使用Google Map API V2查找地图上两点之间的距离

75

我正在我的安卓应用程序中使用谷歌地图API v2,我能够显示地图并在上面放置标记,但现在我遇到了一个问题,需要找出放置在地图上的两个标记或点之间的距离,我已经查看了文档,但在这种情况下没有找到任何有用的信息。

如果有人知道如何解决这个问题,请帮助我。

谢谢


这里可能存在一个误解,你应该重新检查距离和位移之间的差异。据我所知,Google地图API只提供两点之间的位移而不是距离,你可能需要自己处理或计算距离。 - Bitwise DEVS
16个回答

90
在 Google Map API V2 中,您可以使用 LatLng 对象,因此您无法使用 distanceTo(但目前还没有支持)。您可以按照以下代码考虑 oldPosition 和 newPosition 是 LatLng 对象:
// The computed distance is stored in results[0].
//If results has length 2 or greater, the initial bearing is stored in results[1].
//If results has length 3 or greater, the final bearing is stored in results[2].
float[] results = new float[1];
Location.distanceBetween(oldPosition.latitude, oldPosition.longitude,
                newPosition.latitude, newPosition.longitude, results);

要了解有关Location类的更多信息,请参阅此链接


79
您可以使用以下方法,这将为您提供准确的结果。
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;
    }

1
为什么要将它乘以 cc 是用来做什么的? - Jeongbebs
3
不是最佳实践...你应该使用这个链接:https://dev59.com/nWYq5IYBdhLWcg3wjBMM#15351351 的位置。 - hanoo
1
似乎对于普通程序员来说,这是一个复杂的解决方案,他们难以独自想出。 - Harsha
1
不再使用此内容。请使用https://developers.google.com/maps/documentation/android-sdk/utility/。 - Martin Marconcini

68

您应该使用安卓位置定位功能

您可以执行以下操作:

location1.distanceTo(location2);

还有:

float[] results = new float[1];
Location.distanceBetween(latLongA.latitude, latLongA.longitude,
                         latLongB.latitude, latLongB.longitude,
                         results);

使用location,你将得到位置1和位置2之间的距离(以米为单位),以及经纬度A和经纬度B之间的距离。


1
你不能这样做,因为在Google API V2中没有 Location 对象。 - Fr4nz
1
这绝对是最简单的方法!还可以查看我的答案,了解当前位置和标记之间的距离。 - Mohammed Ali
Location.distanceBetween是一个void方法,你怎么从void方法中获取结果? - Karue Benson Karue
2
@SagarHudge 你是认真的吗?1公里等于1000米...只需要使用数学函数即可。 - PanCrucian
3
它提供的结果不够准确。如果有人需要两点之间实际路线距离,而不仅仅是直线距离,怎么办? - Sadda Hussain
显示剩余2条评论

48

虽然来得有些晚,但既然这是谷歌搜索结果中该主题的热门结果之一,我将分享另一种方法:

使用谷歌的实用工具类SphericalUtil来编写一行代码。

SphericalUtil.computeDistanceBetween(latLngFrom, latLngTo)
您需要使用实用类

您可以使用gradle轻松将它们包含在项目中:

implementation 'com.google.maps.android:android-maps-utils:0.5+'

谢谢分享这个... 用SphericalUtil有没有办法找出两点之间的时间? - Sophie
此方法不再适用,因为依赖项已被移除。 - Sadda Hussain
2
我刚刚检查了一下,对我来说运行得很好。我已经更新到0.5版本,但0.4版本也可以工作。请参阅文档:https://developers.google.com/maps/documentation/android-sdk/utility/setup - Björn Kechel
它能用,但与谷歌方向API相比,它提供的距离不准确,少了1或2公里。 - Ashwin H
@AshwinH 这并不是计算街道方向,而是直线距离,两者非常不同。因此,如果您想知道需要旅行多远,请不要使用此功能,您需要使用方向指引。 - Björn Kechel

