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Android Testing in Android Unit Testing Viewing the Presenter

Posted by Henry Antonio Ambicho Trujillo
Henry Antonio Ambicho Trujillo
Courses Plus Student 686 Points

I don't understan why do you ask me the constructor, because , I have create this.

My MainActivityPresenter have a constructor, but nevertheless the error persiste

MainActivity.java 
public class MainActivity extends AppCompatActivity implements MainActivityView{
    TextView counter;
    Button button;

    MainActivityPresenter presenter;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        presenter = new MainActivityPresenter(this);

        counter = (TextView) findViewById(R.id.textView);
        button = (Button) findViewById(R.id.button);
        button.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                int count = Integer.parseInt(counter.getText().toString());
                presenter.incrementValue(count);
            }
        });
    }

      @Override
    public void incrementNumber(int valor) {
        counter.setText(Integer.toString(valor + 1));
    }

}
MainActivityView.java 
public interface MainActivityView {
  public void incrementNumber(int valor); 
}
MainActivityPresenter.java 
public class MainActivityPresenter {
    MainActivity view;

    public MainActivityPresenter(MainActivity view) {
        this.view = view;
    }

    public void incrementValue(int value) {
        view.incrementNumber(value);
    }
}

1 Answer

Rares Conea
PLUS
Rares Conea
Courses Plus Student 15,000 Points
Rares Conea
Rares Conea
Courses Plus Student 15,000 Points

Hi,

You can not call incrementValue() on an reference to an object of MainActivity type because the compiler does not know that MainActivity implements MainActivityView and that it also has that method. In your Presenter the field where you want to store the value received in the constructor should be of type MainActivityView, the same type should be also the value received.

MainActivityView view;

public MainActivityPresenter(MainActivityView view) {
    this.view = view;
}