要在谷歌地图上计算距离，您可以使用方向API。这是最简单的方法之一。要从谷歌服务器获取数据，您可以使用Retrofit或Volley。两者都有各自的优势。看看下面的代码，我使用了改造来实现它:

private void build_retrofit_and_get_response(String type) {

    String url = "https://maps.googleapis.com/maps/";

    Retrofit retrofit = new Retrofit.Builder()
            .baseUrl(url)
            .addConverterFactory(GsonConverterFactory.create())
            .build();

    RetrofitMaps service = retrofit.create(RetrofitMaps.class);

    Call<Example> call = service.getDistanceDuration("metric", origin.latitude + "," + origin.longitude,dest.latitude + "," + dest.longitude, type);

    call.enqueue(new Callback<Example>() {
        @Override
        public void onResponse(Response<Example> response, Retrofit retrofit) {

            try {
                //Remove previous line from map
                if (line != null) {
                    line.remove();
                }
                // This loop will go through all the results and add marker on each location.
                for (int i = 0; i < response.body().getRoutes().size(); i++) {
                    String distance = response.body().getRoutes().get(i).getLegs().get(i).getDistance().getText();
                    String time = response.body().getRoutes().get(i).getLegs().get(i).getDuration().getText();
                    ShowDistanceDuration.setText("Distance:" + distance + ", Duration:" + time);
                    String encodedString = response.body().getRoutes().get(0).getOverviewPolyline().getPoints();
                    List<LatLng> list = decodePoly(encodedString);
                    line = mMap.addPolyline(new PolylineOptions()
                                    .addAll(list)
                                    .width(20)
                                    .color(Color.RED)
                                    .geodesic(true)
                    );
                }
            } catch (Exception e) {
                Log.d("onResponse", "There is an error");
                e.printStackTrace();
            }
        }

        @Override
        public void onFailure(Throwable t) {
            Log.d("onFailure", t.toString());
        }
    });

}

上面是用于计算距离的函数build_retrofit_and_get_response的代码。下面是对应的改装界面:

package com.androidtutorialpoint.googlemapsdistancecalculator;


import com.androidtutorialpoint.googlemapsdistancecalculator.POJO.Example;

import retrofit.Call;
import retrofit.http.GET;
import retrofit.http.Query;

public interface RetrofitMaps {


/*
 * Retrofit get annotation with our URL
 * And our method that will return us details of student.
 */
@GET("api/directions/json?key=AIzaSyC22GfkHu9FdgT9SwdCWMwKX1a4aohGifM")
Call<Example> getDistanceDuration(@Query("units") String units, @Query("origin") String origin, @Query("destination") String destination, @Query("mode") String mode);

}

我希望这能解释你的问题。祝一切顺利:)

来源:谷歌地图距离计算器

示例使用GPS的纬度/经度2个点。

var latitude1 = 39.46;
var longitude1 = -0.36;
var latitude2 = 40.40;
var longitude2 = -3.68;

var distance = google.maps.geometry.spherical.computeDistanceBetween(new google.maps.LatLng(latitude1, longitude1), new google.maps.LatLng(latitude2, longitude2));       

如果你想自己计算，那么你可以使用哈弗辛公式:

var rad = function(x) {
  return x * Math.PI / 180;
};

var getDistance = function(p1, p2) {
  var R = 6378137; // Earth’s mean radius in meter
  var dLat = rad(p2.lat() - p1.lat());
  var dLong = rad(p2.lng() - p1.lng());
  var a = Math.sin(dLat / 2) * Math.sin(dLat / 2) +
    Math.cos(rad(p1.lat())) * Math.cos(rad(p2.lat())) *
    Math.sin(dLong / 2) * Math.sin(dLong / 2);
  var c = 2 * Math.atan2(Math.sqrt(a), Math.sqrt(1 - a));
  var d = R * c;
  return d; // returns the distance in meter
};

在我的情况下，这是最好的计算在SQL Server，因为我想采取当前位置，然后搜索所有邮政编码从当前位置一定距离内。我还有一个数据库，其中包含邮政编码及其纬度的列表。干杯

--will return the radius for a given number
create function getRad(@variable float)--function to return rad
returns float
as
begin
declare @retval float 
select @retval=(@variable * PI()/180)
--print @retval
return @retval
end
go

--calc distance
--drop function dbo.getDistance
create function getDistance(@cLat float,@cLong float, @tLat float, @tLong float)
returns float
as
begin
declare @emr float
declare @dLat float
declare @dLong float
declare @a float
declare @distance float
declare @c float

set @emr = 6371--earth mean 
set @dLat = dbo.getRad(@tLat - @cLat);
set @dLong = dbo.getRad(@tLong - @cLong);
set @a = sin(@dLat/2)*sin(@dLat/2)+cos(dbo.getRad(@cLat))*cos(dbo.getRad(@tLat))*sin(@dLong/2)*sin(@dLong/2);
set @c = 2*atn2(sqrt(@a),sqrt(1-@a))
set @distance = @emr*@c;
set @distance = @distance * 0.621371 -- i needed it in miles
--print @distance
return @distance;
end 
go


