Hi folks iam facing this issue while connecting to the room kotlinlang #android

Hi folks , iam facing this issue while connecting ...

Binod Basnet

04/07/2024, 8:10 AM

Hi folks , iam facing this issue while connecting to the room database using compose in android studio iguana version java.lang.NullPointerException at androidx.room.Room.getGeneratedImplementation(Room.kt:42) at androidx.room.RoomDatabase$Builder.build(RoomDatabase.kt:1351 This is my app gradle build

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plugins {
    alias(libs.plugins.androidApplication)
    alias(libs.plugins.jetbrainsKotlinAndroid)
    id("kotlin-kapt")
}




android {
    namespace = "com.binod.myexpensetracker"
    compileSdk = 34

    defaultConfig {
        applicationId = "com.binod.myexpensetracker"
        minSdk = 24
        targetSdk = 34
        versionCode = 1
        versionName = "1.0"

        testInstrumentationRunner = "androidx.test.runner.AndroidJUnitRunner"
        vectorDrawables {
            useSupportLibrary = true
        }
    }

    buildTypes {
        release {
            isMinifyEnabled = false
            proguardFiles(
                getDefaultProguardFile("proguard-android-optimize.txt"),
                "<http://proguard-rules.pro|proguard-rules.pro>"
            )
        }
    }
    compileOptions {
        sourceCompatibility = JavaVersion.VERSION_1_8
        targetCompatibility = JavaVersion.VERSION_1_8
    }
    kotlinOptions {
        jvmTarget = "1.8"
    }
    buildFeatures {
        compose = true
    }
    composeOptions {
        kotlinCompilerExtensionVersion = "1.5.1"
    }
    packaging {
        resources {
            excludes += "/META-INF/{AL2.0,LGPL2.1}"
        }
    }
}

dependencies {

    implementation(libs.androidx.core.ktx)
    implementation(libs.androidx.lifecycle.runtime.ktx)
    implementation(libs.androidx.activity.compose)
    implementation(platform(libs.androidx.compose.bom))
    implementation(libs.androidx.ui)
    implementation(libs.androidx.ui.graphics)
    implementation(libs.androidx.ui.tooling.preview)
    implementation(libs.androidx.material3)
    implementation(libs.androidx.navigation.runtime.ktx)
    implementation(libs.androidx.navigation.compose)
    implementation(libs.androidx.room.common)
    implementation(libs.androidx.room.ktx)
    implementation(libs.androidx.lifecycle.livedata.ktx)
    testImplementation(libs.junit)
    androidTestImplementation(libs.androidx.junit)
    androidTestImplementation(libs.androidx.espresso.core)
    androidTestImplementation(platform(libs.androidx.compose.bom))
    androidTestImplementation(libs.androidx.ui.test.junit4)
    debugImplementation(libs.androidx.ui.tooling)
    debugImplementation(libs.androidx.ui.test.manifest)
}

This is my project gradle build

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// Top-level build file where you can add configuration options common to all sub-projects/modules.
plugins {
    alias(libs.plugins.androidApplication) apply false
    alias(libs.plugins.jetbrainsKotlinAndroid) apply false
}

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[versions]
agp = "8.3.1"
kotlin = "1.9.0"
coreKtx = "1.12.0"
junit = "4.13.2"
junitVersion = "1.1.5"
espressoCore = "3.5.1"
lifecycleRuntimeKtx = "2.7.0"
activityCompose = "1.8.2"
composeBom = "2024.03.00"
navigationRuntimeKtx = "2.7.7"
navigationCompose = "2.7.7"
roomCommon = "2.6.1"
roomKtx = "2.6.1"
lifecycleLivedataKtx = "2.7.0"

[libraries]
androidx-core-ktx = { group = "androidx.core", name = "core-ktx", version.ref = "coreKtx" }
junit = { group = "junit", name = "junit", version.ref = "junit" }
androidx-junit = { group = "androidx.test.ext", name = "junit", version.ref = "junitVersion" }
androidx-espresso-core = { group = "androidx.test.espresso", name = "espresso-core", version.ref = "espressoCore" }
androidx-lifecycle-runtime-ktx = { group = "androidx.lifecycle", name = "lifecycle-runtime-ktx", version.ref = "lifecycleRuntimeKtx" }
androidx-activity-compose = { group = "androidx.activity", name = "activity-compose", version.ref = "activityCompose" }
androidx-compose-bom = { group = "androidx.compose", name = "compose-bom", version.ref = "composeBom" }
androidx-ui = { group = "androidx.compose.ui", name = "ui" }
androidx-ui-graphics = { group = "androidx.compose.ui", name = "ui-graphics" }
androidx-ui-tooling = { group = "androidx.compose.ui", name = "ui-tooling" }
androidx-ui-tooling-preview = { group = "androidx.compose.ui", name = "ui-tooling-preview" }
androidx-ui-test-manifest = { group = "androidx.compose.ui", name = "ui-test-manifest" }
androidx-ui-test-junit4 = { group = "androidx.compose.ui", name = "ui-test-junit4" }
androidx-material3 = { group = "androidx.compose.material3", name = "material3" }
androidx-navigation-runtime-ktx = { group = "androidx.navigation", name = "navigation-runtime-ktx", version.ref = "navigationRuntimeKtx" }
androidx-navigation-compose = { group = "androidx.navigation", name = "navigation-compose", version.ref = "navigationCompose" }
androidx-room-common = { group = "androidx.room", name = "room-common", version.ref = "roomCommon" }
androidx-room-ktx = { group = "androidx.room", name = "room-ktx", version.ref = "roomKtx" }
androidx-lifecycle-livedata-ktx = { group = "androidx.lifecycle", name = "lifecycle-livedata-ktx", version.ref = "lifecycleLivedataKtx" }

