我现在有一项服务。它会检查GPS是否已启用,如果是GPS,它将获得GPS位置,我的地图可以缩放到该位置。它有getLastKnownLocation
。问题是,getLastKnownLocation
可能在几英里之外(就像我昨天尝试时那样)。
它首先运行GPS检查,因为它启用它不会运行网络检查位置。
有没有办法让它如果启用GPS,但是除了getLastKnownLcation()之外无法获得修复将默认为基于网络的位置?之后我会检查,如果网络没有启用或者lastKnownLocation太远,我可以检查Wifi。
以下是我的服务代码:
public class GPSTracker extends Service implements LocationListener {
private final Context mContext;
boolean isGPSEnabled = false;
boolean isNetworkEnabled = false;
boolean canGetLocation = false;
Location location;
double latitude;
double longitude;
//Minimum distance for update
private static final long MIN_DISTANCE_CHANGE_FOR_UPDATES = 10; //10 meters
// The minimum time between updates in milliseconds
private static final long MIN_TIME_BW_UPDATES = 1000 * 40; //40 seconds
protected LocationManager locationManager;
public GPSTracker(Context context) {
this.mContext = context;
getLocation();
}
public Location getLocation() {
Log.i("i", "Get location called");
locationManager = (LocationManager) mContext.getSystemService(LOCATION_SERVICE);
//Getting GPS status
isGPSEnabled = locationManager.isProviderEnabled(LocationManager.GPS_PROVIDER);
//Getting network status
isNetworkEnabled = locationManager.isProviderEnabled(LocationManager.NETWORK_PROVIDER);
this.canGetLocation = true;
if (isGPSEnabled) {
if (location == null) {
locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, MIN_TIME_BW_UPDATES, MIN_DISTANCE_CHANGE_FOR_UPDATES, this);
Log.d("GPS Enabled", "GPS Enabled");
if (locationManager != null) {
location = locationManager.getLastKnownLocation(LocationManager.GPS_PROVIDER);
if (location != null) {
latitude = location.getLatitude();
longitude = location.getLongitude();
Log.i("GPS_LOCATION", "Location: "+location.toString());
if(location.toString().contains("0.000000")) {
Log.i("Called", "Called inside");
isNetworkEnabled = true;
isGPSEnabled = false;
getLocation();
}
}
}
}
}
else if (isNetworkEnabled) {
Log.d("Network", "Network");
locationManager.requestLocationUpdates(LocationManager.NETWORK_PROVIDER, MIN_TIME_BW_UPDATES, MIN_DISTANCE_CHANGE_FOR_UPDATES, this);
if (locationManager != null) {
location = locationManager.getLastKnownLocation(LocationManager.NETWORK_PROVIDER);
if (location != null) {
latitude = location.getLatitude();
longitude = location.getLongitude();
Log.i("NETWORK_LOCATION", "Location: "+location.toString());
}
}
}
else if (!isGPSEnabled && !isNetworkEnabled) {
// no network provider is enabled and GPS is off.
Log.d("NOT ENABLED", "Use WIFI");
}
return location;
}
昨天发生的事情是我离家几英里远,有无线连接并启用了GPS,但发生了什么事,虽然我的位置通过Wifi,地图上的蓝点更新。它不会放大它。由于GPS已经启用(但无法修复),它沿着那条路走下去,并且LastKnownLocation()
已经回到了我家。即使蓝点是正确的,它仍然缩放到我最后的位置。
我有没有办法让它检查GPS但不使用LastKnownLocation
?它默认为网络检查,然后网络检查将不使用lastknownLocation
,它将默认为Wifi。如果需要,Wifi可以有LastKnownLocation。实际上我只想在Wifi阶段获得lastKnownLocation
作为最后的手段。
希望有人可以帮助我。我认为这不如从代码中删除lastKnownLocation
那么简单。
感谢您提供的任何帮助。
答案 0 :(得分:1)
有各种各样的方法可以做到这一点。这里有一些提示:
getProvider()
向提供商提供,检查您是否拥有最高优先级,然后在辅助服务器上工作。您可能需要仔细查看Location Strategies,特别是isBetterLocation函数。你可能想要这样的东西,虽然你需要调整它以满足你的需要。
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);
}