标记似乎没有从谷歌地图中选择和定位计算和绘制两个标记之间的路径。
我想用标记选择两个位置并计算距离并在选择后在两个标记之间绘制一条路径。但是无法用标记选择两个位置而无法计算距离。
我无法使用标记设置位置，使用标记设置为位置，也无法计算距离。
MapsActivity.java
public class MapsActivity extends FragmentActivity implements
OnMapReadyCallback,
GoogleApiClient.ConnectionCallbacks,
GoogleApiClient.OnConnectionFailedListener,
GoogleMap.OnMarkerDragListener,
GoogleMap.OnMapLongClickListener,
View.OnClickListener{
//Our Map
private GoogleMap mMap;
//To store longitude and latitude from map
private double longitude;
private double latitude;
//From -> the first coordinate from where we need to calculate the distance
private double fromLongitude;
private double fromLatitude;
//To -> the second coordinate to where we need to calculate the distance
private double toLongitude;
private double toLatitude;
//Google ApiClient
private GoogleApiClient googleApiClient;
//Our buttons
private Button buttonSetTo;
private Button buttonSetFrom;
private Button buttonCalcDistance;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_maps);
// Obtain the SupportMapFragment and get notified when the map is ready to be used.
SupportMapFragment mapFragment = (SupportMapFragment) getSupportFragmentManager()
.findFragmentById(R.id.map);
mapFragment.getMapAsync(this);
//Initializing googleapi client
// ATTENTION: This "addApi(AppIndex.API)"was auto-generated to implement the App Indexing API.
// See https://g.co/AppIndexing/AndroidStudio for more information.
googleApiClient = new GoogleApiClient.Builder(this)
.addConnectionCallbacks(this)
.addOnConnectionFailedListener(this)
.addApi(LocationServices.API)
.addApi(AppIndex.API).build();
buttonSetTo = (Button) findViewById(R.id.buttonSetTo);
buttonSetFrom = (Button) findViewById(R.id.buttonSetFrom);
buttonCalcDistance = (Button) findViewById(R.id.buttonCalcDistance);
buttonSetTo.setOnClickListener(this);
buttonSetFrom.setOnClickListener(this);
buttonCalcDistance.setOnClickListener(this);
}
@Override
protected void onStart() {
googleApiClient.connect();
super.onStart();
// ATTENTION: This was auto-generated to implement the App Indexing API.
// See https://g.co/AppIndexing/AndroidStudio for more information.
Action viewAction = Action.newAction(
Action.TYPE_VIEW, // TODO: choose an action type.
"Maps Page", // TODO: Define a title for the content shown.
// TODO: If you have web page content that matches this app activity's content,
// make sure this auto-generated web page URL is correct.
// Otherwise, set the URL to null.
Uri.parse("http://host/path"),
// TODO: Make sure this auto-generated app deep link URI is correct.
Uri.parse("android-app://net.simplifiedcoding.googlemapsdistancecalc/http/host/path")
);
AppIndex.AppIndexApi.start(googleApiClient, viewAction);
}
@Override
protected void onStop() {
googleApiClient.disconnect();
super.onStop();
// ATTENTION: This was auto-generated to implement the App Indexing API.
// See https://g.co/AppIndexing/AndroidStudio for more information.
Action viewAction = Action.newAction(
Action.TYPE_VIEW, // TODO: choose an action type.
"Maps Page", // TODO: Define a title for the content shown.
// TODO: If you have web page content that matches this app activity's content,
// make sure this auto-generated web page URL is correct.
// Otherwise, set the URL to null.
Uri.parse("http://host/path"),
// TODO: Make sure this auto-generated app deep link URI is correct.
