How to pass class by Interface to AsyncTask?

Issue

I've got a little architectural problem.

I've created an abstract Activity class named BaseActivity.java In this activity I put my business logic login call etc.

This is the basic BaseActivity code:

abstract class BaseActivity extends AppCompatActivity implements BaseActivityInterface {

      protected ApiParameters apiParameters;
      private BaseActivityInterface calledActivity;

      protected void getLoggedUser(BaseActivityInterface calledActivity) {
                this.calledActivity = calledActivity;
                GetLoggedUserTask getLoggedUserTask = new GetLoggedUserTask(this.apiParameters, BaseActivity.this);
                getLoggedUserTask.execute(Utility.LOGIN_URL);
      }

      @Override
      public void updateActivity(JSONObject response) throws JSONException {
          if (response.getInt("status") == HttpURLConnection.HTTP_OK) {
              this.initUserObject(response);
              if (this.calledActivity != null) {
                  this.calledActivity.updateActivity(response);
              }
          } else {
              Toast.makeText(this, response.getString("message"), Toast.LENGTH_LONG).show();
              Intent intent = new Intent(this, LoginActivity.class);
              this.startActivity(intent);
              finish();
          }
     }
}

this is the AsyncTask called GetLoggedUserTask:

public class GetLoggedUserTask extends  AsyncTask<String, BaseActivityInterface, String> {
    private ApiParameters apiParameters;
    private BaseActivityInterface response;

    public GetLoggedUserTask(ApiParameters apiParameters, BaseActivityInterface response) {
        this.apiParameters = apiParameters;
        this.response = response;
    }

this is my child class of BaseActivity called CustomerActivity

public class CustomersActivity extends BaseActivity implements BaseActivityInterface {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        super.getLoggedUser(CustomersActivity.this);
    }


    @Override
    public void updateActivity(JSONObject loginResult) throws JSONException {
        .....
    }
}

and finally my interface BaseActivityInterface

public interface BaseActivityInterface extends Serializable {
    void updateActivity(JSONObject loginResult) throws JSONException;
}

the flow should be: start CustomerActivity.java, pass on super to do a getLoggetUser() and from super BaseActivity, start an AsyncTask. This is the hot point:

when I pass in the asyncTask construct the "BaseActivity.this", and I do debug, the reference of "response" element into GetLoggedUserTask is referred to child CustomerActivity:

Class reference

Where am I doing wrong?

Solution

There is nothing wrong. BaseActivity is an abstract class which means it can not be instantiated. BaseActivity.this will return you the instance of a concrete class that extends BaseActivity, in this case CustomersActivity. You will never see BaseActivity.this as an instance because it's not possible in java, to have instances of abstract classes.

Answered By - Gennadii Saprykin