我是Dagger 2的新手。我有2个活动，我想使用注入的ViewModel。这是我的 ViewModuleFactory ：
@Singleton
public class ProductViewModelFactory implements ViewModelProvider.Factory {
private final Map<Class<? extends ViewModel>, Provider<ViewModel>> creators;
@Inject
public ProductViewModelFactory(Map<Class<? extends ViewModel>, Provider<ViewModel>> creators) {
this.creators = creators;
}
@SuppressWarnings("unchecked")
@Override
public <T extends ViewModel> T create(Class<T> modelClass) {
Provider<? extends ViewModel> creator = creators.get(modelClass);
if (creator == null) {
for (Map.Entry<Class<? extends ViewModel>, Provider<ViewModel>> entry : creators.entrySet()) {
if (modelClass.isAssignableFrom(entry.getKey())) {
creator = entry.getValue();
break;
}
}
}
if (creator == null) {
throw new IllegalArgumentException("unknown viewmodel class " + modelClass);
}
try {
return (T) creator.get();
} catch (Exception e) {
throw new RuntimeException(e);
}
}
}
我的 ViewModelModule ：
@Module
abstract class ViewModelModule {
@Binds
@IntoMap
@ViewModelKey(ProductListViewModel.class)
abstract ViewModel bindProductListViewModel(ProductListViewModel listViewModel);
@Binds
@IntoMap
@ViewModelKey(ProductDetailsViewModel.class)
abstract ViewModel bindProductDetailsViewModel(ProductDetailsViewModel detailsViewModel);
@Binds
abstract ViewModelProvider.Factory bindViewModelFactory(ProductViewModelFactory factory);
}
我的 ViewModelKey 用于映射：
@Documented
@Target({ElementType.METHOD})
@Retention(RetentionPolicy.RUNTIME)
@MapKey
@interface ViewModelKey {
Class<? extends ViewModel> value();
}
我的 ActivityModule ：
@Module
public abstract class ActivityModule {
abstract ProductListActivity contributeProductListActivity();
abstract ProductDetailsActivity contributeProductDetailsActivity();
}
我的 AppModule ：
@Module
class AppModule {
@Provides
@Singleton
RedMartProductService provideRedMartProductService() {
........
}
@Provides
@Singleton
ProductListRepository provideProductListRepository(ProductListRepository repository) {
return repository;
}
@Provides
@Singleton
ProductDetailsRepository provideProductDetailsRepository(ProductDetailsRepository repository) {
return repository;
}
}
我的 AppComponent ：
@Singleton
@Component(modules = {AndroidInjectionModule.class, ActivityModule.class, AppModule.class})
public interface AppComponent {
@Component.Builder
interface Builder {
@BindsInstance
Builder application(Application application);
AppComponent build();
}
void inject(MartApplication martApp);
}
我的申请：
public class MartApplication extends Application implements HasActivityInjector {
@Inject
DispatchingAndroidInjector<Activity> dispatchingAndroidInjector;
@Override
public void onCreate() {
super.onCreate();
}
@Override
public DispatchingAndroidInjector<Activity> activityInjector() {
return dispatchingAndroidInjector;
}
}
在活动：
中@Inject
ViewModelProvider.Factory viewModelFactory;
.......
AndroidInjection.inject(activity); // Throwing exception
ListViewModel = ViewModelProviders.of(this, viewModelFactory).get(ProductListViewModel.class);
注入时会抛出异常：
java.lang.IllegalArgumentException: No injector factory bound for Class<com.mymart.ui.ProductListActivity>
有人可以帮我识别代码中的问题吗？
............................................... ........................
