这里我的代码我在下面的代码中用来计算两个位置之间使用纬度和经度的距离。这是错误的距离。有时候变得正确,有时会变得无关紧要。
我们从数据库获取lat1和lng1。
//getting lat2 and lng2 from GPS as below
public class MyLocationListener implements LocationListener {
@Override
public void onLocationChanged(Location loc)
{
lat2=loc.getLatitude();
lng2=loc.getLongitude();
String Text = "My current location is: " +"Latitud = "+ loc.getLatitude() +"Longitud = " + loc.getLongitude();
//System.out.println("Lat & Lang form Loc"+Text);
//Toast.makeText( getApplicationContext(), Text,Toast.LENGTH_SHORT).show();
}
@Override
public void onProviderDisabled(String provider)
{
}
@Override
public void onProviderEnabled(String provider)
{
}
@Override
public void onStatusChanged(String provider, int status, Bundle extras)
{
}
//Calculating distance
double earthRadius = 3958.75;
double dLat = Math.toRadians(lat1-lat2);
double dLng = Math.toRadians(lng1-lng2);
double a = Math.sin(dLat/2) * Math.sin(dLat/2) +
Math.cos(Math.toRadians(lat2)) * Math.cos(Math.toRadians(lat1)) *
Math.sin(dLng/2) * Math.sin(dLng/2);
double c = 2 * Math.atan2(Math.sqrt(a), Math.sqrt(1-a));
double dist = earthRadius * c;
答案 0 :(得分:67)
有一种android.location.Location.distanceBetween()
方法可以很好地完成这项工作。
答案 1 :(得分:51)
试试这段代码。
startPoint.distanceTo(endPoint)函数返回这些位置之间的距离(以米为单位)。
Location startPoint=new Location("locationA");
startPoint.setLatitude(17.372102);
startPoint.setLongitude(78.484196);
Location endPoint=new Location("locationA");
endPoint.setLatitude(17.375775);
endPoint.setLongitude(78.469218);
double distance=startPoint.distanceTo(endPoint);
此处“距离”是 Meters 中我们要求的结果。我希望它适用于android。
答案 2 :(得分:43)
以千米(km)为距离
private double distance(double lat1, double lon1, double lat2, double lon2) {
double theta = lon1 - lon2;
double dist = Math.sin(deg2rad(lat1))
* Math.sin(deg2rad(lat2))
+ Math.cos(deg2rad(lat1))
* Math.cos(deg2rad(lat2))
* Math.cos(deg2rad(theta));
dist = Math.acos(dist);
dist = rad2deg(dist);
dist = dist * 60 * 1.1515;
return (dist);
}
private double deg2rad(double deg) {
return (deg * Math.PI / 180.0);
}
private double rad2deg(double rad) {
return (rad * 180.0 / Math.PI);
}
答案 3 :(得分:7)
:
compile 'com.google.maps.android:android-maps-utils:0.4'
然后:
public static Double distanceBetween(LatLng point1, LatLng point2) {
if (point1 == null || point2 == null) {
return null;
}
return SphericalUtil.computeDistanceBetween(point1, point2);
}
答案 4 :(得分:5)
如果您有两个位置对象Location loc1
和Location loc2
,那么
float distance = loc1.distanceTo(loc2);
如果您有经度和纬度值,则使用静态distanceBetween()
函数
float[] results = new float[1];
Location.distanceBetween(startLatitude, startLongitude,
endLatitude, endLongitude, results);
float distance = results[0];
答案 5 :(得分:2)
private String getDistanceOnRoad(double latitude, double longitude,
double prelatitute, double prelongitude) {
String result_in_kms = "";
String url = "http://maps.google.com/maps/api/directions/xml?origin="
+ latitude + "," + longitude + "&destination=" + prelatitute
+ "," + prelongitude + "&sensor=false&units=metric";
String tag[] = { "text" };
HttpResponse response = null;
try {
HttpClient httpClient = new DefaultHttpClient();
HttpContext localContext = new BasicHttpContext();
HttpPost httpPost = new HttpPost(url);
response = httpClient.execute(httpPost, localContext);
InputStream is = response.getEntity().getContent();
DocumentBuilder builder = DocumentBuilderFactory.newInstance()
.newDocumentBuilder();
Document doc = builder.parse(is);
if (doc != null) {
NodeList nl;
ArrayList args = new ArrayList();
for (String s : tag) {
nl = doc.getElementsByTagName(s);
if (nl.getLength() > 0) {
Node node = nl.item(nl.getLength() - 1);
args.add(node.getTextContent());
} else {
args.add(" - ");
}
}
result_in_kms = String.format("%s", args.get(0));
}
} catch (Exception e) {
e.printStackTrace();
}
return result_in_kms;
}
答案 6 :(得分:1)
为什么要编写自己计算距离的代码?