Uri.parse("android-app://net.simplifiedcoding.googlemapsdistancecalc/http/host/path")
);
AppIndex.AppIndexApi.end(googleApiClient, viewAction);
}
//Getting current location
private void getCurrentLocation() {
mMap.clear();
//Creating a location object
Location location = LocationServices.FusedLocationApi.getLastLocation(googleApiClient);
if (location != null) {
//Getting longitude and latitude
longitude = location.getLongitude();
latitude = location.getLatitude();
//moving the map to location
moveMap();
}
}
//Function to move the map
private void moveMap() {
//Creating a LatLng Object to store Coordinates
LatLng latLng = new LatLng(latitude, longitude);
//Adding marker to map
mMap.addMarker(new MarkerOptions()
.position(latLng) //setting position
.draggable(true) //Making the marker draggable
.title("Current Location")); //Adding a title
//Moving the camera
mMap.moveCamera(CameraUpdateFactory.newLatLng(latLng));
//Animating the camera
mMap.animateCamera(CameraUpdateFactory.zoomTo(15));
}
public String makeURL (double sourcelat, double sourcelog, double destlat, double destlog ){
StringBuilder urlString = new StringBuilder();
urlString.append("https://maps.googleapis.com/maps/api/directions/json");
urlString.append("?origin=");// from
urlString.append(Double.toString(sourcelat));
urlString.append(",");
urlString
.append(Double.toString( sourcelog));
urlString.append("&destination=");// to
urlString
.append(Double.toString( destlat));
urlString.append(",");
urlString.append(Double.toString(destlog));
urlString.append("&sensor=false&mode=driving&alternatives=true");
urlString.append("&key=AIzaSyB2iWnsp0TvWCrBB5AYYxG8J3Mad4q1npo");
return urlString.toString();
}
private void getDirection(){
//Getting the URL
String url = makeURL(fromLatitude, fromLongitude, toLatitude, toLongitude);
//Showing a dialog till we get the route
final ProgressDialog loading = ProgressDialog.show(this, "Getting Route", "Please wait...", false, false);
//Creating a string request
StringRequest stringRequest = new StringRequest(url,
new Response.Listener<String>() {
@Override
public void onResponse(String response) {
loading.dismiss();
//Calling the method drawPath to draw the path
drawPath(response);
}
},
new Response.ErrorListener() {
@Override
public void onErrorResponse(VolleyError error) {
loading.dismiss();
}
});
//Adding the request to request queue
RequestQueue requestQueue = Volley.newRequestQueue(this);
requestQueue.add(stringRequest);
}
//The parameter is the server response
public void drawPath(String result) {
//Getting both the coordinates
LatLng from = new LatLng(fromLatitude,fromLongitude);
LatLng to = new LatLng(toLatitude,toLongitude);
//Calculating the distance in meters
Double distance = SphericalUtil.computeDistanceBetween(from, to);
//Displaying the distance
Toast.makeText(this,String.valueOf(distance+" Meters"),Toast.LENGTH_SHORT).show();
try {
//Parsing json
final JSONObject json = new JSONObject(result);
JSONArray routeArray = json.getJSONArray("routes");
JSONObject routes = routeArray.getJSONObject(0);
JSONObject overviewPolylines = routes.getJSONObject("overview_polyline");
String encodedString = overviewPolylines.getString("points");
List<LatLng> list = decodePoly(encodedString);
Polyline line = mMap.addPolyline(new PolylineOptions()
.addAll(list)
.width(20)
.color(Color.RED)
.geodesic(true)
);
}
catch (JSONException e) {
}
}
private List<LatLng> decodePoly(String encoded) {
List<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 p = new LatLng( (((double) lat / 1E5)),
(((double) lng / 1E5) ));
poly.add(p);
}
return poly;
}
@Override
public void onMapReady(GoogleMap googleMap) {
mMap = googleMap;
LatLng latLng = new LatLng(-34, 151);
mMap.addMarker(new MarkerOptions().position(latLng).draggable(true));
mMap.moveCamera(CameraUpdateFactory.newLatLng(latLng));
