注入超型匕首2

Question

Is it possible to inject into supertypes in Dagger 2?

if I have a property like this

@Inject
Wallet<Material>

Would the following provide work ?

@Provides
Wallet<LeatherMaterial> provide()
{
return new Wallet<LeatherMaterial>
}

Actually I should have rephrased the question . It isn't working and I get an error that demands an injection of the exact Wallet

do we have any workarounds ? . does koin provide some functionality like this?

Answer 1

Yes, you need to be explicit. Add the following to your Module, if you already have Wallet<LeatherMaterial> in your dependency graph somewhere:

@Binds abstract Wallet<Material> provide(Wallet<LeatherMaterial> leatherWaller);

Otherwise, go with:

@Provides static Wallet<Material> provide() {
    return new Wallet<LeatherMaterial>(){ /* ... */ };
}

Edit: Revisiting this answer because it occured to me the solutions I've provided wont work due to how generics are treated in Java. Instead, you would need to use:

Wallet<? extends Material> Wallet<? extends Material> in place of Wallet<Material> in my above answers, and do the same wherever it is injected as well.