[plugins]
androidApplication = { id = "com.android.application", version.ref = "agp" }
jetbrainsKotlinAndroid = { id = "org.jetbrains.kotlin.android", version.ref = "kotlin" }

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@Composable
fun IncomeScreen(navController: NavController) {
    val context = LocalContext.current
    val database = AppDatabase.getDatabase(context)
    val repository = IncomeSourceRepository(database.incomeSourceDao())
    val vm: IncomeViewModel = viewModel(
        factory = IncomeViewModelFactory(repository)
    )


//    vm.insert(IncomeSource("Rent", 14900.3))
//    vm.insert(IncomeSource("Agriculture", 13400.3))
//    vm.insert(IncomeSource("Business", 11400.3))
//    vm.insert(IncomeSource("Freelancing", 14300.3))

}

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@Database(entities = [IncomeSource::class], version = 1, exportSchema = false)
abstract class AppDatabase : RoomDatabase() {
    abstract fun incomeSourceDao(): IncomeSourceDao


    companion object {
        @Volatile
        private var INSTANCE: AppDatabase? = null

        fun getDatabase(context: Context): AppDatabase {
            return INSTANCE ?: synchronized(this) {
                val instance = Room.databaseBuilder(
                    context.applicationContext,
                    AppDatabase::class.java,
                    "income_database"
                ).fallbackToDestructiveMigration().build()
                INSTANCE = instance
                instance
            }
        }
    }
}

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@Entity(tableName = "income_sources")
data class IncomeSource(
    val name: String,
    val amount: Double
) {
    @PrimaryKey(autoGenerate = true)
    var id: Int = 0

}

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@Dao
interface IncomeSourceDao {
    @Query("SELECT * FROM income_sources")
    fun getAll(): Flow<List<IncomeSource>>

    @Insert(onConflict = OnConflictStrategy.REPLACE)
    suspend fun insert(incomeSource: IncomeSource)

    @Delete
    suspend fun delete(incomeSource: IncomeSource)

//    @Query("DELETE FROM income_sources")
//    suspend fun deleteAll()

}

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class IncomeSourceRepository(private val incomeSourceDao: IncomeSourceDao) {
    val allIncomeSources: Flow<List<IncomeSource>> = incomeSourceDao.getAll()

    suspend fun insert(incomeSource: IncomeSource) {
        incomeSourceDao.insert(incomeSource)
    }

    suspend fun delete(incomeSource: IncomeSource) {
        incomeSourceDao.delete(incomeSource)
    }

//    suspend fun deleteAll() {
//        incomeSourceDao.deleteAll()
//    }
}

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class IncomeViewModel(
    private var repository: IncomeSourceRepository
) : ViewModel() {

    val allIncomeSources: LiveData<List<IncomeSource>> = repository.allIncomeSources.asLiveData()


    fun insert(incomeSource: IncomeSource) = viewModelScope.launch {
        repository.insert(incomeSource)
    }

    fun delete(incomeSource: IncomeSource) = viewModelScope.launch {
        repository.delete(incomeSource)
    }

//    fun deleteAll() = viewModelScope.launch {
//        repository.deleteAll()
//    }
}

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class IncomeViewModelFactory(private val repository: IncomeSourceRepository) :
    ViewModelProvider.Factory {
    override fun <T : ViewModel> create(modelClass: Class<T>): T {
        if (modelClass.isAssignableFrom(IncomeViewModel::class.java)) {
            return IncomeViewModel(repository) as T
        }
        throw IllegalArgumentException("Unknown ViewModel class")
    }
}

🧵 3

Chrimaeon

04/07/2024, 8:43 AM

Please post long code snippets in the thread. https://kotlinlang.org/community/slackccugl.html#basic-usage-guidelines

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