }
    }
}
 

Это мой NavigationModule код:

 package com.example.crud.di

import androidx.compose.runtime.Composable
import androidx.navigation.compose.rememberNavController
import dagger.Module
import dagger.hilt.InstallIn
import dagger.hilt.android.components.ActivityComponent

@Module
@InstallIn(ActivityComponent::class)
object NavigationModule {
    @Composable
    fun provideNavHostController() = rememberNavController()
}
 

This is the code for the NavigationComponent (it takes as a parameter the navHostController I’m trying to inject into MainActivity ):

 package com.example.crud.navigation

import androidx.compose.runtime.Composable
import androidx.compose.runtime.livedata.observeAsState
import androidx.hilt.navigation.compose.hiltViewModel
import androidx.navigation.NavHostController
import androidx.navigation.NavType
import androidx.navigation.compose.NavHost
import androidx.navigation.compose.composable
import androidx.navigation.navArgument
import com.example.crud.ui.screens.crud.details.DetailScreen
import com.example.crud.ui.screens.crud.register.RegisterScreen
import com.example.crud.ui.screens.home.HomeScreen
import com.example.crud.ui.screens.home.HomeViewModel

@Composable
fun NavigationComponent(navController: NavHostController) {
    NavHost(navController = navController, startDestination = Routes.HOME) {
        composable(Routes.HOME) {
            val homeViewModel: HomeViewModel = hiltViewModel()
            val cities = homeViewModel.cities.observeAsState(listOf())
            HomeScreen(
                cities = cities,
                navigateToDetailsAction = { navController.navigate(Routes.REGISTER) }
            ) { cityId ->
                navController.navigate(Routes.getDetailsDynamicRoute(cityId))
            }
        }
        composable(Routes.REGISTER) { RegisterScreen { navController.popBackStack() } }
        composable(
            route = Routes.DETAILS,
            arguments = listOf(navArgument(Routes.CITY_ID_KEY) { type = NavType.IntType })
        ) { backStackEntry ->
            val cityId = backStackEntry.arguments?.getInt(Routes.CITY_ID_KEY)
            cityId?.let {
                DetailScreen(cityId = it, popNavigation = { navController.popBackStack() })
            }
        }
    }
}
 

Я считаю, что это не имеет отношения к решению проблемы, но код в Routes.kt файле следующий:

 package com.example.crud.navigation

object Routes {
    private const val DETAILS_BASE_ROUTE = "details/"
    const val HOME = "home"
    const val REGISTER = "register"
    const val CITY_ID_KEY = "cityId"
    const val DETAILS = "$DETAILS_BASE_ROUTE{$CITY_ID_KEY}"

    fun getDetailsDynamicRoute(cityId: Int) = "$DETAILS_BASE_ROUTE${cityId}"
}
 

Что я делаю не так?

но я думаю, что вам не нужно создавать NavController в основном классе, так как эта часть компонента навигации класса la, я думал, что этот класс отвечает за обработку этого.

Я новичок в мире Android, но для меня имеет смысл, что компонент навигации управляет навигационным контроллером и всеми его взаимодействиями с ним.

Обычно я использую его таким образом

 @Composable fun NavigationHost() {

val navController = rememberNavController()

MyTheme {
    NavHost(
        navController = navController,
        NavItem.Main.route
    )
    {

        composable(route = NavItem.Main.route) {
            FeedScreen { productOnClick ->
                navController.navigate(NavItem.Detail.createNavRoute(productOnClick.id))
            }
        }

        composable(route = NavItem.Main.route) {
            ConfirmationScreen {
                navController.navigate(NavItem.Main.route)
            }
        }
    }

}
 

}