mMap.setOnMarkerDragListener(this);
mMap.setOnMapLongClickListener(this);
}
@Override
public void onConnected(Bundle bundle) {
getCurrentLocation();
}
@Override
public void onConnectionSuspended(int i) {
}
@Override
public void onConnectionFailed(ConnectionResult connectionResult) {
}
@Override
public void onMapLongClick(LatLng latLng) {
//Clearing all the markers
mMap.clear();
//Adding a new marker to the current pressed position
mMap.addMarker(new MarkerOptions()
.position(latLng)
.draggable(true));
latitude = latLng.latitude;
longitude = latLng.longitude;
}
@Override
public void onMarkerDragStart(Marker marker) {
}
@Override
public void onMarkerDrag(Marker marker) {
}
@Override
public void onMarkerDragEnd(Marker marker) {
//Getting the coordinates
latitude = marker.getPosition().latitude;
longitude = marker.getPosition().longitude;
//Moving the map
moveMap();
}
@Override
public void onClick(View v) {
if(v == buttonSetFrom){
fromLatitude = latitude;
fromLongitude = longitude;
Toast.makeText(this,"From set",Toast.LENGTH_SHORT).show();
}
if(v == buttonSetTo){
toLatitude = latitude;
toLongitude = longitude;
Toast.makeText(this,"To set",Toast.LENGTH_SHORT).show();
}
if(v == buttonCalcDistance){
getDirection();
}
}
}
activity_maps.xml
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".MapsActivity">
<fragment xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:map="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/map"
android:name="com.google.android.gms.maps.SupportMapFragment"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context="net.simplifiedcoding.mymapapp.MapsActivity" />
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:gravity="bottom"
android:orientation="vertical">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="#cc3b60a7"
android:orientation="horizontal">
<Button
android:id="@+id/buttonSetFrom"
android:text="Set From"
android:layout_width="wrap_content"
android:layout_height="wrap_content" />
<Button
android:id="@+id/buttonSetTo"
android:text="Set To"
android:layout_width="wrap_content"
android:layout_height="wrap_content" />
<Button
android:id="@+id/buttonCalcDistance"
android:text="Calc Distance"
android:layout_width="wrap_content"
android:layout_height="wrap_content" />
</LinearLayout>
</LinearLayout>
</FrameLayout>
答案 0 :(得分：1)
尝试使用此代码绘制两个origin和dest之间的绘制线：
@Override
public void onMapReady(GoogleMap googleMap) {
mMap = googleMap;
// Add a marker in Sydney and move the camera
LatLng sydney = new LatLng(latitude, longitude);
mMap.clear();
CameraUpdate cameraUpdate = CameraUpdateFactory.newLatLngZoom(new LatLng(latitude, longitude), 16);
mMap.animateCamera(cameraUpdate);
System.out.println("Latitude "+latitude+ " \n Longitude "+longitude);
mMap.setMyLocationEnabled(true);
LatLng origin = new LatLng(latitude,longitude);
LatLng dest = new LatLng(Double.parseDouble(destLatitude),Double.parseDouble(destLongitude));
// Getting URL to the Google Directions API
String url = getDirectionsUrl(origin, dest);
DownloadTask downloadTask = new DownloadTask();
// Start downloading json data from Google Directions API
downloadTask.execute(url);
}
private String getDirectionsUrl(LatLng origin,LatLng dest){
// Origin of route
String str_origin = "origin="+origin.latitude+","+origin.longitude;
// Destination of route
String str_dest = "destination="+dest.latitude+","+dest.longitude;
// Sensor enabled
String sensor = "sensor=false";
// Building the parameters to the web service
String parameters = str_origin+"&"+str_dest+"&"+sensor;
// Output format
String output = "json";
// Building the url to the web service
String url = "https://maps.googleapis.com/maps/api/directions/"+output+"?"+parameters;
return url;
}
/** A method to download json data from url */
private String downloadUrl(String strUrl) throws IOException{
