How can I get the values from the "public void onSensorChanged(SensorEvent event) " to another?

Hi!! I'm making an application on Android and I'm using the accelerometer sensor of my phone.

Part of the code is:

Code (Text):

1.  
2.  
3.     public class OtroacelbtActivity extends Activity implements SensorEventListener {
4.     private float x = 0, y = 0, z = 0;
5.    
6.      @Override
7.         public void onCreate(Bundle savedInstanceState) {
8.             super.onCreate(savedInstanceState);
9.     }
10.    
11.     @Override
12.         protected void onResume() {
13.             super.onResume();
14.             SensorManager sm = (SensorManager) getSystemService(SENSOR_SERVICE);
15.             List<Sensor> sensors = sm.getSensorList(Sensor.TYPE_ACCELEROMETER);
16.             if (sensors.size() > 0) {
17.              sm.registerListener(this, sensors.get(0), SensorManager.SENSOR_DELAY_UI );
18.             }
19.     }
20.    
21.     @Override
22.     public void onAccuracyChanged(Sensor sensor, int accuracy) {}
23.    
24.     @Override
25.     public void onSensorChanged(SensorEvent event) {
26.             synchronized (this) {
27.                
28.             String message=null;
29.            
30.                
31.                 x = event.values[0];
32.                 y = event.values[1];
33.                 z = event.values[2];
34.     }
35.     }
36. }

I want to use the x,y and z values on another method, but even they are global variables, if I call them just like that on the other method, thee only give the "null" value (cause it's a void method).

How can I do it???

Thanks.