--get all zipcodes within 2 miles, the hardcoded #'s would be passed in by C#
select *
from cityzips a where dbo.getDistance(29.76,-95.38,a.lat,a.long) <3
order by zipcode

在PHP中，使用谷歌映射距离矩阵API:

//Get the Driving(Mode) distance between two Geo-location points(Latitude, Longitude) pair.
function get_distance($lat1, $lat2, $long1, $long2)
{
    $url = "https://maps.googleapis.com/maps/api/distancematrix/json?origins=".$lat1.",".$long1."&destinations=".$lat2.",".$long2."&mode=driving"."&units=imperial";
    //You can request distance data for different travel modes, request distance data in different units such as kilometers or miles, and estimate travel time in traffic.
    try{
        $ch = curl_init();
        curl_setopt($ch, CURLOPT_URL, $url);
        curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
        curl_setopt($ch, CURLOPT_PROXYPORT, 3128);
        curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, 0);
        curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, 0);
        $response = curl_exec($ch);
        curl_close($ch);
        $response_a = json_decode($response, true);
        //Invalid request OR Empty response
        if(isset($response_a['error_message']) || empty($response_a['rows'])) 
            throw new Exception($response_a['error_message']);
        
    } catch(Exception $e){
        //Handle error here.
        return [];
    }
    
    //The unit parameter in the request URL only affects the text displayed within distance fields. The distance fields in response also contain values that are always expressed in meters.
    $dist = $response_a['rows'][0]['elements'][0]['distance']['text'];
    $time = $response_a['rows'][0]['elements'][0]['duration']['text'];

    return ['distance' => $dist, 'time' => $time];
}

参考:距离矩阵API请求和响应

使用谷歌距离矩阵服务非常简单

第一步是从谷歌API控制台激活距离矩阵服务。 它返回一组位置之间的距离。 应用这个简单的函数

function initMap() {
        var bounds = new google.maps.LatLngBounds;
        var markersArray = [];

        var origin1 = {lat:23.0203, lng: 72.5562};
        //var origin2 = 'Ahmedabad, India';
        var destinationA = {lat:23.0436503, lng: 72.55008939999993};
        //var destinationB = {lat: 23.2156, lng: 72.6369};

        var destinationIcon = 'https://chart.googleapis.com/chart?' +
            'chst=d_map_pin_letter&chld=D|FF0000|000000';
        var originIcon = 'https://chart.googleapis.com/chart?' +
            'chst=d_map_pin_letter&chld=O|FFFF00|000000';
        var map = new google.maps.Map(document.getElementById('map'), {
          center: {lat: 55.53, lng: 9.4},
          zoom: 10
        });
        var geocoder = new google.maps.Geocoder;

        var service = new google.maps.DistanceMatrixService;
        service.getDistanceMatrix({
          origins: [origin1],
          destinations: [destinationA],
          travelMode: 'DRIVING',
          unitSystem: google.maps.UnitSystem.METRIC,
          avoidHighways: false,
          avoidTolls: false
        }, function(response, status) {
          if (status !== 'OK') {
            alert('Error was: ' + status);
          } else {
            var originList = response.originAddresses;
            var destinationList = response.destinationAddresses;
            var outputDiv = document.getElementById('output');
            outputDiv.innerHTML = '';
            deleteMarkers(markersArray);

            var showGeocodedAddressOnMap = function(asDestination) {
              var icon = asDestination ? destinationIcon : originIcon;
              return function(results, status) {
                if (status === 'OK') {
                  map.fitBounds(bounds.extend(results[0].geometry.location));
                  markersArray.push(new google.maps.Marker({
                    map: map,
                    position: results[0].geometry.location,
                    icon: icon
                  }));
                } else {
                  alert('Geocode was not successful due to: ' + status);
                }
              };
            };

            for (var i = 0; i < originList.length; i++) {
              var results = response.rows[i].elements;
              geocoder.geocode({'address': originList[i]},
                  showGeocodedAddressOnMap(false));
              for (var j = 0; j < results.length; j++) {
                geocoder.geocode({'address': destinationList[j]},
                    showGeocodedAddressOnMap(true));
                //outputDiv.innerHTML += originList[i] + ' to ' + destinationList[j] + ': ' + results[j].distance.text + ' in ' +                    results[j].duration.text + '<br>';
                outputDiv.innerHTML += results[j].distance.text + '<br>';
              }
            }

          }
        });
      }

其中origin1是你的位置，destinationA是目的地位置。您可以添加以上两个或多个数据。

Rad完整文档与示例