ext.kotlin_version = "1.5.0"//kotlin版本
ext.hilt_version = '2.35'//hilt版本
repositories {
    google()
    mavenCentral()
}
dependencies {
    classpath "com.android.tools.build:gradle:4.2.1"
    classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
    classpath 'com.google.dagger:hilt-android-gradle-plugin:2.35'
}
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implementation "com.google.dagger:hilt-android:$hilt_version"
kapt "com.google.dagger:hilt-android-compiler:$hilt_version"
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id 'kotlin-kapt'
id 'kotlin-android-extensions'
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@HiltAndroidApp
class App: Application() {
    override fun onCreate() {
        super.onCreate()
    }
}
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@AndroidEntryPoint
public class ExampleActivity extends AppCompatActivity {
  @Inject
  AnalyticsAdapter analytics;
  ...
}
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@HiltAndroidApp
class App: Application() {
}
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class Car @Inject constructor() {
    fun drive(name: String) {
        println("老司机$name 在线开车")
    }
}
//Car的构造使用@Inject表示Car对象是一个可被注入的对象
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@AndroidEntryPoint
class MainActivity : AppCompatActivity() {
    @Inject
    lateinit var car: Car//Car对象使用@Inject注解，会自动被实例化，这里必须使用lateinit延迟初始化才会有效
    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)
        car.drive("mage")
    }
}
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class Car @Inject constructor(val driver: Driver) {//Car的构造函数中增加了Driver司机对象的实现
    fun drive() {
        println("老司机${driver.name} 在线开车")
    }
}
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interface Driver {
    val name :String
}
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class DriverImpl @Inject constructor() : Driver {//因为DriverImpl需要被注入到Car的构造中，所以DriverImpl本身一个是被注入着，他的构造中也需要使用@Inject注解
    override val name: String
        get() = "mage"
}
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@Module//必须配置的注解，表示这个对象是Module的配置规则
@InstallIn(ActivityComponent::class)//表示这个module中的配置是用来注入到Activity中的
abstract class DriverModule {
    @Binds
    abstract fun bindDriver(driver: DriverImpl): Driver//形参中的DriverImple表示真实要注入Car构造方法中的Driver实现，返回值Driver表示DriverImple所实现的抽象接口
}
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@AndroidEntryPoint
class MainActivity : AppCompatActivity() {
    @Inject
    lateinit var car: Car//这里必须使用lateinit延迟初始化才会有效
    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)
        car.drive()
    }
}
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@Module
@InstallIn(ActivityComponent::class)
object OkhttpModule {
    @Provides
    fun provideOkhttpClient(
        // Potential dependencies of this type
    ): OkHttpClient {
        return OkHttpClient()
    }
    @Provides
    fun providdeRequest():Request{
        return Request.Builder()
            .get()
            .url("https://developer.android.google.cn/training/dependency-injection/hilt-android")
            .build()
    }
}
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@AndroidEntryPoint
class MainActivity : AppCompatActivity() {
    @Inject
    lateinit var client: OkHttpClient
    @Inject
    lateinit var request: Request
    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)
        btn.setOnClickListener {
            client.newCall(request).enqueue(object :Callback{
                override fun onFailure(call: Call, e: IOException) {
                    println("请求失败")
                }
                override fun onResponse(call: Call, response: Response) {
                    println("请求成功")
                }
            })
        }
    }
}
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@Inject
lateinit var truck: Car
@Inject
lateinit var taxi: Car
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interface Car {
    fun drive(name:String)
}
class TruckCar @Inject  constructor():Car{
    override fun drive(name: String) {
        println("$name 卡车老司机开车，呜呜")
    }
}
class TaxiCar @Inject  constructor():Car{
    override fun drive(name: String) {
        println("$name 出租车老司机开车，呜呜")
    }
}
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@Qualifier
@Retention(AnnotationRetention.BINARY)
annotation class Truck//卡车类注入标记
@Qualifier
@Retention(AnnotationRetention.BINARY)
annotation class Taxi//出租车类注入标记
@Module
@InstallIn(ActivityComponent::class)
class CarModule {
    @Truck//卡车类生成规则加上这个注解，注入的时候也是用该注解编译器就可以知道我们真实想注入的类型是TruckCar
    @Provides
    fun bindTruckCar(truckCar: TruckCar): Car {
        return TruckCar()
    }
    @Taxi//出租车类生成规则加上这个注解，注入的时候也是用该注解编译器就可以知道我们真实想注入的类型是TaxiCar
    @Provides
    fun bindTaxtCar(taxiCar: TaxiCar): Car {
        return TaxiCar()
    }
}
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class BaseInfo @Inject constructor(@ActivityContext private val context: Context) {
    fun printPackageName(){
        println("应用包名 ${context.packageName}")
    }
}
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@AndroidEntryPoint
class MainActivity : AppCompatActivity() {
    @Inject
    lateinit var baseInfo: BaseInfo
    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)
        btn.setOnClickListener {
            baseInfo.printPackageName()
        }
    }
}
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