Unfortunately, Crystall Ball has stopped

private CrystallBall myCrystallBall = new CrystallBall();
@Override
protected void onCreate(Bundle savedInstanceState) {

    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    //Declare our View variables 
    final TextView answerLabel = (TextView)findViewById(R.id.textView1);
    Button getAnswerButton = (Button)findViewById(R.id.btnEnligth);

    getAnswerButton.setOnClickListener(new View.OnClickListener() {

        @Override
        public void onClick(View v) {
            // TODO Auto-generated method stub


    answerLabel.setText(myCrystallBall.getAnAnswer());          }
    });
}


@Override
public boolean onCreateOptionsMenu(Menu menu) {
    // Inflate the menu; this adds items to the action bar if it is present.
    getMenuInflater().inflate(R.menu.main, menu);
    return true;
}

private String []answer = {"It is certain",
        "You are programming like a turtle",
        "I hope this get faster 'cause 'm getting bored",
        "Yes, this is android",
"I like the way you look at me"};

public String getAnAnswer(){


    Random randomGenerator = new Random();
    int randomNumber = randomGenerator.nextInt(answer.length);
    return answer[randomNumber];
}

<ImageView
    android:id="@+id/imageView1"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:layout_alignRight="@+id/button1"
    android:scaleType="fitCenter"
    android:src="@drawable/ball01" />

<Button
    android:id="@+id/button1"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:layout_alignBottom="@+id/imageView1"
    android:layout_centerHorizontal="true"
    android:text="Enlighten me!" />

<TextView
    android:id="@+id/textView1"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_above="@+id/button1"
    android:layout_alignLeft="@+id/imageView1"
    android:layout_marginBottom="149dp"
    android:text="You&apos;ll be so proud of your first application"
    android:textSize="32sp"
    android:typeface="serif" />