Emulator was working fine / Now showing Black Screen after adding the Shaking xml

package com.example.crystallball;

import android.app.Activity;
import android.graphics.drawable.AnimationDrawable;
import android.hardware.Sensor;
import android.hardware.SensorManager;
import android.media.MediaPlayer;
import android.media.MediaPlayer.OnCompletionListener;
import android.os.Bundle;
import android.view.Menu;
import android.view.animation.AlphaAnimation;
import android.widget.ImageView;
import android.widget.TextView;
import android.widget.Toast;

    import com.example.crystallball.ShakeDetector.OnShakeListener;

    public class MainActivity extends Activity {
    private CrystallBallGenerator mcrystall = new CrystallBallGenerator() ;
    private TextView mAnswerlabel;
    private ImageView mCrystallballimage;
    private SensorManager mSensorManager;
    private Sensor mAccelerometer;
    private ShakeDetector mShakeDetector;





    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        mAnswerlabel = (TextView) findViewById(R.id.textView1);
        mCrystallballimage = ( ImageView) findViewById (R.id.imageView1);
        mSensorManager = (SensorManager) getSystemService (SENSOR_SERVICE);
        mAccelerometer = mSensorManager.getDefaultSensor(Sensor.TYPE_ACCELEROMETER);
        mShakeDetector = new ShakeDetector ( new OnShakeListener() {

        @Override
        public void onShake() {
            answerHandle();
        }
    });


      Toast.makeText(this, "welcome",Toast.LENGTH_LONG).show();
    }







    private void animateCrystallBall() {

        mCrystallballimage.setImageResource(R.drawable.ball_animation);
        AnimationDrawable ballAnimation = ( AnimationDrawable ) mCrystallballimage.getDrawable();
        if (ballAnimation.isRunning()){
            ballAnimation.stop();

        }
        ballAnimation.start();
    }

    private void animateAnswer(){
    AlphaAnimation fadeInAnimation = new AlphaAnimation(0 ,1);
    fadeInAnimation.setDuration(1500);
    fadeInAnimation.setFillAfter(true);
    mAnswerlabel.setAnimation(fadeInAnimation);
    }

    private void playsound(){
     MediaPlayer Player = MediaPlayer.create(this , R.raw .crystal_ball );
     Player.start();
     Player.setOnCompletionListener(new OnCompletionListener() {

        @Override
        public void onCompletion(MediaPlayer mp) {
            mp.release();
        }
    });
    }


    protected TextView setText(String string) {

        return null;
    }


    @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 void answerHandle() {
        String answer = mcrystall.getananswer();
        mAnswerlabel.setText(answer);
        animateCrystallBall();
        animateAnswer();
        playsound();
    }

      }