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Android Build an Interactive Story App (Retired) Finishing the User Interface Using a Model in the Controller

Posted by Talwinder Singh
Talwinder Singh
1,508 Points

solution to this question

i need answer to this ,didn't actually understood the task

LandingActivity.java 
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;

public class LandingActivity extends Activity {

    public Button mThrustButton;
    public TextView mTypeLabel;
    public EditText mPassengersField;

    public Spaceship mSpaceship;

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

        mThrustButton = (Button)findViewById(R.id.thrustButton);
        mTypeLabel = (TextView)findViewById(R.id.typeTextView);
        mPassengersField = (EditText)findViewById(R.id.passengersEditText);

        // Add your code here!
        mSpaceship = new Spaceship();
        mTypeLabel.setText(mSpaceship.getType());
    }
}
Spaceship.java 
public class Spaceship {
    private String mType;
    private int mNumPassengers = 0;

    public String getType() {
      return mType;
    }

    public void setType(String type) {
      mType = type;
    }

    public int getNumPassengers() {
      return mNumPassengers;
    }

    public void setNumPassengers(int numPassengers) {
      mNumPassengers = numPassengers;
    }

    public Spaceship() {
      mType = "FIREFLY";
    }

    public Spaceship(String type) {
      mType = type;
    }
}

1 Answer

Philip Gales
Philip Gales
15,193 Points
Philip Gales
Philip Gales
15,193 Points

This whole challenge is to teach you to look at the object's class Spaceship.java and to understand/use the methods/constructors.

Step 1: "The LandingActivity interacts with the Spaceship model object we created. Start by setting mSpaceship to a new Spaceship object in the onCreate() method. Use the custom constructor that takes a String parameter, and pass in "FIREFLY" as the parameter."

They want you to use the constructor that takes a parameter when instantiating a Spaceship. Originally, they used the default constructor that takes no parameters, but they want you to use the following constructor from Spaceship.java

    public Spaceship(String type) { //<----You have to type a String inside the method
      mType = type;
    }

More specifically, they want you to type in the string "FIREFLY" as demonstrated below. You will do this in the LandingActivity.java class. Be sure to erase the original mSpaceship = new Spaceship(); from above as this will replace it.

        // Add your code here!
        mSpaceship = new Spaceship("FIREFLY"); //<--------added "FIREFLY"

Step 2: "Now that we have a model object, update the TextView to use the Spaceship's type property. Remember to use the helpful getter method!"

They want you to update the TextView mTypeLabel and set the text to the spaceship's type. You can view the getter method in the Spaceship.java class that gets the type "getType()". 

        // Add your code here!
        mSpaceship = new Spaceship("FIREFLY");
        mTypeLabel.setText(mSpaceship.getType()); //<---- Added code here

As you can tell I used the .setText method to set the text for the mTypeLabel, and then I passed in the spaceship's type using the getter method from the Spaceship class.

Step 3: "Finally, notice that our Spaceship class has a new field to store the number of passengers in the ship. Use the method to get the number of passengers for mSpaceship, and then set the text for mPassengersField to this value. Note: You will need to convert the int value to a String!"

They want you to set the text for the mPassengersField to the number of passengers for mSpaceship. This is very similar to the previous step.

        // Add your code here!
        mSpaceship = new Spaceship("FIREFLY");
        mTypeLabel.setText(mSpaceship.getType());
        mPassengersField.setText(mSpaceship.getNumPassengers() + "");

I added the + "" at the end to convert the int from .getNumPassengers to a string via concatenation. Your final code should look like the following. Notice nothing was done to edit Spaceship.java as we were only given that class so we could see what getter methods were available and use them. 

import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;

public class LandingActivity extends Activity {

    public Button mThrustButton;
    public TextView mTypeLabel;
    public EditText mPassengersField;

    public Spaceship mSpaceship;

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

        mThrustButton = (Button)findViewById(R.id.thrustButton);
        mTypeLabel = (TextView)findViewById(R.id.typeTextView);
        mPassengersField = (EditText)findViewById(R.id.passengersEditText);

        // Add your code here!
        mSpaceship = new Spaceship("FIREFLY");
        mTypeLabel.setText(mSpaceship.getType());
        mPassengersField.setText(mSpaceship.getNumPassengers() + "");
    }
}