修改：我根据@azizbekian尝试使用ContributesAndroidInjector，但是在构建时出现以下错误：
error: [dagger.android.AndroidInjector.inject(T)] Found a dependency cycle:
com.mymart.repository.ProductListRepository is injected at
com.mymart.di.AppModule.provideProductListRepository(repository)
com.mymart.repository.ProductListRepository is injected at
com.mymart.viewmodel.ProductListViewModel.<init>(productListRepository)
com.mymart.viewmodel.ProductListViewModel is injected at
com.mymart.di.ViewModelModule.bindProductListViewModel(listViewModel)
java.util.Map<java.lang.Class<? extends android.arch.lifecycle.ViewModel>,javax.inject.Provider<android.arch.lifecycle.ViewModel>> is injected at
com.mymart.viewmodel.ProductViewModelFactory.<init>(creators)
com.mymart.viewmodel.ProductViewModelFactory is injected at
com.mymart.di.ViewModelModule.bindViewModelFactory(factory)
android.arch.lifecycle.ViewModelProvider.Factory is injected at
com.mymart.ui.ProductListActivity.viewModelFactory
com.mymart.ui.ProductListActivity is injected at
dagger.android.AndroidInjector.inject(arg0)
编辑2 在所有变化之后，我再次面临异常：
java.lang.RuntimeException: Unable to create application com.kaushik.myredmart.MartApplication: java.lang.IllegalStateException: com.kaushik.myredmart.di.AppModule must be set
at android.app.ActivityThread.handleBindApplication(ActivityThread.java:4710)
at android.app.ActivityThread.-wrap1(ActivityThread.java)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1405)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:148)
at android.app.ActivityThread.main(ActivityThread.java:5417)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:726)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:616)
Caused by: java.lang.IllegalStateException: com.kaushik.myredmart.di.AppModule must be set
at com.kaushik.myredmart.di.DaggerAppComponent$Builder.build(DaggerAppComponent.java:180)
at com.kaushik.myredmart.di.AppInjector.init(AppInjector.java:30)
at com.kaushik.myredmart.MartApplication.onCreate(MartApplication.java:28)
at android.app.Instrumentation.callApplicationOnCreate(Instrumentation.java:1013)
at android.app.ActivityThread.handleBindApplication(ActivityThread.java:4707)
at android.app.ActivityThread.-wrap1(ActivityThread.java)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1405)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:148)
at android.app.ActivityThread.main(ActivityThread.java:5417)
at java.lang.reflect.Method.invoke(Native Method)
答案 0 :(得分：53)
我相信你忘记了@ContributesAndroidInjector注释：
@Module
public abstract class ActivityModule {
@ContributesAndroidInjector
abstract ProductListActivity contributeProductListActivity();
@ContributesAndroidInjector
abstract ProductDetailsActivity contributeProductDetailsActivity();
}
并在ViewModelModule中加入AppModule：
@Module(includes = ViewModelModule.class)
class AppModule {
...
}
请参阅您编写的以下代码：
@Provides
@Singleton
ProductListRepository provideProductListRepository(ProductListRepository repository) {
return repository;
}
您期望发生什么？你告诉匕首“嘿，匕首，每当我要求你提供ProductListRepository然后使用ProductListRepository”创建（返回）该对象时。那不会有用。
你最想要的是“嘿，匕首，每当我要求你提供ProductListRepository的实现，然后使用ProductListRepositoryImpl 创建（返回）该对象时：
@Provides
@Singleton
ProductListRepository provideProductListRepository(ProductListRepositoryImpl repository) {
return repository;
}
可以用以下代替：
@Binds
@Singleton
abstract ProductListRepository provideProductListRepository(ProductListRepositoryImpl repository);
答案 1 :(得分：0)
对于这个错误：“Dagger：IllegalArgumentException：没有为类绑定的注入器工厂”
如果您将导航组件与单个活动一起使用，您会看到此错误。
<块引用>你应该怎么做？
请检查您的 @Module 抽象类 FragmentProvider { ... } 因为您需要在其中添加您的 Fragment 作为 Contribute。
@Module
abstract class FragmentProvider {
@ContributesAndroidInjector // <-- Do not forget this line.
abstract fun contributeYourNewFragment(): YourNewFragment
}
答案 2 :(得分：-6)
使用@contrubutesAndroidInjector需要额外的annotationProcessor。
将此行添加到您的gradle构建文件中：
annotationProcessor 'com.google.dagger:dagger-android-processor:2.11'