无法在kotlin dagger2 mvvm中注入接口

Question

嗨，当我尝试在下面的类中注入Doa接口时，我正在使用mvvm和dagger2

@Singleton
class PodCastRepository @Inject constructor(private val dao: PodCastDao) {
}

我的接口类

interface PodCastDao {

    fun getLegoThemes(): LiveData<PodCast>

}

Answer 1

需要先提供一个数据库。然后在为dao提供的方法中返回dao

例如：

package com.test.demo.db

import androidx.room.Database
import androidx.room.RoomDatabase
import androidx.room.TypeConverters
import com.test.demo.model.entity.Movie
import com.test.demo.model.entity.Article
import com.test.demo.util.StringListConverter

@Database(entities = [Article::class,Movie::class],
    version = 3, exportSchema = false)

@TypeConverters(value = [StringListConverter::class/*, (IntegerListConverter::class),
    (KeywordListConverter::class), (VideoListConverter::class), (ReviewListConverter::class)*/])
abstract class AppDatabase : RoomDatabase() {
    abstract fun movieDao(): MovieDao
    abstract fun peopleDao(): ArticleDao
}



package com.test.demo.di

import android.app.Application
import androidx.annotation.NonNull
import androidx.room.Room
import com.test.demo.db.AppDatabase
import com.test.demo.db.MovieDao
import com.test.demo.db.ArticleDao
import dagger.Module
import dagger.Provides
import javax.inject.Singleton

@Module
class PersistenceModule {

  @Provides
  @Singleton
  fun provideDatabase(@NonNull application: Application): AppDatabase {
    return Room
      .databaseBuilder(application, AppDatabase::class.java, "Demo1.db")
      .allowMainThreadQueries()
      .build()
  }

  @Provides
  @Singleton
  fun provideMovieDao(@NonNull database: AppDatabase): MovieDao {
    return database.movieDao()
  }


  @Provides
  @Singleton
  fun providePeopleDao(@NonNull database: AppDatabase): ArticleDao {
    return database.peopleDao()
  }

}