我是新手。我写了一个类,它实现服务并使用gps,但位置总是空的。所有需要的权限都被写入并且服务正常启动,我可以绑定到它,但检索到的位置总是空的,它永远不会进入onLocationChanged(Location location)。有人可以帮忙吗?
public class GPSService extends Service {
private static final String TAG = "GPS_SERVICE";
private LocationManager mLocationManager = null;
private static final int LOCATION_INTERVAL = 1000;
private static final float LOCATION_DISTANCE = 10f;
Location currentLocation;
private class LocationListener implements android.location.LocationListener{
Location mLastLocation;
public LocationListener(String provider)
{
Log.e(TAG, "LocationListener " + provider);
mLastLocation = new Location(provider);
}
public void onLocationChanged(Location location)
{
Log.e(TAG, "onLocationChanged: " + location);
if (location != null){
mLastLocation.set(location);
currentLocation = mLastLocation;
}
}
public void onProviderDisabled(String provider)
{
Log.e(TAG, "onProviderDisabled: " + provider);
}
public void onProviderEnabled(String provider)
{
Log.e(TAG, "onProviderEnabled: " + provider);
}
public void onStatusChanged(String provider, int status, Bundle extras)
{
Log.e(TAG, "onStatusChanged: " + provider);
}
}
LocationListener[] mLocationListeners = new LocationListener[] {
new LocationListener(LocationManager.GPS_PROVIDER),
new LocationListener(LocationManager.NETWORK_PROVIDER)
};
private IBinder mBinder = new GPSServiceBinder();
public class GPSServiceBinder extends Binder {
public GPSService getServerInstance() {
return GPSService.this;
}
}
public int onStartCommand(Intent intent, int flags, int startId)
{
Log.e(TAG, "onStartCommand");
super.onStartCommand(intent, flags, startId);
return START_STICKY;
}
public IBinder onBind(Intent intent) {
return mBinder;
}
int minTime = 6000;
float minDistance = 15;
public void onCreate()
{
Log.e(TAG, "onCreate");
initializeLocationManager();
try {
mLocationManager.requestLocationUpdates(
LocationManager.NETWORK_PROVIDER, LOCATION_INTERVAL, LOCATION_DISTANCE,
mLocationListeners[1]);
} catch (java.lang.SecurityException ex) {
Log.i(TAG, "fail to request location update, ignore", ex);
} catch (IllegalArgumentException ex) {
Log.d(TAG, "network provider does not exist, " + ex.getMessage());
}
try {
mLocationManager.requestLocationUpdates(
LocationManager.GPS_PROVIDER, LOCATION_INTERVAL, LOCATION_DISTANCE,
mLocationListeners[0]);
} catch (java.lang.SecurityException ex) {
Log.i(TAG, "fail to request location update, ignore", ex);
} catch (IllegalArgumentException ex) {
Log.d(TAG, "gps provider does not exist " + ex.getMessage());
}
}
public Location getLocation()
{
return currentLocation;
}
public void onDestroy()
{
Log.e(TAG, "onDestroy");
super.onDestroy();
if (mLocationManager != null) {
for (int i = 0; i < mLocationListeners.length; i++) {
try {
mLocationManager.removeUpdates(mLocationListeners[i]);
} catch (Exception ex) {
Log.i(TAG, "fail to remove location listners, ignore", ex);
}
}
}
}
private void initializeLocationManager() {
Log.e(TAG, "initializeLocationManager");
if (mLocationManager == null) {
mLocationManager = (LocationManager) getApplicationContext().getSystemService(Context.LOCATION_SERVICE);
}
}
}