LocationListener/Provider funktioniert nicht

package com.example.homefinder;


import mutil.LoopList;


import android.app.Activity;
import android.content.Context;
import android.location.Location;
import android.location.LocationListener;
import android.location.LocationManager;
import android.location.LocationProvider;
import android.os.Bundle;


public class GPSAccumulator implements LocationListener
{
	private LocationManager locmanager;
	private LoopList<Location> locations;
	private int accum = 0;
	
	public GPSAccumulator(Context c)
	{
		locmanager = (LocationManager) c.getSystemService(Context.LOCATION_SERVICE);
		 if (!locmanager.isProviderEnabled(LocationManager.GPS_PROVIDER))
		 {
			 //System.exit(0);
			 accum = -1;
		 }
		 dab += "Provider enabled: "+locmanager.isProviderEnabled(LocationManager.GPS_PROVIDER)+"\n";
		 
		 locmanager.requestLocationUpdates(LocationManager.GPS_PROVIDER, 1000, 0, this);
		 locations = new LoopList<Location>();
	}
	
	public double getDistanceTravelled()
	{
		double d = 0;
		double c = 0;
		if ( locations.empty() ) return 0;
		
		Location lastOne = locations.current();
		Location currentOne;
		
		while ( !locations.last() )
		{
			currentOne = locations.next();
			
			locations.pushPointer();
			while( c < 3*currentOne.getAccuracy() && !locations.last())
			{
				currentOne = locations.next();
				c = currentOne.distanceTo(lastOne);
				
			}
			locations.reset();
			
			d += c;
			c = 0;
			lastOne = currentOne;
		}
		
		locations.reset();


		return d;
	}


	@Override
	public void onLocationChanged(Location location)
	{
		accum++;
		locations.add(location);
	}


	public int getLocationCount()
	{
		return accum;
	}
	
	public String getDebugText()
	{
		Location l = locmanager.getLastKnownLocation(LocationManager.GPS_PROVIDER);
		String s = "Längengrad: "+l.getAltitude()+" Breitengrad: "+l.getLatitude()+"\n"+dab;
		return s;
	}
	
	String dab ="";
	
	@Override
	public void onProviderDisabled(String provider)
	{
		// TODO Auto-generated method stub
		dab += "Provider disabled\n";
		
	}


	@Override
	public void onProviderEnabled(String provider)
	{
		// TODO Auto-generated method stub
		
	}


	@Override
	public void onStatusChanged(String provider, int status, Bundle extras)
	{
		// TODO Auto-generated method stub
		dab += "Provider status changed to: "+status+"\n";
		
	}
}