Inject dependencies to Presenters into the Views when instantiating the Presenters, as this reduces coupling issues and null checks.

Description

Injecting presenters using Dagger reduces null checks and setPresenter() methods. Whenever an activity is used, Dagger couples the view with the Presenter. Which ultimately results into clearer code.

Example

We created a simple MVP login Application.

The ViewUserModule provides the ViewUserComponent with the ViewUserPresenter.

	@Module
	public class ViewUserModule {

	private ViewUsersView viewUsersView;

	public ViewUserModule(ViewUsersView viewUsersView) {
	this.viewUsersView = viewUsersView;
	}

	@ViewUserScope
	@Provides
	ViewUsersView provideViewUsersView() {
	return viewUsersView;
	}

	@ViewUserScope
	@Provides
	ViewUserPresenter provideViewUserPresenter(ViewUserInteractor viewUserInteractor) {
	return new ViewUserPresenter(viewUsersView, viewUserInteractor);
	}
	}

view raw ViewUserModule.java hosted with ❤ by GitHub

This ViewUserPresenter gets initialized with the viewUsersView. Which is added when the module is instantiated.

	@Override
	protected void setupComponent() {
	MVPLoginApplication.get(this)
	.getAuthComponent()
	.plus(new ViewUserModule(this))
	.inject(this);
	}

view raw ViewUsersActivity.java hosted with ❤ by GitHub

Which happens in the viewUsersActivity. So whenever a new Presenter is created, the Presenter always has a relationship with a view. So this is never null.

Check out the Github page to view the complete repository.

mvp

Description

Example