17

所有这些答案都将给出直线距离。如果您需要获得道路距离,则必须解析Google在调用其服务后发送回来的JSON。您可以使用以下方法:

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;
}

lat1和lon1是起点坐标,lat2和lon2是目的地坐标。


我认为这是地球陆地的正确答案,因为距离是通过道路测量而不是直线测量的,谢谢。 - bebosh
"error_message": "您必须在Google Cloud项目上启用计费..." - Rohaitas Tanoli
使用AsyncTask在性能方面更好。 - Eng.OsamaYousef

13

@salman khan,Usman Kurd提出的建议非常完美。唯一需要纠正的是,“对于Google Maps v2,我们使用< strong>LatLng类”,以下是Usman Kurd提供的适用于Google Maps v2的代码,我已经检查过,它运行得非常好。

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;
     }

4
C是光速,它是物理学中的一个常数。在某些公式中,我们需要将其他物理量乘以C来得到正确的单位或维度。这种做法可以确保我们对于速度、能量和质量等物理量的测量是准确的。因此乘以C是为了使计算结果更加精确和准确。 - Jongz Puangput

6
public class GoogleDirection {

    public final static String MODE_DRIVING = "driving";
    public final static String MODE_WALKING = "walking";
    public final static String MODE_BICYCLING = "bicycling";

    public final static String STATUS_OK = "OK";
    public final static String STATUS_NOT_FOUND = "NOT_FOUND";
    public final static String STATUS_ZERO_RESULTS = "ZERO_RESULTS";
    public final static String STATUS_MAX_WAYPOINTS_EXCEEDED = "MAX_WAYPOINTS_EXCEEDED";
    public final static String STATUS_INVALID_REQUEST = "INVALID_REQUEST";
    public final static String STATUS_OVER_QUERY_LIMIT = "OVER_QUERY_LIMIT";
    public final static String STATUS_REQUEST_DENIED = "REQUEST_DENIED";
    public final static String STATUS_UNKNOWN_ERROR = "UNKNOWN_ERROR";

    public final static int SPEED_VERY_FAST = 1;
    public final static int SPEED_FAST = 2;
    public final static int SPEED_NORMAL = 3;
    public final static int SPEED_SLOW = 4;
    public final static int SPEED_VERY_SLOW = 5;

    private OnDirectionResponseListener mDirectionListener = null;
    private OnAnimateListener mAnimateListener = null;

    private boolean isLogging = false;

    private LatLng animateMarkerPosition = null;
    private LatLng beginPosition = null;
    private LatLng endPosition = null;
    private ArrayList<LatLng> animatePositionList = null;
    private Marker animateMarker = null;
    private Polyline animateLine = null;
    private GoogleMap gm = null;
    private int step = -1;
    private int animateSpeed = -1;
    private int zoom = -1;
    private double animateDistance = -1;
    private double animateCamera = -1;
    private double totalAnimateDistance = 0;
    private boolean cameraLock = false;
    private boolean drawMarker = false;
    private boolean drawLine = false;
    private boolean flatMarker = false;
    private boolean isCameraTilt = false;
    private boolean isCameraZoom = false;
    private boolean isAnimated = false;

    private Context mContext = null;

    public GoogleDirection(Context context) { 
        mContext = context;
    }

    public String request(LatLng start, LatLng end, String mode) {
        final String url = "http://maps.googleapis.com/maps/api/directions/xml?"
                + "origin=" + start.latitude + "," + start.longitude  
                + "&destination=" + end.latitude + "," + end.longitude 
                + "&sensor=false&units=metric&mode=" + mode;

        if(isLogging)
            Log.i("GoogleDirection", "URL : " + url);
        new RequestTask().execute(new String[]{ url });
        return url;
    }

