Unfortunately, fun facts has stopped

package plarkin.funfacts;

import android.app.Activity;
import android.graphics.Color;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.Button;
import android.widget.RelativeLayout;
import android.widget.TextView;
import android.widget.Toast;

import java.util.Random;

import PLarkin.funfacts.ColorWheel;
import PLarkin.funfacts.FactBook;


public class funfactsactivity extends Activity {
    private FactBook mFactBook = new FactBook();
    private ColorWheel mColorWheel = new ColorWheel();

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_fun_facts);


        final TextView factLabel = (TextView) findViewById(R.id.factTextView);
        final Button showFactButton = (Button) findViewById(R.id.showFactButton);
        final RelativeLayout relativeLayout = (RelativeLayout) findViewById(R.id.relativeLayout);


        View.OnClickListener listener = new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                String fact = mFactBook.getFact();
                factLabel.setText(fact);

                int color = mColorWheel.getColor();
                relativeLayout.setBackgroundColor(color);
                showFactButton.setTextColor(color);
            }
        };
        showFactButton.setOnClickListener(listener);
        String message = "Yay our activity was created!";
        Toast welcomeToast = Toast.makeText(this, message, Toast.LENGTH_LONG);
        welcomeToast.show();
    }
}