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22,341 PointsWhat is missing in the presenter ?
Here's a simple counter app consisting of only a TextView and a Button. When the Button is pressed the counter (TextView) increases by one. Refactor this to now use a View and Presenter.
Bummer! Don't forget to create a new constructor in the presenter!
What is missing in the presenter ? I already have a constructor in there.
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.buttonClicked(Integer.toString(count + 1));
}
});
}
@Override
public void changeTextViewText(String text) {
counter.setText(text);
} //changeTextViewText()
}
public interface MainActivityView {
void changeTextViewText(String text);
}
public class MainActivityPresenter {
MainActivityView view;
public MainActivityPresenter(MainActivity view) {
this.view = view;
} // MainActivityPresenter()
public void buttonClicked(String text) {
view.changeTextViewText(text);
} // editTextUpdated()
}
3 Answers
Ben Deitch
Treehouse TeacherFixed; it should work now!
durul
62,690 PointsHello, I tried to above code blocks, but I have taken same error message "Don't forget to create a new constructor in the presenter!"
Guilherme Cunha
1,648 PointsI'm experiencing the some problem, how did you solve it? Why u don't put the sum function in presenter?
Trainer Workout
22,341 PointsI moved the calculation to the presenter, but it still does not work.
Ben Deitch
Treehouse TeacherHey Guilherme! I'm not entirely sure what's going on here, could you post your code to help me figure it out?
Trainer Workout
22,341 PointsI tested the code above with the the second constructor. It works now :)
Trainer Workout
22,341 PointsTrainer Workout
22,341 PointsI changed my constructor in MainActivityPresenter to this but still no luck