我对 Hilt 和 ViewModel 有疑问。我收到 RunTimeException:
MainViewModel> has no zero argument constructor
我花了好几个小时才找到问题所在...
以下是我的代码来源:
应用模块:
@Module
@InstallIn(SingletonComponent::class)
object AppModule {
@Singleton
@Provides
fun provideCurrencyApi(): CurrencyApi = Retrofit.Builder()
.baseUrl(BASE_URL)
.addConverterFactory(GsonConverterFactory.create())
.build()
.create(CurrencyApi::class.java)
@Singleton
@Provides
fun provideMainRepository(api: CurrencyApi): MainRepository = DefaultMainRepository(api)
@Singleton
@Provides
fun provideDispatchers(): DispatcherProvider = object : DispatcherProvider {
override val main: CoroutineDispatcher
get() = Dispatchers.Main
override val io: CoroutineDispatcher
get() = Dispatchers.IO
override val default: CoroutineDispatcher
get() = Dispatchers.Default
override val unconfined: CoroutineDispatcher
get() = Dispatchers.Unconfined
}
}
主要活动:
@AndroidEntryPoint
class MainActivity : AppCompatActivity() {
private lateinit var binding: ActivityMainBinding
private val viewModel: MainViewModel by viewModels()
主视图模型:
@HiltViewModel
class MainViewModel @Inject constructor(
private val repository: MainRepository,
private val dispatchers: DispatcherProvider
) : ViewModel() {
主存储库
class DefaultMainRepository @Inject constructor(
private val api: CurrencyApi
) : MainRepository {
Hee 是 Gradle 依赖项:
dependencies {
implementation 'androidx.core:core-ktx:1.7.0'
implementation 'androidx.appcompat:appcompat:1.4.1'
implementation 'com.google.android.material:material:1.5.0'
implementation 'androidx.constraintlayout:constraintlayout:2.1.3'
implementation 'com.squareup.retrofit2:retrofit:2.9.0'
implementation 'com.squareup.retrofit2:converter-gson:2.9.0'
implementation 'com.squareup.okhttp3:okhttp:4.9.0'
implementation "androidx.activity:activity-ktx:1.4.0"
implementation 'com.google.dagger:hilt-android:2.40.5'
kapt 'com.google.dagger:hilt-compiler:2.40.5'
implementation 'androidx.hilt:hilt-lifecycle-viewmodel:1.0.0-alpha03'
kapt'androidx.hilt:hilt-compiler:1.0.0'
implementation 'org.jetbrains.kotlinx:kotlinx-coroutines-core:1.5.2'
implementation 'org.jetbrains.kotlinx:kotlinx-coroutines-android:1.5.2'
implementation 'androidx.lifecycle:lifecycle-viewmodel-ktx:2.4.0'
implementation 'androidx.navigation:navigation-fragment-ktx:2.4.0'
androidTestImplementation 'com.google.dagger:hilt-android-testing:2.40.5'
kaptAndroidTest 'com.google.dagger:hilt-compiler:2.40.5'
testImplementation 'com.google.dagger:hilt-android-testing:2.40.5'
kaptTest 'com.google.dagger:hilt-compiler:2.40.5'
testImplementation 'junit:junit:4.13.2'
androidTestImplementation 'androidx.test.ext:junit:1.1.3'
androidTestImplementation 'androidx.test.espresso:espresso-core:3.4.0'
}
应用:
@HiltAndroidApp
class CurrencyApplication: Application()
清单:
<application
android:name=".CurrencyApplication"
我试图像这里一样到处寻找解决方案:可能的原因
如有任何帮助,我将不胜感激
首先,检查 anotationProcessor 的 hilt 是否能够生成正确的绑定,因此转到 app.gradle 并检查这些依赖项是否存在:
dependencies {
implementation 'com.google.dagger:hilt-android:2.30-alpha'
kapt 'com.google.dagger:hilt-android-compiler:2.30-alpha'
implementation 'androidx.hilt:hilt-lifecycle-viewmodel:1.0.0-alpha02'
kapt'androidx.hilt:hilt-compiler:1.0.0-alpha02'
...
}
您正在使用“kapt hilt-compiler”两次。
我不确定这是个问题,但我正在使用它并且它有效:
... compose_version = '1.3.0-beta02'
... hilt_version = '2.42'
// Hilt
implementation "com.google.dagger:hilt-android:$hilt_version"
kapt "com.google.dagger:hilt-android-compiler:$hilt_version"
kapt "androidx.hilt:hilt-compiler:1.0.0"
implementation "androidx.hilt:hilt-navigation-compose:1.0.0"
我有同样的问题,解决了它在片段和主要活动中添加这个注释@AndroidEntryPointhttps://developer.android.com/training/dependency-injection/hilt-jetpack
你没有在这里提到所以我想你忘了在你的应用程序中添加
@HiltAndroidApp
。
@HiltAndroidApp
class MyOwnApplication : Application() {
}
然后在您的清单文件中添加
android:name=".MyOwnApplication"
在您的应用程序标签中。