Dagger 2 singleton registry-CodePudding

Hi in our project we use micronaut, and we have a code that looks like this:

beanContext.registerSingleton(foo::class.java, myFooObject)

Now we are trying to work with dagger2, any idea how can I achieve something similar?

CodePudding user response：

In your dagger module you need to declare the provide method with the @Singletone annotation, for example:

@Module
class AppModule {

    @Provides
    @Singleton
    fun provideMyFoo(): MyFoo {
        return MyFoo()
    }
}

CodePudding user response：

I found a way to do bind a singleton outside of the component. by using @BindsInstance

Here is an example of code where MyFoo is the class I want to inject outside of my comonent :

import dagger.BindsInstance
import dagger.Component
import javax.inject.Singleton

@Singleton
@Component(modules = [Car::class])
interface ComponentCar {

    fun getCar(): Car

    @Component.Builder
    interface Builder {
        @BindsInstance
        fun setMyFoo(myFoo: MyFoo): Builder
        fun build(): ComponentCar
    }
}

Then later in the init code I do something like this:

val component = DaggerComponentCar.builder().setMyFoo(mySingleMyFoo).build()