Hilt-依赖注入框架上手指南

@Singletion
class TestCompenent @Inject constructor()

implementation 'com.google.dagger:hilt-android:2.28-alpha'
kapt 'com.google.dagger:hilt-android-compiler:2.28-alpha'

classpath 'com.google.dagger:hilt-android-gradle-plugin:2.28-alpha'

apply plugin: 'dagger.hilt.android.plugin'

class NetDataSource{
    fun test(){
        println("我只是一个测试方法")   
    }
}

class MainActivity : AppCompatActivity() {
    lateinit var netDataSource: NetDataSource
    override fun onCreate(savedInstanceState: Bundle?) {
        ...
        netDataSource = NetDataSource()
    }
}

class NetDataSource @Inject constructor(){
    fun test(){
        println("我只是一个测试方法")
    }
}

@AndroidEntryPoint
class MainActivity : AppCompatActivity() {
    @Inject
    lateinit var netDataSource: NetDataSource
    override fun onCreate(savedInstanceState: Bundle?) {
       	...
        netDataSource.test()
    }
}

@HiltAndroidApp
class KtxApplication : Application()

@InstallIn(ApplicationComponent::class)
@Module
object TestModule {
	
  //每次都是新的实例
  @Provides
  fun bindBook():Book{
    	return Book()
  }
  
  //全局复用同一个实例
  @Provides
  @Singleton
  fun bindBook():BookSingle{
    	return Book()
  }
}

@Entity(tableName = "book")
class Book(val name: String) {
	 @PrimaryKey(autoGenerate = true)
    var id: Long = 0
}

@Dao
interface BookDao {
    @Insert
    suspend fun insertAll(vararg books: Book)

    @Query("SELECT COUNT(*) FROM book")
    suspend fun queryBookAll(): Int
}

@Database(entities = [Book::class], version = 1)
abstract class AppDataBase : RoomDatabase() {
    abstract fun bookDao(): BookDao
}

object RoomSingle {
    lateinit var context: Context
    val roomDatabase by lazy {
        Room.databaseBuilder(
            context,
            AppDataBase::class.java,
            "logging.db"
        ).build()
    }
}

class MainActivity : AppCompatActivity() {
    val bookDao by lazy {
        RoomSingle.roomDatabase.bookDao()
    }
}

@InstallIn(ApplicationComponent::class)
@Module
object BookModule {
 	@Provides
    @Singleton
    fun provideDatabase(@ApplicationContext appContext: Context): AppDatabase {
        return Room.databaseBuilder(
            appContext,
            AppDatabase::class.java,
            "book.db"
        ).build()
    }
  
    @Provides
    fun provideBookDao(database: AppDatabase): BookDao {
        return database.bookDao()
    }
}

@AndroidEntryPoint
class MainActivity : AppCompatActivity() {
    @Inject
    lateinit var bookDao: BookDao
}

 interface IBook {
    suspend fun saveBook(name: String)

    suspend fun getBookAllSum(): Int
}

class BookImpl @Inject constructor() : IBook {
    @Inject
    lateinit var dao: BookDao
    override suspend fun saveBook(name: String) {
        //这里可能会有一些自己的处理...
        dao.insertAll(Book(name))
    }
  
   override suspend fun getBookAllSum(): Int {
        return dao.queryBookAll()
    }
} 

@InstallIn(ApplicationComponent::class)
@Module
abstract class BookModel {
 @Binds
    abstract fun getIBook(impl: BookImpl): IBook
   } 

@AndroidEntryPoint
class MainActivity : AppCompatActivity() {
    @Inject
    lateinit var iBook: IBook

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)
        btnSave.setOnClickListener {
            lifecycleScope.launch(Dispatchers.IO) {
                iBook.saveBook("Android艺术")
                val sum = iBook.getBookAllSum()
                Log.e("petterp", "当前长度-----$sum")
            }
        }
    }
}

 class BookConditionImpl @Inject constructor() : IBook {
    @Inject
    lateinit var dao: BookDao
    override suspend fun saveBook(name: String) {
        if (name == "Android艺术") {
            dao.insertAll(Book("Petterp"))
        }
    }

    override suspend fun getBookAllSum(): Int {
        return dao.queryBookAll()
    }

}

 @InstallIn(ApplicationComponent::class)
@Module
abstract class BookModel {
    @Binds
    @Singleton
    abstract fun getIBook(impl: BookImpl): IBook
}

@InstallIn(ActivityComponent::class)
@Module
abstract class BookConditionModel {
    @Binds
    @ActivityScoped
    abstract fun getConditionIBook(impl: BookConditionImpl): IBook
}

 @Qualifier
annotation class BookModelSingle

@Qualifier
annotation class BookModelCondition

@InstallIn(ApplicationComponent::class)
@Module
abstract class BookModel {
    @BookModelSingle
    @Binds
    @Singleton
    abstract fun getIBook(impl: BookImpl): IBook
}

//其模块范围为Activity
@InstallIn(ActivityComponent::class)
@Module
abstract class BookConditionModel {
    @Binds
    @ActivityScoped
    @BookModelCondition
    abstract fun getConditionIBook(impl: BookConditionImpl): IBook
}

 @AndroidEntryPoint
class MainActivity : AppCompatActivity() {
    @BookModelCondition
    @Inject
    lateinit var iBookCondition: IBook

    @BookModelSingle
    @Inject
    lateinit var iBook: IBook
   
}

    implementation 'androidx.hilt:hilt-lifecycle-viewmodel:1.0.0-alpha02'
    kapt 'androidx.hilt:hilt-compiler:1.0.0-alpha02'
		
		
		//viewModel的数据恢复，可以不导入，这里只是为了演示
    implementation "androidx.lifecycle:lifecycle-viewmodel-savedstate:2.2.0"
		//便于 使用ViewModel-ktx扩展
    implementation 'androidx.activity:activity:1.1.0'
    implementation 'androidx.fragment:fragment-ktx:1.2.5'

@AndroidEntryPoint
class MainActivity : AppCompatActivity() {

    private val viewModel by viewModels<TestViewModel>()

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

class TestViewModel @ViewModelInject constructor(
    private val repository: TestRepository,
    @Assisted val savedState: SavedStateHandle
) : ViewModel() {
    fun test() {
        repository.test()
    }
}

@ActivityScoped
class TestRepository @Inject constructor() {
    fun test() {
        Log.e("petterp", "一个测试方法")
    }
}

public class TestViewModel extends ViewModel {
    @ViewModelInject
    public TestViewModel() {

    }
    public void test(){
        Log.e("petterp","我是测试方法");
    }
}