Kotlin下使用Dagger2出现的坑

当时我想将presenter注入到Activity中,代码如下,make Projiect的时候不通过 百思不得其解

坑1

class MainActivity : AppCompatActivity() ,MainContract.View {


    @Inject
    var mPresenter : MainContract.Presenter ?  = null


    override fun onCreate(savedInstanceState: Bundle?) {
        //******//
        super.onCreate(savedInstanceState)
        DaggerMainActivityComponent.builder().build().inject(this)

        mPresenter?.subscribe()

    }


    @Module
    inner class PresenterModules {

        @Provides
        fun providePresenter(): MainContract.Presenter {
            return MainPresenter(this@MainActivity)
        }
    }
}

@Component(modules = arrayOf(MainActivity.PresenterModules::class))
interface MainActivityComponent {
    fun inject(activity: MainActivity)
}

然后我将kotlin 代码 转成字节码后再转成java代码,发现Presenter是私有的.
而我们都知道,注入的对象不可以是私有的

public final class MainActivity extends AppCompatActivity implements View {
   @Inject
   @Nullable
   private Presenter mPresenter;
-----省略
}

//于是将上述代码改成
 @Inject
    @JvmField
    var mPresenter : MainContract.Presenter ?  = null

//或则
@Inject
lateinit mPresenter : MainContract.Presenter

即可编译成功

坑2

    @Inject
    @JvmField
//    @Named("preneter")// 错误 正确的做法如下 
     @field:[Named("preneter")]
    var mPresenter : MainContract.Presenter ?  = null

    @Module
    inner class PresenterModules {

        @Provides
        @Named("preneter")
        fun providePresenter(): MainContract.Presenter {
            return MainPresenter(this@MainActivity)
        }

        @Provides
        @Named("hello")
        fun provide():String{
            return "hello"
        }
    }