如何在Android手机中显示GPS的当前位置？

Question

我试图从下面的代码中获取当前位置。但它无法正常工作。我无法找到问题。当它在模拟器上部署时，它显示goolemaps无法正常工作。当它在设备上部署时，它显示强制关闭。任何人都可以帮助我吗？

package com.example.googlemaps;

import android.content.Context;
import android.location.Location;
import android.location.LocationListener;
import android.location.LocationManager;
import android.os.Bundle;
import android.widget.Toast;

import com.google.android.maps.MapActivity;
import com.google.android.maps.MapView;

public class GoogleMapsActivity extends MapActivity implements LocationListener {

private LocationManager locManager;

/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    //fetch the map view from the layout
    MapView mapView = (MapView) findViewById(R.id.mapview);

    //make available zoom controls
    mapView.setBuiltInZoomControls(true);

    // invalidate the map in order to show changes
    mapView.invalidate();


    // Use the location manager through GPS
    locManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
    locManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, 0,
            0, this);

    //get the current location (last known location) from the location manager
    Location location = locManager
            .getLastKnownLocation(LocationManager.GPS_PROVIDER);


        //if location found display as a toast the current latitude and longitude
    if (location != null) {

        Toast.makeText(
                this,
                "Current location:\nLatitude: " + location.getLatitude()
                        + "\n" + "Longitude: " + location.getLongitude(),
                Toast.LENGTH_LONG).show();
    } else {

        Toast.makeText(this, "Cannot fetch current location!",
                Toast.LENGTH_LONG).show();
    }

  //when the current location is found – stop listening for updates (preserves     battery)
    locManager.removeUpdates(this);
}

@Override
protected boolean isRouteDisplayed() {
    return false;

}

/* When the activity starts up, request updates */
@Override
protected void onResume() {
    super.onResume();
    locManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, 0,
            0, this);
}

@Override
protected void onPause() {
    super.onPause();
    locManager.removeUpdates(this); //activity pauses => stop listening for updates
}
    @Override
public void onLocationChanged(Location location) {

}


@Override
public void onProviderDisabled(String provider) {

}

@Override
public void onProviderEnabled(String provider) {

}

@Override
public void onStatusChanged(String provider, int status, Bundle extras) {

}

}