    private class RequestTask extends AsyncTask<String, Void, Document> {
        protected Document doInBackground(String... url) {
            try {
                HttpClient httpClient = new DefaultHttpClient();
                HttpContext localContext = new BasicHttpContext();
                HttpPost httpPost = new HttpPost(url[0]);
                HttpResponse response = httpClient.execute(httpPost, localContext);
                InputStream in = response.getEntity().getContent();
                DocumentBuilder builder = DocumentBuilderFactory.newInstance().newDocumentBuilder();
                return builder.parse(in);
            } catch (IOException e) {
                e.printStackTrace();
            } catch (ParserConfigurationException e) {
                e.printStackTrace();
            } catch (SAXException e) {
                e.printStackTrace();
            } 
            return null;
        }

        protected void onPostExecute(Document doc) {
            super.onPostExecute(doc);
            if(mDirectionListener != null)
                mDirectionListener.onResponse(getStatus(doc), doc, GoogleDirection.this);
        }

        private String getStatus(Document doc) {
            NodeList nl1 = doc.getElementsByTagName("status");
            Node node1 = nl1.item(0);
            if(isLogging)
                Log.i("GoogleDirection", "Status : " + node1.getTextContent());
            return node1.getTextContent();
        }
    }

    public void setLogging(boolean state) {
        isLogging = state;
    }

    public String getStatus(Document doc) {
        NodeList nl1 = doc.getElementsByTagName("status");
        Node node1 = nl1.item(0);
        if(isLogging)
            Log.i("GoogleDirection", "Status : " + node1.getTextContent());
        return node1.getTextContent();
    }

    public String[] getDurationText(Document doc) {
        NodeList nl1 = doc.getElementsByTagName("duration");
        String[] arr_str = new String[nl1.getLength() - 1];
        for(int i = 0 ; i < nl1.getLength() - 1 ; i++) {
            Node node1 = nl1.item(i);
            NodeList nl2 = node1.getChildNodes();
            Node node2 = nl2.item(getNodeIndex(nl2, "text"));
            arr_str[i] = node2.getTextContent();
            if(isLogging)
                Log.i("GoogleDirection", "DurationText : " + node2.getTextContent());
        }
        return arr_str;
    }

    public int[] getDurationValue(Document doc) {
        NodeList nl1 = doc.getElementsByTagName("duration");
        int[] arr_int = new int[nl1.getLength() - 1];
        for(int i = 0 ; i < nl1.getLength() - 1 ; i++) {
            Node node1 = nl1.item(i);
            NodeList nl2 = node1.getChildNodes();
            Node node2 = nl2.item(getNodeIndex(nl2, "value"));
            arr_int[i] = Integer.parseInt(node2.getTextContent());
            if(isLogging)
                Log.i("GoogleDirection", "Duration : " + node2.getTextContent());
        }
        return arr_int;
    }

    public String getTotalDurationText(Document doc) {
        NodeList nl1 = doc.getElementsByTagName("duration");
        Node node1 = nl1.item(nl1.getLength() - 1);
        NodeList nl2 = node1.getChildNodes();
        Node node2 = nl2.item(getNodeIndex(nl2, "text"));
        if(isLogging)
            Log.i("GoogleDirection", "TotalDuration : " + node2.getTextContent());
        return node2.getTextContent();
    }

    public int getTotalDurationValue(Document doc) {
        NodeList nl1 = doc.getElementsByTagName("duration");
        Node node1 = nl1.item(nl1.getLength() - 1);
        NodeList nl2 = node1.getChildNodes();
        Node node2 = nl2.item(getNodeIndex(nl2, "value"));
        if(isLogging)
            Log.i("GoogleDirection", "TotalDuration : " + node2.getTextContent());
        return Integer.parseInt(node2.getTextContent());
    }

    public String[] getDistanceText(Document doc) {
        NodeList nl1 = doc.getElementsByTagName("distance");
        String[] arr_str = new String[nl1.getLength() - 1];
        for(int i = 0 ; i < nl1.getLength() - 1 ; i++) {
            Node node1 = nl1.item(i);
            NodeList nl2 = node1.getChildNodes();
            Node node2 = nl2.item(getNodeIndex(nl2, "text"));
            arr_str[i] = node2.getTextContent();
            if(isLogging)
                Log.i("GoogleDirection", "DurationText : " + node2.getTextContent());
        }
        return arr_str;
    }

    public int[] getDistanceValue(Document doc) {
        NodeList nl1 = doc.getElementsByTagName("distance");
        int[] arr_int = new int[nl1.getLength() - 1];
        for(int i = 0 ; i < nl1.getLength() - 1 ; i++) {
            Node node1 = nl1.item(i);
            NodeList nl2 = node1.getChildNodes();
            Node node2 = nl2.item(getNodeIndex(nl2, "value"));
            arr_int[i] = Integer.parseInt(node2.getTextContent());
            if(isLogging)
                Log.i("GoogleDirection", "Duration : " + node2.getTextContent());
        }
        return arr_int;
    }

    public String getTotalDistanceText(Document doc) {
        NodeList nl1 = doc.getElementsByTagName("distance");
        Node node1 = nl1.item(nl1.getLength() - 1);
        NodeList nl2 = node1.getChildNodes();
        Node node2 = nl2.item(getNodeIndex(nl2, "text"));
        if(isLogging)
            Log.i("GoogleDirection", "TotalDuration : " + node2.getTextContent());
        return node2.getTextContent();
    }

    public int getTotalDistanceValue(Document doc) {
        NodeList nl1 = doc.getElementsByTagName("distance");
        Node node1 = nl1.item(nl1.getLength() - 1);
        NodeList nl2 = node1.getChildNodes();
        Node node2 = nl2.item(getNodeIndex(nl2, "value"));
        if(isLogging)
            Log.i("GoogleDirection", "TotalDuration : " + node2.getTextContent());
        return Integer.parseInt(node2.getTextContent());
    }

    public String getStartAddress(Document doc) {
        NodeList nl1 = doc.getElementsByTagName("start_address");
        Node node1 = nl1.item(0);
        if(isLogging)
            Log.i("GoogleDirection", "StartAddress : " + node1.getTextContent());
        return node1.getTextContent();
    }

    public String getEndAddress(Document doc) {
        NodeList nl1 = doc.getElementsByTagName("end_address");
        Node node1 = nl1.item(0);
        if(isLogging)
            Log.i("GoogleDirection", "StartAddress : " + node1.getTextContent());
        return node1.getTextContent();
    }

    public String getCopyRights(Document doc) {
        NodeList nl1 = doc.getElementsByTagName("copyrights");
        Node node1 = nl1.item(0);
        if(isLogging)
            Log.i("GoogleDirection", "CopyRights : " + node1.getTextContent());
        return node1.getTextContent();
    }

    public ArrayList<LatLng> getDirection(Document doc) {
        NodeList nl1, nl2, nl3;
        ArrayList<LatLng> listGeopoints = new ArrayList<LatLng>();
        nl1 = doc.getElementsByTagName("step");
        if (nl1.getLength() > 0) {
            for (int i = 0; i < nl1.getLength(); i++) {
                Node node1 = nl1.item(i);
                nl2 = node1.getChildNodes();

                Node locationNode = nl2.item(getNodeIndex(nl2, "start_location"));
                nl3 = locationNode.getChildNodes();
                Node latNode = nl3.item(getNodeIndex(nl3, "lat"));
                double lat = Double.parseDouble(latNode.getTextContent());
                Node lngNode = nl3.item(getNodeIndex(nl3, "lng"));
                double lng = Double.parseDouble(lngNode.getTextContent());
                listGeopoints.add(new LatLng(lat, lng));

                locationNode = nl2.item(getNodeIndex(nl2, "polyline"));
                nl3 = locationNode.getChildNodes();
                latNode = nl3.item(getNodeIndex(nl3, "points"));
                ArrayList<LatLng> arr = decodePoly(latNode.getTextContent());
                for(int j = 0 ; j < arr.size() ; j++) {
                    listGeopoints.add(new LatLng(arr.get(j).latitude
                            , arr.get(j).longitude));
                }

                locationNode = nl2.item(getNodeIndex(nl2, "end_location"));
                nl3 = locationNode.getChildNodes();
                latNode = nl3.item(getNodeIndex(nl3, "lat"));
                lat = Double.parseDouble(latNode.getTextContent());
                lngNode = nl3.item(getNodeIndex(nl3, "lng"));
                lng = Double.parseDouble(lngNode.getTextContent());
                listGeopoints.add(new LatLng(lat, lng));
            }
        }

        return listGeopoints;
    }

    public ArrayList<LatLng> getSection(Document doc) {
        NodeList nl1, nl2, nl3;
        ArrayList<LatLng> listGeopoints = new ArrayList<LatLng>();
        nl1 = doc.getElementsByTagName("step");
        if (nl1.getLength() > 0) {
            for (int i = 0; i < nl1.getLength(); i++) {
                Node node1 = nl1.item(i);
                nl2 = node1.getChildNodes();

                Node locationNode = nl2.item(getNodeIndex(nl2, "end_location"));
                nl3 = locationNode.getChildNodes();
                Node latNode = nl3.item(getNodeIndex(nl3, "lat"));
                double lat = Double.parseDouble(latNode.getTextContent());
                Node lngNode = nl3.item(getNodeIndex(nl3, "lng"));
                double lng = Double.parseDouble(lngNode.getTextContent());
                listGeopoints.add(new LatLng(lat, lng));
            }
        }

        return listGeopoints;
    }

    public PolylineOptions getPolyline(Document doc, int width, int color) {
        ArrayList<LatLng> arr_pos = getDirection(doc);
        PolylineOptions rectLine = new PolylineOptions().width(dpToPx(width)).color(color);
        for(int i = 0 ; i < arr_pos.size() ; i++)        
            rectLine.add(arr_pos.get(i));
        return rectLine;
    }

    private int getNodeIndex(NodeList nl, String nodename) {
        for(int i = 0 ; i < nl.getLength() ; i++) {
            if(nl.item(i).getNodeName().equals(nodename))
                return i;
        }
        return -1;
    }

    private ArrayList<LatLng> decodePoly(String encoded) {
        ArrayList<LatLng> poly = new ArrayList<LatLng>();
        int index = 0, len = encoded.length();
        int lat = 0, lng = 0;
        while (index < len) {
            int b, shift = 0, result = 0;
            do {
                b = encoded.charAt(index++) - 63;
                result |= (b & 0x1f) << shift;
                shift += 5;
            } while (b >= 0x20);
            int dlat = ((result & 1) != 0 ? ~(result >> 1) : (result >> 1));
            lat += dlat;
            shift = 0;
            result = 0;
            do {
                b = encoded.charAt(index++) - 63;
                result |= (b & 0x1f) << shift;
                shift += 5;
            } while (b >= 0x20);
            int dlng = ((result & 1) != 0 ? ~(result >> 1) : (result >> 1));
            lng += dlng;

            LatLng position = new LatLng((double)lat / 1E5, (double)lng / 1E5);
            poly.add(position);
        }
        return poly;
    }

    private int dpToPx(int dp) {
        DisplayMetrics displayMetrics = mContext.getResources().getDisplayMetrics();
        int px = Math.round(dp * (displayMetrics.xdpi / DisplayMetrics.DENSITY_DEFAULT));       
        return px;
    }

    public void setOnDirectionResponseListener(OnDirectionResponseListener listener) {
        mDirectionListener = listener;
    }

    public void setOnAnimateListener(OnAnimateListener listener) {
        mAnimateListener = listener;
    }

    public interface OnDirectionResponseListener {
        public void onResponse(String status, Document doc, GoogleDirection gd);
    }

    public interface OnAnimateListener {
        public void onFinish();
        public void onStart();
        public void onProgress(int progress, int total);
    }

    public void animateDirection(GoogleMap gm, ArrayList<LatLng> direction, int speed
            , boolean cameraLock, boolean isCameraTilt, boolean isCameraZoom
            , boolean drawMarker, MarkerOptions mo, boolean flatMarker
            , boolean drawLine, PolylineOptions po) {
        if(direction.size() > 1) {
            isAnimated = true;
            animatePositionList = direction;
            animateSpeed = speed;
            this.drawMarker = drawMarker;
            this.drawLine = drawLine;
            this.flatMarker = flatMarker;
            this.isCameraTilt = isCameraTilt;
            this.isCameraZoom = isCameraZoom;
            step = 0;
            this.cameraLock = cameraLock;
            this.gm = gm;

            setCameraUpdateSpeed(speed);

            beginPosition = animatePositionList.get(step);
            endPosition = animatePositionList.get(step + 1);
            animateMarkerPosition = beginPosition;

            if(mAnimateListener != null)
                mAnimateListener.onProgress(step, animatePositionList.size());

            if(cameraLock) {
                float bearing = getBearing(beginPosition, endPosition);
                CameraPosition.Builder cameraBuilder = new CameraPosition.Builder()
                    .target(animateMarkerPosition).bearing(bearing);

                if(isCameraTilt) 
                    cameraBuilder.tilt(90);
                else 
                    cameraBuilder.tilt(gm.getCameraPosition().tilt);

                if(isCameraZoom) 
                    cameraBuilder.zoom(zoom);
                else 
                    cameraBuilder.zoom(gm.getCameraPosition().zoom);

                CameraPosition cameraPosition = cameraBuilder.build();
                gm.animateCamera(CameraUpdateFactory.newCameraPosition(cameraPosition));
            }

            if(drawMarker) {
                if(mo != null)
                    animateMarker = gm.addMarker(mo.position(beginPosition));
                else 
                    animateMarker = gm.addMarker(new MarkerOptions().position(beginPosition));

                if(flatMarker) {
                    animateMarker.setFlat(true);

                    float rotation = getBearing(animateMarkerPosition, endPosition) + 180;
                    animateMarker.setRotation(rotation);
                }
            }


            if(drawLine) {
                if(po != null) 
                    animateLine = gm.addPolyline(po.add(beginPosition)
                            .add(beginPosition).add(endPosition)
                            .width(dpToPx((int)po.getWidth())));
                else 
                    animateLine = gm.addPolyline(new PolylineOptions()
                            .width(dpToPx(5)));
            }

            new Handler().postDelayed(r, speed);
            if(mAnimateListener != null)
                mAnimateListener.onStart();
        }
    }

    public void cancelAnimated() {
        isAnimated = false;
    }

    public boolean isAnimated() {
        return isAnimated;
    }

    private Runnable r = new Runnable() {
        public void run() {

            animateMarkerPosition = getNewPosition(animateMarkerPosition, endPosition);

            if(drawMarker)
                animateMarker.setPosition(animateMarkerPosition);


            if(drawLine) {
                List<LatLng> points = animateLine.getPoints();
                points.add(animateMarkerPosition);
                animateLine.setPoints(points);
            }

            if((animateMarkerPosition.latitude == endPosition.latitude 
                    && animateMarkerPosition.longitude == endPosition.longitude)) {
                if(step == animatePositionList.size() - 2) {
                    isAnimated = false;
                    totalAnimateDistance = 0;
                    if(mAnimateListener != null)
                        mAnimateListener.onFinish();
                } else {
                    step++;
                    beginPosition = animatePositionList.get(step);
                    endPosition = animatePositionList.get(step + 1);
                    animateMarkerPosition = beginPosition;

                    if(flatMarker && step + 3 < animatePositionList.size() - 1) {
                        float rotation = getBearing(animateMarkerPosition, animatePositionList.get(step + 3)) + 180;
                        animateMarker.setRotation(rotation);
                    }

                    if(mAnimateListener != null)
                        mAnimateListener.onProgress(step, animatePositionList.size());
                }
            }

            if(cameraLock && (totalAnimateDistance > animateCamera || !isAnimated)) {
                totalAnimateDistance = 0;
                float bearing = getBearing(beginPosition, endPosition);
                CameraPosition.Builder cameraBuilder = new CameraPosition.Builder()
                    .target(animateMarkerPosition).bearing(bearing);

                if(isCameraTilt) 
                    cameraBuilder.tilt(90);
                else 
                    cameraBuilder.tilt(gm.getCameraPosition().tilt);

                if(isCameraZoom) 
                    cameraBuilder.zoom(zoom);
                else 
                    cameraBuilder.zoom(gm.getCameraPosition().zoom);

                CameraPosition cameraPosition = cameraBuilder.build();
                gm.animateCamera(CameraUpdateFactory.newCameraPosition(cameraPosition));

            }

            if(isAnimated) {
                new Handler().postDelayed(r, animateSpeed);
            }
        }
    };

    public Marker getAnimateMarker() {
        return animateMarker;
    }

    public Polyline getAnimatePolyline() {
        return animateLine;
    }

    private LatLng getNewPosition(LatLng begin, LatLng end) {
        double lat = Math.abs(begin.latitude - end.latitude); 
        double lng = Math.abs(begin.longitude - end.longitude);

        double dis = Math.sqrt(Math.pow(lat, 2) + Math.pow(lng, 2));
        if(dis >= animateDistance) {
            double angle = -1;

            if(begin.latitude <= end.latitude && begin.longitude <= end.longitude)
                angle = Math.toDegrees(Math.atan(lng / lat));
            else if(begin.latitude > end.latitude && begin.longitude <= end.longitude)
                angle = (90 - Math.toDegrees(Math.atan(lng / lat))) + 90;
            else if(begin.latitude > end.latitude && begin.longitude > end.longitude)
                angle = Math.toDegrees(Math.atan(lng / lat)) + 180;
            else if(begin.latitude <= end.latitude && begin.longitude > end.longitude)
                angle = (90 - Math.toDegrees(Math.atan(lng / lat))) + 270;

            double x = Math.cos(Math.toRadians(angle)) * animateDistance;
            double y = Math.sin(Math.toRadians(angle)) * animateDistance;
            totalAnimateDistance += animateDistance;
            double finalLat = begin.latitude + x;
            double finalLng = begin.longitude + y;

            return new LatLng(finalLat, finalLng);
        } else {
            return end;
        }
    }

    private float getBearing(LatLng begin, LatLng end) {
        double lat = Math.abs(begin.latitude - end.latitude); 
        double lng = Math.abs(begin.longitude - end.longitude);
         if(begin.latitude < end.latitude && begin.longitude < end.longitude)
            return (float)(Math.toDegrees(Math.atan(lng / lat)));
        else if(begin.latitude >= end.latitude && begin.longitude < end.longitude)
            return (float)((90 - Math.toDegrees(Math.atan(lng / lat))) + 90);
        else if(begin.latitude >= end.latitude && begin.longitude >= end.longitude)
            return  (float)(Math.toDegrees(Math.atan(lng / lat)) + 180);
        else if(begin.latitude < end.latitude && begin.longitude >= end.longitude)
            return (float)((90 - Math.toDegrees(Math.atan(lng / lat))) + 270);
         return -1;
    }

    public void setCameraUpdateSpeed(int speed) {       
        if(speed == SPEED_VERY_SLOW) {
            animateDistance = 0.000005;
            animateSpeed = 20;
            animateCamera = 0.0004;
            zoom = 19;
        } else if(speed == SPEED_SLOW) {
            animateDistance = 0.00001;
            animateSpeed = 20;
            animateCamera = 0.0008;
            zoom = 18;
        } else if(speed == SPEED_NORMAL) {
            animateDistance = 0.00005;
            animateSpeed = 20;
            animateCamera = 0.002;
            zoom = 16;
        } else if(speed == SPEED_FAST) {
            animateDistance = 0.0001;
            animateSpeed = 20;
            animateCamera = 0.004;
            zoom = 15;
        } else if(speed == SPEED_VERY_FAST) {
            animateDistance = 0.0005;
            animateSpeed = 20;
            animateCamera = 0.004;
            zoom = 13;
        } else {
            animateDistance = 0.00005;
            animateSpeed = 20;
            animateCamera = 0.002;
            zoom = 16;
        }
    }
}

//主要活动

public class MapActivity extends ActionBarActivity {

    GoogleMap map = null;
    GoogleDirection gd;

    LatLng start,end;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_map);

        start = new LatLng(13.744246499553903, 100.53428772836924);
        end = new LatLng(13.751279688694071, 100.54316081106663);


        map = ((MapFragment) getFragmentManager().findFragmentById(R.id.map)).getMap();
        map.animateCamera(CameraUpdateFactory.newLatLngZoom(start, 15));

        gd = new GoogleDirection(this);
        gd.setOnDirectionResponseListener(new GoogleDirection.OnDirectionResponseListener() {
            public void onResponse(String status, Document doc, GoogleDirection gd) {
                Toast.makeText(getApplicationContext(), status, Toast.LENGTH_SHORT).show();

                gd.animateDirection(map, gd.getDirection(doc), GoogleDirection.SPEED_FAST
                        , true, true, true, false, null, false, true, new PolylineOptions().width(8).color(Color.RED));

                map.addMarker(new MarkerOptions().position(start)
                        .icon(BitmapDescriptorFactory.fromResource(R.drawable.markera)));

                map.addMarker(new MarkerOptions().position(end)
                        .icon(BitmapDescriptorFactory.fromResource(R.drawable.markerb)));

                String TotalDistance = gd.getTotalDistanceText(doc);
                String TotalDuration = gd.getTotalDurationText(doc);
            }
        });

        gd.request(start, end, GoogleDirection.MODE_DRIVING);
    }
}

6

一个简单的工具函数,用于计算两个地理坐标点之间的距离:

public static long getDistanceMeters(double lat1, double lng1, double lat2, double lng2) {

    double l1 = toRadians(lat1);
    double l2 = toRadians(lat2);
    double g1 = toRadians(lng1);
    double g2 = toRadians(lng2);

    double dist = acos(sin(l1) * sin(l2) + cos(l1) * cos(l2) * cos(g1 - g2));
    if(dist < 0) {
        dist = dist + Math.PI;
    }

    return Math.round(dist * 6378100);
}

为什么要用 PI 来增加距离? - rtsketo

6

试试这个

double distance;
Location locationA = new Location("");
locationA.setLatitude(main_Latitude);
locationA.setLongitude(main_Longitude);
Location locationB = new Location("");
locationB.setLatitude(sub_Latitude);
locationB.setLongitude(sub_Longitude);
distance = locationA.distanceTo(locationB)/1000;
kmeter.setText(String.valueOf(distance));
Toast.makeText(getApplicationContext(), ""+distance, Toast.LENGTH_LONG).show();double distance;

4

通过使用Haversine公式,可以找到两个地理坐标之间的距离。该公式适用于计算球体(如我们所在的地球)上的距离。


1
事实上,地球不是球形的,而是椭圆形的。谷歌使用墨卡托投影! - Driss Bounouar
这个回答与问题无关。此外,最好在此处包含链接答案的基本部分,并提供参考链接。如果链接页面更改,仅链接的答案可能会失效。 - David

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