Dagger 2 injecting Android Application Context

Question

I am using Dagger 2 and have it working however I now need access to the Android Application Context.

Its not clear to me how to inject and get access to the context. I have tried to do this as follows:

@Module public class MainActivityModule {         private final Context context;          MainActivityModule(Context context) {         this.context = context;     }      @Provides @Singleton     Context provideContext() {         return context;     } } 

However this results in the following exception:

java.lang.RuntimeException: Unable to create application : java.lang.IllegalStateException: mainActivityModule must be set

If I inspect the Dagger generated code this exception is raised here:

public Graph build() {       if (mainActivityModule == null) {         throw new IllegalStateException("mainActivityModule must be set");     }     return new DaggerGraph(this); } 

I am not sure if this is the correct way to get Context injected - any help will be greatly appreciated.

Answer 1

@Module public class MainActivityModule {         private final Context context;      public MainActivityModule (Context context) {         this.context = context;     }      @Provides //scope is not necessary for parameters stored within the module     public Context context() {         return context;     } }  @Component(modules={MainActivityModule.class}) @Singleton public interface MainActivityComponent {     Context context();      void inject(MainActivity mainActivity); } 

And then

MainActivityComponent mainActivityComponent = DaggerMainActivityComponent.builder()     .mainActivityModule(new MainActivityModule(MainActivity.this))     .build();