Dagger multibinding of viewmodels using provides instead of constructor injection

问题

All examples on how to combine ViewModel with dagger2 has been to use constructor injection on the ViewModelFactory. Like this:

private final Map<Class<? extends ViewModel>, Provider<ViewModel>> providers;

@Inject
public ViewModelFactory(Map<Class<? extends ViewModel>, Provider<ViewModel>> providers) {
    this.providers = providers;
}

While the module could look something like this.

@Module
abstract class ViewModelModule {

    @SuppressWarnings("unused")
    @Binds
    @IntoMap
    @ViewModelKey(value = SomeViewModel.class)
    abstract ViewModel bindSomeViewModel(SomeViewModel viewModel);

    @SuppressWarnings("unused")
    @Binds
    abstract ViewModelProvider.Factory 
    bindViewModelFactory(ViewModelFactory viewModelFactory);
}

Now because I like to write reusable code and so I would like to move the factory into another android library module. So I would like to be able to do something like this:

New constructor (just removed @Inject):

private final Map<Class<? extends ViewModel>, Provider<ViewModel>> providers;

public ViewModelFactory(Map<Class<? extends ViewModel>, Provider<ViewModel>> providers) {
    this.providers = providers;
}

And the module:

@Module
abstract class ViewModelModule {

    @SuppressWarnings("unused")
    @Binds
    @IntoMap
    @ViewModelKey(value = SomeViewModel.class)
    abstract ViewModel bindSomeViewModel(SomeViewModel viewModel);

    @SuppressWarnings("unused")
    @Provides
    ViewModelProvider.Factory 
    provideViewModelFactory(Map<Class<? extends ViewModel>, Provider<ViewModel>> providers) {
        // Manually creates the ViewModelFactory.
        return new ViewModelFactory(providers);
    }
}

This gives me the following error

error: com.example.project.ViewModelModule has errors

Question

How do you inject a ViewModelProvider.Factory residing in another module using @Provides which takes the possible view models it creates in the constructor?

Basically, I wan't to use @Provides and call the constructor explicitly instead of letting Dagger do it with constructor injection using @Binds here.

来源：https://stackoverflow.com/questions/56739361/dagger-multibinding-of-viewmodels-using-provides-instead-of-constructor-injectio

标签

java

android

dagger-2

dagger