String data = "";
InputStream iStream = null;
HttpURLConnection urlConnection = null;
try{
URL url = new URL(strUrl);
// Creating an http connection to communicate with url
urlConnection = (HttpURLConnection) url.openConnection();
// Connecting to url
urlConnection.connect();
// Reading data from url
iStream = urlConnection.getInputStream();
BufferedReader br = new BufferedReader(new InputStreamReader(iStream));
StringBuffer sb = new StringBuffer();
String line = "";
while( ( line = br.readLine()) != null){
sb.append(line);
}
data = sb.toString();
br.close();
}catch(Exception e){
Log.d("Exception downloading", e.toString());
}finally{
iStream.close();
urlConnection.disconnect();
}
return data;
}
// Fetches data from url passed
private class DownloadTask extends AsyncTask<String, Void, String>{
// Downloading data in non-ui thread
@Override
protected String doInBackground(String... url) {
// For storing data from web service
String data = "";
try{
// Fetching the data from web service
data = downloadUrl(url[0]);
}catch(Exception e){
Log.d("Background Task",e.toString());
}
return data;
}
// Executes in UI thread, after the execution of
// doInBackground()
@Override
protected void onPostExecute(String result) {
super.onPostExecute(result);
ParserTask parserTask = new ParserTask();
// Invokes the thread for parsing the JSON data
parserTask.execute(result);
}
}
/** A class to parse the Google Places in JSON format */
private class ParserTask extends AsyncTask<String, Integer, List<List<HashMap<String,String>>> >{
// Parsing the data in non-ui thread
@Override
protected List<List<HashMap<String, String>>> doInBackground(String... jsonData) {
JSONObject jObject;
List<List<HashMap<String, String>>> routes = null;
try{
jObject = new JSONObject(jsonData[0]);
DirectionsJSONParser parser = new DirectionsJSONParser();
// Starts parsing data
routes = parser.parse(jObject);
}catch(Exception e){
e.printStackTrace();
}
return routes;
}
// Executes in UI thread, after the parsing process
@Override
protected void onPostExecute(List<List<HashMap<String, String>>> result) {
ArrayList<LatLng> points = null;
PolylineOptions lineOptions = null;
MarkerOptions markerOptions = new MarkerOptions();
String distance = "";
String duration = "";
if(result.size()<1){
Toast.makeText(getBaseContext(), "No Points", Toast.LENGTH_SHORT).show();
return;
}
// Traversing through all the routes
for(int i=0;i<result.size();i++){
points = new ArrayList<LatLng>();
lineOptions = new PolylineOptions();
// Fetching i-th route
List<HashMap<String, String>> path = result.get(i);
// Fetching all the points in i-th route
for(int j=0;j<path.size();j++){
HashMap<String,String> point = path.get(j);
if(j==0){ // Get distance from the list
distance = (String)point.get("distance");
continue;
}else if(j==1){ // Get duration from the list
duration = (String)point.get("duration");
continue;
}
double lat = Double.parseDouble(point.get("lat"));
double lng = Double.parseDouble(point.get("lng"));
LatLng position = new LatLng(lat, lng);
points.add(position);
}
// Adding all the points in the route to LineOptions
lineOptions.addAll(points);
lineOptions.width(5);
lineOptions.color(Color.RED);
}
tvDistanceDuration.setText("Distance:"+distance + ", Duration:"+duration);
// Drawing polyline in the Google Map for the i-th route
mMap.addPolyline(lineOptions);
mMap.addMarker(new MarkerOptions()
.position(new LatLng(Double.parseDouble(destLatitude), Double.parseDouble(destLongitude)))
.title(getLocationStringAddress(new LatLng(Double.parseDouble(destLatitude), Double.parseDouble(destLongitude))))
// .snippet(getLocationStringAddress(new LatLng(Double.parseDouble(destLatitude), Double.parseDouble(destLongitude))))
.icon(BitmapDescriptorFactory.fromResource(R.mipmap.map_set_marker)));
}
}