Android Architecture UI 2

androidMVC2.java

// ----------------------------------------------------------
// VIEW
// ----------------------------------------------------------
// This class represents View layer and also Controller layer
// ----------------------------------------------------------
public interface ActivityListener {
  void showMessage(boolean buttonState, String message);
}

public class MainActivity extends AppCompatActivity implements ActivityListener {
  
  private Button loadButton;
  private TextView console;

  // Inject the Controller with your favorite DI framework.
  @Inject
  MainController mainController;
  
  @Override
  protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    
    // show views
    setContentView(R.layout.some_layout_activity);
    loadButton = (Button) findViewById(R.id.load_button);
    console = (TextView) findViewById(R.id.console_view);
    
    // delegate everything to the controller layer!
    loadButton.setOnClickListener(view -> {
      mainController.loadClick(MainActivity.this);
    });
  }
  
  @Override
  public void showMessage(boolean buttonState, String message) {
    runOnUiThread(() -> {
      loadButton.setEnabled(buttonState);
      console.setText(message);
    });
  }
  
}

// ----------------------------------------------------------
// CONTROLLER
// ----------------------------------------------------------
public class MainController {
  
  private final CloudApi cloudApi;
  
  public MainController(CloudApi cloudApi) {
    this.cloudApi = cloudApi;
  }
  
  public void clickLoad(ActivityListener listener) {
    doOnBackgroundThread(() -> {
      cloudApi.downloadSomething(listener);
    });
  }
  
}

// ----------------------------------------------------------
// MODEL
// ----------------------------------------------------------
// Classes that represents the Model layer
// ----------------------------------------------------------
public class CloudApi {
  
  public void downloadSomething(ActivityListener listener) {
    listener.showMessage(false, "DOWNLOADING");
    try {
      Thread.sleep(5 * 1000); // simulate downloading something
    } catch (InterruptedException e) {
      listener.showMessage(true, e.getMessage());
    }
    listener.showMessage(true, "DOWNLOADED, CLICK AGAIN!"));
  }
  
}