我的问题是获得经纬度。
在模拟器中我使用:Lat - 54.035795,Long - 21.760029。但是当我拨打getLatitude()
或getLongitude()
时,我得到54.0和21.0
所以我无法获得两点之间的准确距离。
有什么问题?
请帮帮我。
public final class LocationGpsListener implements LocationListener
{
private final Context mContext;
public boolean isGPSEnabled = false;
boolean isNetworkEnabled = false;
boolean canGetLocation = false;
Location location;
Double latitude;
Double longitude;
private static final long MIN_DISTANCE_CHANGE_FOR_UPDATES = 10;
private static final long MIN_TIME_BW_UPDATES = 1000 * 60 * 1;
protected LocationManager locationManager;
public LocationGpsListener(Context context) {
this.mContext = context;
getLocation();
}
public Location getLocation() {
try {
locationManager = (LocationManager) mContext.getSystemService(Context.LOCATION_SERVICE);
isGPSEnabled = locationManager.isProviderEnabled(LocationManager.GPS_PROVIDER);
Log.v("isGPSEnabled", "=" + isGPSEnabled);
isNetworkEnabled = locationManager.isProviderEnabled(LocationManager.NETWORK_PROVIDER);
Log.v("isNetworkEnabled", "=" + isNetworkEnabled);
if (isGPSEnabled == false && isNetworkEnabled == false) {
} else {
this.canGetLocation = true;
if (isNetworkEnabled) {
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();
}
}
}
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();
}
}
}
}
}
} catch (Exception e) {
e.printStackTrace();
}
return location;
}
public void stopUsingGPS() {
if (locationManager != null) {
locationManager.removeUpdates(LocationGpsListener.this);
}
}
public double getLatitude() {
if (location != null) {
latitude = location.getLatitude();
}
return latitude;
}
public double getLongitude() {
if (location != null) {
longitude = location.getLongitude();
}
return longitude;
}
public boolean canGetLocation() {
return this.canGetLocation;
}
public void showSettingsAlert() {
AlertDialog.Builder alertDialog = new AlertDialog.Builder(mContext);
alertDialog.setTitle("GPS");
alertDialog.setMessage("GPS is ENABLED:");
alertDialog.setPositiveButton("Settings",
new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int which) {
Intent intent = new Intent(
Settings.ACTION_LOCATION_SOURCE_SETTINGS);
mContext.startActivity(intent);
}
});
alertDialog.setNegativeButton("Cancel",
new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int which) {
dialog.cancel();
}
});
alertDialog.show();
}
@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) {
}
}
我使用:
mGPS = new LocationGpsListener(this);
if(mGPS.canGetLocation ){
longitude = mGPS.getLatitude();
latitude = mGPS.getLongitude();
}else{
longitude = 21.230000;
latitude = 53.230000;
}
Location l1 = new Location("lok a");
l1.setLatitude(latitude);
l1.setLongitude(longitude);
Location l2 = new Location("lok b");
l2.setLatitude(54.035679);
l2.setLongitude(21.784879);
答案 0 :(得分:0)
我无法重现您的问题,但我可以为您提供代码的改进版本:
import android.content.Context;
import android.location.Location;
import android.location.LocationListener;
import android.location.LocationManager;
import android.os.Bundle;
public final class LocationGpsListener implements LocationListener {
public boolean isGPSEnabled = false;
private Location location;
private static final long MIN_DISTANCE_CHANGE_FOR_UPDATES = 10;
private static final long MIN_TIME_BW_UPDATES = 1000 * 60 * 1;
protected LocationManager locationManager;
public LocationGpsListener(Context context) {
locationManager = (LocationManager) context.getSystemService(Context.LOCATION_SERVICE);
// TODO check is network/gps is enabled and display the system settings
// see
// https://github.com/unchiujar/Umbra/blob/master/src/main/java/org/unchiujar/umbra/activities/FogOfExplore.java#L599
locationManager.requestLocationUpdates(LocationManager.NETWORK_PROVIDER,
MIN_TIME_BW_UPDATES, MIN_DISTANCE_CHANGE_FOR_UPDATES, this);
locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, MIN_TIME_BW_UPDATES,
MIN_DISTANCE_CHANGE_FOR_UPDATES, this);
location = new Location("fake");
location.setLatitude(0);
location.setLongitude(0);
}
public void stopLocationUpdates() {
if (locationManager != null) {
locationManager.removeUpdates(LocationGpsListener.this);
}
}
public double getLatitude() {
return location.getLatitude();
}
public double getLongitude() {
return location.getLongitude();
}
@Override
public void onLocationChanged(Location location) {
this.location = location;
}
@Override
public void onProviderDisabled(String provider) {
// NO-OP
}
@Override
public void onProviderEnabled(String provider) {
// NO-OP
}
@Override
public void onStatusChanged(String provider, int status, Bundle extras) {
// NO-OP
}
}
您发布的代码没有正确使用侦听器模式(我也没有,但它是一个改进)。位置逻辑应该在onLocationChanged
方法中,而不是在其他地方的随机方法中。在
我建议您阅读:http://www.vogella.com/articles/AndroidLocationAPI/article.html
此外,永远不要使用catch(Exception e)
它会导致各种非常难以追踪的错误。
Why is the Catch(Exception) almost always a bad Idea?
http://today.java.net/article/2006/04/04/exception-handling-antipatterns#catchingException
答案 1 :(得分:0)
我认为问题在于您对使用的位置提供程序不够具体,而且您正在恢复课程准确性。
使用Criteria
获取最佳位置信息提供商以设置所需的准确度:
locationManager = (LocationManager) mContext.getSystemService(Context.LOCATION_SERVICE);
Criteria criteria = new Criteria();
criteria.setAccuracy(Criteria.ACCURACY_HIGH);
locationManager.getBestProvider(criteria, true);
或者也许使用以标准作为参数的requestLocationUpdates
覆盖。
检查上述内容,并在清单中另外显示"android.permission.ACCESS_FINE_LOCATION"
。
答案 2 :(得分:0)
我的问题是在GPS设置良好值之前获取位置
我有一个有趣的问题(当应用程序崩溃时): “请记住,检查设备是否有GPS”:)