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Android Build an Interactive Story App Finishing the User Interface Using a Model in the Presenter

Posted by Zach Rebstock
Zach Rebstock
4,632 Points

toString() not working on exercise practice

I am trying to set the passengersField.setText by calling spaceship.getNumPassengers().toString() inside of the setText.

And I get this error:

./LandingActivity.java:28: error: int cannot be dereferenced passengersField.setText(spaceship.getNumPassengers().toString()); ^ 1 error

public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_landing);

    thrustButton = (Button)findViewById(R.id.thrustButton);
    typeLabel = (TextView)findViewById(R.id.typeTextView);
    passengersField = (EditText)findViewById(R.id.passengersEditText);
    spaceship = new Spaceship("FIREFLY");
    typeLabel.setText(spaceship.getShipType());
    passengersField.setText(spaceship.getNumPassengers().toString());
LandingActivity.java 
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;

public class LandingActivity extends AppCompatActivity {

    public Button thrustButton;
    public TextView typeLabel;
    public EditText passengersField;

    public Spaceship spaceship;

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

        thrustButton = (Button)findViewById(R.id.thrustButton);
        typeLabel = (TextView)findViewById(R.id.typeTextView);
        passengersField = (EditText)findViewById(R.id.passengersEditText);
        spaceship = new Spaceship("FIREFLY");
        typeLabel.setText(spaceship.getShipType());
        passengersField.setText(spaceship.getNumPassengers().toString());

    }
}
Spaceship.java 
public class Spaceship {
    private String shipType;
    private int numPassengers = 0;




    public String getShipType() {
      return shipType;
    }

    public void setShipType(String shipType) {
      this.shipType = shipType;
    }

    public int getNumPassengers() {
      return numPassengers;
    }

    public void setNumPassengers(int numPassengers) {
      this.numPassengers = numPassengers;
    }

    public Spaceship() {
      shipType = "SHUTTLE";
    }

    public Spaceship(String shipType) {
      this.shipType = shipType;
    }
}

1 Answer

Jennifer Nordell
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STAFF
.a{fill-rule:evenodd;}techdegree
Jennifer Nordell
Treehouse Teacher
Jennifer Nordell
.a{fill-rule:evenodd;}techdegree
Jennifer Nordell
Treehouse Teacher

Hi there! The toString is a method on the Integer class which accepts an integer as an argument. Your toString is not accepting anything and is chained onto the end after the getNumPassengers. But the number returned by the the method to get the number of passengers is what should be sent in to toString. If you want to use toString, you could do it like this:

passengersField.setText(Integer.toString(spaceship.getNumPassengers()));

This goes out and gets the number of the passengers and then passes it into the toString method which then returns a string. The string then is passed into the setText.

Alternatively, and a little shorter, you could opt to use Java's type inference:

 passengersField.setText(spaceship.getNumPassengers() + "");

By concatenating an empty string onto the end, Java forces the other part to be a string automatically.

Hope this helps! :sparkles: