The model layer (MVP) should use the Activity reference

Question

How can I make a proper separation between the Model layer and the View layer, when I have an operation in the Model that needs the current activity instance?

For example, I've integrated Linkedin SDK in my Android app (written in MVP). In the auth process I have the following code snippet, when init() method's first argument type is Activity:

public void authWithLinkedin(final IAuth listener, Activity activity) {
    LISessionManager.getInstance(MyApplication.getContext()).init(activity, buildScope(), new AuthListener() {

        @Override
        public void onAuthSuccess() {
            listener.onSuccess();
        }

        @Override
        public void onAuthError(LIAuthError error) {
            listener.onError();
        }

    }, true);
}

If my Model layer should get to know Android framework components, what options do I have left to preserve the MVP architecture clean?

Answer 1

You can use software conventions / principles like

"dependency inversion principle"

"ports and adapters"

Your model layer should not know about Android if you can avoid it is the point.

---

Try something like this:

Model:

private final SocialLoginProvider socialLoginProvider;

public MyModel(SocialLoginProvider socialLoginProvider) {
       this.socialLoginProvider = socialLoginProvider;
}

public void authWithLinkedin(final IAuth listener) {
       socialLoginProvider.init(buildScope(), new SocialLoginProvider.Listener() {

        @Override
        public void onAuthSuccess() {
            listener.onSuccess();
        }

        @Override
        public void onAuthError() {
            listener.onError();
        }

    }, true);
}

Factory:

public MyModel getModel(Context context) {
    LISessionManager li = LISessionManager.getInstance(context);
    SocialLoginProvider provider = new LinkedInSocialLoginProvider(context, li);
    return new MyModel(provider);
}

Interface:

public interface SocialLoginProvider {
     void init(Scope scope, Listener listener);

     interface Listener {
           void onAuthSuccess();
           void onAuthError();
     } 
}

Adapter for SocialLoginProvider:

public class LinkedInSocialLoginProvider implements SocialLoginProvider {

          private final Context context;
          private final LISessionManager linkedInSessionManager;

          public LinkedInSocialLoginProvider(Context context, LISessionManager linkedInSessionManager) {
               this.context = context;
               this.linkedInSessionManager = linkedInSessionManager;
          }

          @Override
          public void init(Scope scope, Listener listener) {
              linkedInSessionManager.init(context, scope, 
                    new AuthListener() {
                      @Override
                      public void onAuthSuccess() {
                         listener.onSuccess();
                      }

                      @Override
                      public void onAuthError(LIAuthError error) {
                         listener.onError();
                      }
                   }, true);
           }

}