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
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
// 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
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;
}
c
?c
是用来做什么的? - Jeongbebs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。
Location
对象。 - Fr4nz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+'
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。
@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;
}
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);
}
}
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);
}
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;
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。