Question

我目前正在开发一个android应用，并使用匕首进行依赖注入。尝试将依赖项注入片段时遇到麻烦。我正在使用以下模块中提供的蓝牙服务。

@Module
public abstract class BluetoothModule {

    @Provides
    @Singleton
    @NonNull
    static RxBleClient provideRxBleClient(Context context) {
        RxBleClient client = RxBleClient.create(context);

        RxBleClient.setLogLevel(RxBleLog.VERBOSE);
        return client;
    }

    @Binds
    @Reusable
    @Production
    abstract IBluetoothService provideBlueToothService(BluetoothService bluetoothService);

    @Binds
    @Reusable
    @Test
    abstract IBluetoothService provideMockBlueToothService(MockBluetoothService bluetoothService);

}

由于我使用的是MVP模式，因此我想将此服务注入Presenter（构造函数注入），然后将Presenter注入片段（使用字段注入）。如果我将主持人注入到主要活动中，一切都会很好。

@Module
public abstract class MainActivityModule {

    @Provides
    @ActivityScoped
    static MainActivityPresenter provideMainActivityPresenter(
            SchedulerProvider schedulerProvider,
            @Test IBluetoothService bluetoothService) {

        return new MainActivityPresenter(schedulerProvider, bluetoothService);
    }


}

但是，当我将BluetoothService int FragmentPresenter注入时

@Module
public abstract class MapFragmentModule {

    @Provides
    @Reusable
    static MapPresenter provideMapPresenter(SchedulerProvider provider,
                                            @Test IBluetoothService bluetoothService) {
        return new MapPresenter(provider,bluetoothService);
    }
}

我有以下错误

error: [Dagger/MissingBinding] [dagger.android.AndroidInjector.inject(T)] com.wavy.services.bluetooth.IBluetoothService cannot be provided without an @Provides-annotated method.
public interface ApplicationComponent extends AndroidInjector<DaggerApplication>{
       ^
      com.wavy.services.bluetooth.IBluetoothService is injected at
          com.wavy.ui.map.MapPresenter.<init>(…, bluetoothService)
      com.wavy.ui.map.MapPresenter is injected at
          com.wavy.ui.map.MapFragment.mapPresenter
      com.wavy.ui.map.MapFragment is injected at
          com.wavy.ui.MainActivity.mapFragment
      com.wavy.ui.MainActivity is injected at
          dagger.android.AndroidInjector.inject(T)
  component path: com.wavy.config.dagger.components.ApplicationComponent → com.wavy.config.dagger.builders.ActivityBuilder_BindMainActivity.MainActivitySubcomponent

所以我在github上发现了与我类似的问题 Issue Link

解决方案是不要在Fragment构造函数中使用@Inject批注，所以我做到了，之后又遇到另一个错误

error: [Dagger/MissingBinding] [dagger.android.AndroidInjector.inject(T)] com.wavy.ui.map.MapFragment cannot be provided without an @Inject constructor or an @Provides-annotated method. This type supports members injection but cannot be implicitly provided.
public interface ApplicationComponent extends AndroidInjector<DaggerApplication>{
       ^
  A binding with matching key exists in component: com.wavy.config.dagger.builders.FragmentBuilder_BindMapFragment.MapFragmentSubcomponent
      com.wavy.ui.map.MapFragment is injected at
          com.wavy.ui.MainActivity.mapFragment
      com.wavy.ui.MainActivity is injected at
          dagger.android.AndroidInjector.inject(T)
  component path: com.wavy.config.dagger.components.ApplicationComponent → com.wavy.config.dagger.builders.ActivityBuilder_BindMainActivity.MainActivitySubcomponent

这就是我提供片段的方式

  @ContributesAndroidInjector(modules = {MapFragmentModule.class})
  abstract MapFragment bindMapFragment();

蓝牙服务

public class BluetoothService implements IBluetoothService {
        private final RxBleClient rxBleClient;

        @Inject
        public BluetoothService(RxBleClient rxBleClient) {
            this.rxBleClient = rxBleClient;
        }

//code omitted for clarity
}

地图片段

public class MapFragment extends BaseFragment {

    @Inject
    MapPresenter mapPresenter;

    @Inject
    public MapFragment() {
        // Required empty public constructor
    }
//code omitted for clarty
}

地图演示者

public class MapPresenter extends BasePresenter<MapFragment> {
    private final IBluetoothService bluetoothService;

    @Inject
    public MapPresenter(SchedulerProvider schedulerProvider,
                        IBluetoothService bluetoothService) {
        super(schedulerProvider);
        this.bluetoothService = bluetoothService;
    }
    //code ommited for clarity
}

ActivityBuilder

@Module
public abstract class ActivityBuilder {

    @ActivityScoped
    @ContributesAndroidInjector(modules = {MainActivityModule.class, FragmentBuilder.class})
    abstract MainActivity bindMainActivity();

}

AppComponent

@Singleton
@Component(modules = {
        AndroidSupportInjectionModule.class,
        ApplicationModule.class,
        ActivityBuilder.class,
        BluetoothModule.class,
        RetrofitRestClientModule.class,
        RxModule.class,
        ApiModule.class,
        RoomDatabaseModule.class
})
public interface ApplicationComponent extends AndroidInjector<DaggerApplication>{

    void inject(WavyApplication application);

    @Override
    void inject(DaggerApplication instance);

    @Component.Builder
    interface Builder{
        @BindsInstance
        Builder application(Application application);
        ApplicationComponent build();

    }
}

非常感谢您提出解决此问题的想法

Answer 1

您可能忘记了将片段模块包括在活动子组件中。你应该有这样的东西：

abstract class MapFragmentBuilderModule {

    @ContributesAndroidInjector(modules = {MapFragmentModule.class})
    abstract MapFragment bindMapFragment();

}

，然后在您的活动模块中：

@ActivityScoped
@ContributesAndroidInjector(modules = [MainModule::class, MapFragmentBuilderModule::class])
internal abstract fun mainActivity(): MainActivity

将依赖项注入匕首片段的问题

1 个答案: