Czujnik światła

package com.example.czujnik;

import java.io.IOException;
import android.hardware.Sensor;
import android.hardware.SensorEvent;
import android.hardware.SensorEventListener;
import android.hardware.SensorManager;
import android.media.MediaPlayer;
import android.os.Bundle;
import android.os.Environment;
import android.app.Activity;
import android.content.Context;
import android.view.Menu;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;

public class MainActivity extends Activity implements SensorEventListener{
	private SensorManager mSensorManager;
	private Sensor mCzujnikSwiatla;
	public MediaPlayer odtwarzaczAudio=null;
	public TextView eTxt;
	public int czy=0;
	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.activity_main);
		
		Button bOn=(Button)findViewById(R.id.buttonOn);
		eTxt=(EditText)findViewById(R.id.editTextTxt);
		mSensorManager = (SensorManager) getSystemService(Context.SENSOR_SERVICE);
		mCzujnikSwiatla = mSensorManager.getDefaultSensor(Sensor.TYPE_LIGHT);
		mSensorManager.registerListener(this, mCzujnikSwiatla, SensorManager.SENSOR_DELAY_NORMAL);
		
	bOn.setOnClickListener(new OnClickListener() {
		
		@Override
		public void onClick(View v) {

			odtwarzaczAudio=new MediaPlayer();
			try {
			odtwarzaczAudio.setDataSource(Environment.getExternalStorageDirectory().getPath()+"/"+"1.mp3");
			} catch (IllegalArgumentException e1) {
				e1.printStackTrace();
			} catch (IllegalStateException e1) {
				e1.printStackTrace();
			} catch (IOException e1) {
				e1.printStackTrace();
			}
			
				try {
					odtwarzaczAudio.prepare();
				} catch (IllegalStateException e) {
					e.printStackTrace();
				} catch (IOException e) {
					e.printStackTrace();
				}
			odtwarzaczAudio.start();
			czy=1;
		}
	});	
	
	}

	protected void onResume() {
		super.onResume();
		mSensorManager.registerListener(this, mCzujnikSwiatla,SensorManager.SENSOR_DELAY_NORMAL);
	}
	
	protected void onPause() {
		super.onPause();
		mSensorManager.unregisterListener(this);
	}
	
	public void onSensorChanged(SensorEvent event) {
		
		float x=event.values[0];
		String X=String.valueOf(x);
		eTxt.setText(X);
		
		if(odtwarzaczAudio!=null && X.equals("10.0") && czy==1)
		{
			czy=0;
			odtwarzaczAudio.stop();
			odtwarzaczAudio.release();
		}	
	}
	
	@Override
	public boolean onCreateOptionsMenu(Menu menu) {
		getMenuInflater().inflate(R.menu.main, menu);
		return true;
	}

	@Override
	public void onAccuracyChanged(Sensor sensor, int accuracy) {}
}