如何使用AndroidInjector在模块内部获取MainActivity

随着dagger-android一个现在可以简单地写上如下,并成功注入应用程序的依赖关系:

@Module
public abstract class MainActivityModule {
  @ContributesAndroidInjector
  abstract MainActivity contributesMainActivity();
}

@Singleton
@Component(modules = {
    AndroidSupportInjectionModule.class,
    AndroidInjectionModule.class,
    AppModule.class,
    MainActivityModule.class
})
public interface ApplicationComponent {
  void inject(BaseApplication baseApplication);

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

    ApplicationComponent build();
  }
}

@Module
public abstract class AppModule {}

public class MainActivity extends AppCompatActivity implements 
  HasSupportFragmentInjector {
  @Inject
  DispatchingAndroidInjector dispatchingAndroidInjector;
  @Inject
  Whatever whatever;

  @Override
  protected void onCreate(Bundle savedInstanceState) {
    AndroidInjection.inject(this);
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
  }

  @Override
  public AndroidInjector supportFragmentInjector() {
    return dispatchingAndroidInjector;
  }
}


public class BaseApplication extends Application implements 
  HasActivityInjector {
  @Inject
  DispatchingAndroidInjector dispatchingAndroidInjector;

  @Override
  public AndroidInjector activityInjector() {
    return dispatchingAndroidInjector;
  }

  @Override
  public void onCreate() {
    DaggerApplicationComponent.builder()
            .application(this)
            .build()
            .inject(this);
    super.onCreate();
  }
}

public class Whatever {
   private final FragmentManager fragmentManager;

   @Inject
   Whatever(MainActivity mainActivity) {
    this.fragmentManager = mainActivity.getSupportFragmentManager();
   }
}

一个非常简单的例子.基本上连接所有东西,以便能够通过Whatever注入正确的片段管理器来获取对象.这没关系并且有效.

但是,如果我想在模块中使用主要活动怎么办？假设我想Whatever通过更改构造函数参数实际显式地将依赖项公开给片段管理器:

@Inject
Whatever(FragmentManager fragmentManager) {...}

我现在需要提供这种依赖.怎么去做呢？所以我尝试了以下内容:

@Module
public abstract class MainActivityModule {
  @ContributesAndroidInjector
  abstract MainActivity contributesMainActivity();

  @Provides
  static FragmentManager providesFragmentManager(MainActivity activity) {
     return activity.getSupportFragmentManager();
  }
}

现在匕首抱怨说,它无法找到@Providers的MainActivity.我认为该@ContributesAndroidInjector方法可以提供活动.对于在第一种情况下注入依赖项没有问题,我也有点疑惑,但现在它无法做到.

我也尝试为此建立一个工厂,例如:

public FragmentManagerFactory {
   private final FragmentManager fm;

   @Inject
   FragmentManagerFactory(MainActivity mainActivity){
     this.fm = mainActivity.getSupportFragmentManager();
   }

   public FragmentManager get() {
     return fm;
   }
}

@Module
public abstract class MainActivityModule {
  @ContributesAndroidInjector
  abstract MainActivity contributesMainActivity();

  @Provides
  static FragmentManager providesFragmentManager(FragmentManagerFactory fragmentManagerFactory) {
     return fragmentManagerFactory.get();
  }
}

最终会出现同样的错误.

有没有人设法做到这一点？在它变得非常容易之前,人们只MainActivity需要在一个字段中使用它的实例构建模块并提供它.现在......一切都发生在窗帘后面.

非常感谢一些帮助!

在我的设置我有一个di/在根包sub-di-packages在我的ui/包.在ui/di包中我声明了以下模块和组件:

@dagger.Module
public class MainActivityModule {
   @Provides
   FragmentManager provideFragmentManager(MainActivity mainActivity) {
    return mainActivity.getSupportFragmentManager();
   }
}

MainActivitySubcomponent

@Subcomponent(modules = MainActivityModule.class)
public interface MainActivitySubcomponent  extends AndroidInjector {

    @Subcomponent.Builder
    abstract class Builder extends AndroidInjector.Builder {
    }
}

在di我保留的顶级包装上ApplicationComponent,我有一个额外的module

@Module(subcompOnents= {MainActivitySubcomponent.class })
public abstract class BuildersModule {

   @Binds
   @IntoMap
   @ActivityKey(MainActivity.class)
   abstract AndroidInjector.Factory mainActivityBinder(MainActivitySubcomponent.Builder builder);

}

正如你可以想像BuildersModule,是部分@Component(modules = {的ApplicationComponent.

免责声明: _{^{我是dagger2的新手,我仍然试图找出很多东西.可能有更好的方法来实现您的需求.}}