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copied!<p>Here is additional information for other answers.</p> <p>Since Android has</p> <pre><code>GPS_PROVIDER and NETWORK_PROVIDER </code></pre> <p>you can register to both and start fetch events from <code>onLocationChanged(Location location)</code> from two at the same time. So far so good. Now the question do we need two results or we should take the best. As I know <code>GPS_PROVIDER</code> results have better accuracy than <code>NETWORK_PROVIDER</code>.</p> <p>Let's define <code>Location</code> field:</p> <pre><code>private Location currentBestLocation = null; </code></pre> <p>Before we start listen on <em>Location</em> change we will implement the following method. This method returns the last known location, between the GPS and the network one. For this method newer is best.</p> <pre><code>/** * @return the last know best location */ private Location getLastBestLocation() { Location locationGPS = mLocationManager.getLastKnownLocation(LocationManager.GPS_PROVIDER); Location locationNet = mLocationManager.getLastKnownLocation(LocationManager.NETWORK_PROVIDER); long GPSLocationTime = 0; if (null != locationGPS) { GPSLocationTime = locationGPS.getTime(); } long NetLocationTime = 0; if (null != locationNet) { NetLocationTime = locationNet.getTime(); } if ( 0 < GPSLocationTime - NetLocationTime ) { return locationGPS; } else { return locationNet; } } </code></pre> <p>Each time when we retrieve a new location we will compare it with our previous result.</p> <pre><code>... static final int TWO_MINUTES = 1000 * 60 * 2; ... </code></pre> <p>I add a new method to <code>onLocationChanged</code>:</p> <pre><code>@override public void onLocationChanged(Location location) { makeUseOfNewLocation(location); if(currentBestLocation == null){ currentBestLocation = location; } .... } /** * This method modify the last know good location according to the arguments. * * @param location The possible new location. */ void makeUseOfNewLocation(Location location) { if ( isBetterLocation(location, currentBestLocation) ) { currentBestLocation = location; } } .... /** Determines whether one location reading is better than the current location fix * @param location The new location that you want to evaluate * @param currentBestLocation The current location fix, to which you want to compare the new one. */ protected boolean isBetterLocation(Location location, Location currentBestLocation) { if (currentBestLocation == null) { // A new location is always better than no location return true; } // Check whether the new location fix is newer or older long timeDelta = location.getTime() - currentBestLocation.getTime(); boolean isSignificantlyNewer = timeDelta > TWO_MINUTES; boolean isSignificantlyOlder = timeDelta < -TWO_MINUTES; boolean isNewer = timeDelta > 0; // If it's been more than two minutes since the current location, use the new location, // because the user has likely moved. if (isSignificantlyNewer) { return true; // If the new location is more than two minutes older, it must be worse. } else if (isSignificantlyOlder) { return false; } // Check whether the new location fix is more or less accurate int accuracyDelta = (int) (location.getAccuracy() - currentBestLocation.getAccuracy()); boolean isLessAccurate = accuracyDelta > 0; boolean isMoreAccurate = accuracyDelta < 0; boolean isSignificantlyLessAccurate = accuracyDelta > 200; // Check if the old and new location are from the same provider boolean isFromSameProvider = isSameProvider(location.getProvider(), currentBestLocation.getProvider()); // Determine location quality using a combination of timeliness and accuracy if (isMoreAccurate) { return true; } else if (isNewer && !isLessAccurate) { return true; } else if (isNewer && !isSignificantlyLessAccurate && isFromSameProvider) { return true; } return false; } /** Checks whether two providers are the same */ private boolean isSameProvider(String provider1, String provider2) { if (provider1 == null) { return provider2 == null; } return provider1.equals(provider2); } .... </code></pre>

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