检查Location类
中的api答案 7 :(得分:1)
private float distanceFrom_in_Km(float lat1, float lng1, float lat2, float lng2) {
if (lat1== null || lng1== null || lat2== null || lng2== null)
{
return null;
}
double earthRadius = 6371000; //meters
double dLat = Math.toRadians(lat2-lat1);
double dLng = Math.toRadians(lng2-lng1);
double a = Math.sin(dLat/2) * Math.sin(dLat/2) +
Math.cos(Math.toRadians(lat1)) * Math.cos(Math.toRadians(lat2)) *
Math.sin(dLng/2) * Math.sin(dLng/2);
double c = 2 * Math.atan2(Math.sqrt(a), Math.sqrt(1-a));
float dist = (float) (earthRadius * c);
return dist;
}
答案 8 :(得分:1)
从经纬度获取知识
public static float getKmFromLatLong(float lat1, float lng1, float lat2, float lng2){
Location loc1 = new Location("");
loc1.setLatitude(lat1);
loc1.setLongitude(lng1);
Location loc2 = new Location("");
loc2.setLatitude(lat2);
loc2.setLongitude(lng2);
float distanceInMeters = loc1.distanceTo(loc2);
return distanceInMeters/1000;
}
答案 9 :(得分:1)
使用以下方法计算两个不同位置的距离。
Observable request1 = getRequest1();
Observable request2 = getRequest2();
Observable.zip(request1, request2,
new BiFunction<Something, Something, Pair<Something, Something>() {
@Override
public Pair<Something, Something> apply(Something response1, Something response2) {
return new Pair(response1, response2); // you can create a custom object to handle all of the responses
}
})
.map( // do something with your responses )
答案 10 :(得分:0)
您应该使用Haversine距离公式
Haversine Formulas用于计算地球上两点之间的距离。
public void haversine(double lat1, double lon1, double lat2, double lon2) {
double Rad = 6372.8; //Earth's Radius In kilometers
// TODO Auto-generated method stub
double dLat = Math.toRadians(lat2 - lat1);
double dLon = Math.toRadians(lon2 - lon1);
lat1 = Math.toRadians(lat1);
lat2 = Math.toRadians(lat2);
double a = Math.sin(dLat / 2) * Math.sin(dLat / 2) + Math.sin(dLon / 2) * Math.sin(dLon / 2) * Math.cos(lat1) * Math.cos(lat2);
double c = 2 * Math.asin(Math.sqrt(a));
haverdistanceKM = Rad * c;
}
答案 11 :(得分:0)
public float getMesureLatLang(double lat,double lang) {
Location loc1 = new Location("");
loc1.setLatitude(getLatitute());// current latitude
loc1.setLongitude(getLangitute());//current Longitude
Location loc2 = new Location("");
loc2.setLatitude(lat);
loc2.setLongitude(lang);
return loc1.distanceTo(loc2);
// return distance(getLatitute(),getLangitute(),lat,lang);
}
答案 12 :(得分:0)
尝试下面的方法代码来获取两个位置之间的距离(以米为单位),希望对您有帮助
public static double distance(LatLng start, LatLng end){
try {
Location location1 = new Location("locationA");
location1.setLatitude(start.latitude);
location1.setLongitude(start.longitude);
Location location2 = new Location("locationB");
location2.setLatitude(end.latitude);
location2.setLongitude(end.longitude);
double distance = location1.distanceTo(location2);
return distance;
} catch (Exception e) {
e.printStackTrace();
}
return 0;
}