我需要在两个位置之间获得距离，但我需要像图中的蓝线一样得到距离。
我接下来尝试：
public double getDistance(LatLng LatLng1, LatLng LatLng2) {
double distance = 0;
Location locationA = new Location("A");
locationA.setLatitude(LatLng1.latitude);
locationA.setLongitude(LatLng1.longitude);
Location locationB = new Location("B");
locationB.setLatitude(LatLng2.latitude);
locationB.setLongitude(LatLng2.longitude);
distance = locationA.distanceTo(locationB);
return distance;
}
但我得到红线距离。
使用Google Maps Directions API。您需要通过HTTP请求指示。您可以直接从Android或通过自己的服务器执行此操作。
例如，来自Montreal to Toronto的路线：
GET http://maps.googleapis.com/maps/api/directions/json?origin=Toronto&destination=Montreal&sensor=false
你最终会得到一些JSON。在routes[].legs[].distance中，你会得到一个这样的对象：
"legs" : [
{
"distance" : {
"text" : "542 km",
"value" : 542389
},
您还可以直接从响应对象获取折线信息。
要查找2个位置之间的距离：
正如克里斯布罗德福特是正确的，要解析返回的JSON routes[].legs[].distance
"legs" : [
{
"distance" : {
"text" : "542 km",
"value" : 542389
}
使用：
final JSONObject json = new JSONObject(result);
JSONArray routeArray = json.getJSONArray("routes");
JSONObject routes = routeArray.getJSONObject(0);
JSONArray newTempARr = routes.getJSONArray("legs");
JSONObject newDisTimeOb = newTempARr.getJSONObject(0);
JSONObject distOb = newDisTimeOb.getJSONObject("distance");
JSONObject timeOb = newDisTimeOb.getJSONObject("duration");
Log.i("Diatance :", distOb.getString("text"));
Log.i("Time :", timeOb.getString("text"));
您可以在android中使用以下Location方法（如果你有lat，两个位置的长度），该方法返回以米为单位的近似距离。
public static void distanceBetween (double startLatitude, double startLongitude, double endLatitude, double endLongitude, float[] results)
说明：
计算两个位置之间的近似距离，以及它们之间最短路径的初始和最终方位。使用WGS84椭圆体定义距离和方位。
计算出的距离存储在results[0]中。如果结果的长度为2或更大，则初始轴承存储在results[1]中。如果结果长度为3或更大，则最终轴承存储在results[2]中。参数：
startLatitude - 起始纬度
startLongitude起始经度
endLatitude结束纬度
endLongitude结束经度
得到一个浮点数组来保存结果
用这个：
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;
}
public String getDistance(final double lat1, final double lon1, final double lat2, final double lon2){
String parsedDistance;
String response;
Thread thread=new Thread(new Runnable() {
@Override
public void run() {
try {
URL url = new URL("http://maps.googleapis.com/maps/api/directions/json?origin=" + lat1 + "," + lon1 + "&destination=" + lat2 + "," + lon2 + "&sensor=false&units=metric&mode=driving");
final HttpURLConnection conn = (HttpURLConnection) url.openConnection();
conn.setRequestMethod("POST");
InputStream in = new BufferedInputStream(conn.getInputStream());
response = org.apache.commons.io.IOUtils.toString(in, "UTF-8");
JSONObject jsonObject = new JSONObject(response);
JSONArray array = jsonObject.getJSONArray("routes");
JSONObject routes = array.getJSONObject(0);
JSONArray legs = routes.getJSONArray("legs");
JSONObject steps = legs.getJSONObject(0);
JSONObject distance = steps.getJSONObject("distance");
parsedDistance=distance.getString("text");
} catch (ProtocolException e) {
e.printStackTrace();
} catch (MalformedURLException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
} catch (JSONException e) {
e.printStackTrace();
}
}
});
thread.start();
try {
thread.join();
} catch (InterruptedException e) {
e.printStackTrace();
}
return parsedDistance;
}
试试这个：
private double calculateDistance(double fromLong, double fromLat,
double toLong, double toLat) {
double d2r = Math.PI / 180;
double dLong = (toLong - fromLong) * d2r;
double dLat = (toLat - fromLat) * d2r;
double a = Math.pow(Math.sin(dLat / 2.0), 2) + Math.cos(fromLat * d2r)
* Math.cos(toLat * d2r) * Math.pow(Math.sin(dLong / 2.0), 2);
double c = 2 * Math.atan2(Math.sqrt(a), Math.sqrt(1 - a));
double d = 6367000 * c;
return Math.round(d);
}
希望这可以帮助。
你可以使用这段代码
public double CalculationByDistance(LatLng StartP, LatLng EndP) {
int Radius = 6371;// radius of earth in Km
double lat1 = StartP.latitude;
double lat2 = EndP.latitude;
double lon1 = StartP.longitude;
double lon2 = EndP.longitude;
double dLat = Math.toRadians(lat2 - lat1);
double dLon = Math.toRadians(lon2 - lon1);
double a = Math.sin(dLat / 2) * Math.sin(dLat / 2)
+ Math.cos(Math.toRadians(lat1))
* Math.cos(Math.toRadians(lat2)) * Math.sin(dLon / 2)
* Math.sin(dLon / 2);
double c = 2 * Math.asin(Math.sqrt(a));
double valueResult = Radius * c;
double km = valueResult / 1;
DecimalFormat newFormat = new DecimalFormat("####");
int kmInDec = Integer.valueOf(newFormat.format(km));
double meter = valueResult % 1000;
int meterInDec = Integer.valueOf(newFormat.format(meter));
Log.i("Radius Value", "" + valueResult + " KM " + kmInDec
+ " Meter " + meterInDec);
return Radius * c;
}
试试这段代码
public double CalculationByDistance(LatLng StartP, LatLng EndP) {
int Radius = 6371;// radius of earth in Km
double lat1 = StartP.latitude;
double lat2 = EndP.latitude;
double lon1 = StartP.longitude;
double lon2 = EndP.longitude;
double dLat = Math.toRadians(lat2 - lat1);
double dLon = Math.toRadians(lon2 - lon1);
double a = Math.sin(dLat / 2) * Math.sin(dLat / 2)
+ Math.cos(Math.toRadians(lat1))
* Math.cos(Math.toRadians(lat2)) * Math.sin(dLon / 2)
* Math.sin(dLon / 2);
double c = 2 * Math.asin(Math.sqrt(a));
double valueResult = Radius * c;
double km = valueResult / 1;
DecimalFormat newFormat = new DecimalFormat("####");
int kmInDec = Integer.valueOf(newFormat.format(km));
double meter = valueResult % 1000;
int meterInDec = Integer.valueOf(newFormat.format(meter));
Log.i("Radius Value", "" + valueResult + " KM " + kmInDec
+ " Meter " + meterInDec);
return Radius * c;
}
private String getDistance(double lat2, double lon2){
Location loc1 = new Location("A");
loc1.setLatitude("A1");
loc1.setLongitude("B1");
Location loc2 = new Location("B");
loc2.setLatitude(lat2);
loc2.setLongitude(lon2);
float distanceInMeters = loc1.distanceTo(loc2);
float mile = distanceInMeters / 1609.34f;
String sm = String.format("%.2f", mile);
return sm;
}