在2个位置之间未显示折线，但显示了时间和距离 [英] Polylines are not showing between 2 Locations but Time and Distance is showing

问题描述

注意:对不起，我的英语不好，因为英语不是我的母语，因此我使用Google翻译.

我正在使用一个Android地图应用程序，用户可以在其中找到朋友的当前位置.为了存储当前位置，我正在使用Firebase实时数据库.在Lalit Singh的先前帮助下，它现在正在显示时间和距离，但仍未更新2个不同位置之间的折线.我的更新代码如下.

I am working on an Android map app in which a user can find their friends' current location. For storing the current location I am using Firebase real time database. With previous help of Lalit Singh it is showing time and distance now but still not updating the Polylines between 2 different places. My updates code is below.

mapsActivity.java(从火场获取朋友位置，并调用更新的时间，距离和折线方法)

mapsActivity.java (where i am getting friend location from fire base and updated time, distance and polylines method called)

  public void proceed(final View view) {

    DatabaseReference ref = FirebaseDatabase.getInstance().getReference().child("Email");

    ref.addValueEventListener(new ValueEventListener() {
        @Override
        public void onDataChange(DataSnapshot dataSnapshot) {
            for (DataSnapshot dataSnapshot1 : dataSnapshot.getChildren()) {
                UserInformation details = dataSnapshot1.getValue(UserInformation.class);

                if (mMap != null) {
                    mMap.clear();
                }

                MarkerOptions markerOptions = new MarkerOptions();
                LatLng latLng1 = new LatLng(details.getLatitude(), details.getLongitude());
                markerOptions.position(latLng1);
                markerOptions.title(String.valueOf(latLng1));
                mMap.addMarker(markerOptions).setIcon(BitmapDescriptorFactory.defaultMarker(BitmapDescriptorFactory.HUE_GREEN));
                mMap.setMapType(GoogleMap.MAP_TYPE_HYBRID);
                mMap.moveCamera(CameraUpdateFactory.newLatLng(latLng1));
                mMap.animateCamera(CameraUpdateFactory.zoomTo(14));

                distance_task.getDirectionsUrl(latLng1, markerOptions.getPosition());
                distance_task.setLoadListener(new CalculateDistanceTime.taskCompleteListener() {
                    @Override
                    public void taskCompleted(String[] time_distance) {
                        text1.setText(time_distance[0]); //Distance
                        text2.setText(time_distance[1]); //Time
                    }
                });

                String url = getDirectionsUrl(latLng1, markerOptions.getPosition());
                DownloadTask downloadTask = new DownloadTask();
                downloadTask.execute(url);
            }
        }

        @Override
        public void onCancelled(DatabaseError databaseError) {

        }
    });
}

CalculateDistanceTime.java(添加了新类)

CalculateDistanceTime.java (added new Class)

class CalculateDistanceTime {     private taskCompleteListener
mTaskListener; private Context mContext;      
CalculateDistanceTime(Context context) {
mContext = context; }     void setLoadListener(taskCompleteListener taskListener) {
mTaskListener = taskListener; }        void 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;


DownloadTask downloadTask = new DownloadTask();

// Start downloading json data from Google Directions API

downloadTask.execute(url); }

private String downloadUrl(String strUrl) throws IOException {
String data = "";
HttpURLConnection urlConnection;
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
try (InputStream iStream = urlConnection.getInputStream()) {
    BufferedReader br = new BufferedReader(new InputStreamReader(iStream));

    StringBuilder sb = new StringBuilder();

    String line;
    while ((line = br.readLine()) != null) {
        sb.append(line);
    }

    data = sb.toString();

    br.close();

} catch (Exception e) {
    Log.d("Excp. while downloading", e.toString());
} finally {
    urlConnection.disconnect();
}
return data; }

interface taskCompleteListener {
void taskCompleted(String[] time_distance); }

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);

} }

private class ParserTask extends AsyncTask<String, Integer,
List<HashMap<String, String>>> {

// Parsing the data in non-ui thread
@Override
protected List<HashMap<String, String>> doInBackground(String... jsonData) {

    JSONObject jObject;
    List<HashMap<String, String>> routes = null;

    try {
        jObject = new JSONObject(jsonData[0]);
        DistanceTimeParser parser = new DistanceTimeParser();

        // 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<HashMap<String, String>> result) {

    String duration_distance = "";


    if (result.size() < 1) {
        Log.e("Error : ", "No Points found");
        return;
    }


    String[] date_dist = new String[2];

    // Traversing through all the routes
    for (int i = 0; i < result.size(); i++) {

        // Fetching i-th route
        HashMap<String, String> tmpData = result.get(i);
        Set<String> key = tmpData.keySet();
        Iterator it = key.iterator();
        while (it.hasNext()) {
            String hmKey = (String) it.next();
            duration_distance = tmpData.get(hmKey);

            System.out.println("Key: " + hmKey + " & Data: " + duration_distance);

            it.remove(); // avoids a ConcurrentModificationException
        }

        date_dist[i] = duration_distance;
    }

    mTaskListener.taskCompleted(date_dist);
}   } }

DistanceTimeParser.java(添加了新类)

DistanceTimeParser.java (added new class)

public class DistanceTimeParser {
public List<HashMap<String, String>> parse(JSONObject jObject) {


    List<HashMap<String, String>> routes = new ArrayList<HashMap<String, String>>();
    JSONArray jRoutes = null;
    JSONArray jLegs = null;

    JSONObject jDistance = null;
    JSONObject jDuration = null;

    try {

        jRoutes = jObject.getJSONArray("routes");

        jLegs = ((JSONObject) jRoutes.get(0)).getJSONArray("legs");

        List<HashMap<String, String>> path = new ArrayList<HashMap<String, String>>();


        /** Getting distance from the json data */
        jDistance = ((JSONObject) jLegs.get(0)).getJSONObject("distance");
        HashMap<String, String> hmDistance = new HashMap<String, String>();
        hmDistance.put("distance", jDistance.getString("text"));

        /** Getting duration from the json data */
        jDuration = ((JSONObject) jLegs.get(0)).getJSONObject("duration");
        HashMap<String, String> hmDuration = new HashMap<String, String>();
        hmDuration.put("duration", jDuration.getString("text"));

        routes.add(hmDistance);

        routes.add(hmDuration);

    } catch (JSONException e) {
        e.printStackTrace();
    } catch (Exception e) {
    }

    return routes;
} }

DirectionsJSONParser.java(添加了新类)

DirectionsJSONParser.java (added new class)

public class DirectionsJSONParser {

List<List<HashMap<String,String>>> parse(JSONObject jObject){

    List<List<HashMap<String, String>>> routes = new ArrayList<>() ;
    JSONArray jRoutes ;
    JSONArray jLegs ;
    JSONArray jSteps ;

    try {

        jRoutes = jObject.getJSONArray("routes");


        for(int i=0;i<jRoutes.length();i++){
            jLegs = ( (JSONObject)jRoutes.get(i)).getJSONArray("legs");
            List path = new ArrayList<>();

            for(int j=0;j<jLegs.length();j++){
                jSteps = ( (JSONObject)jLegs.get(j)).getJSONArray("steps");


                for(int k=0;k<jSteps.length();k++){
                    String polyline;
                    polyline = (String)((JSONObject)((JSONObject)jSteps.get(k)).get("polyline")).get("points");
                    List<LatLng> list = decodePoly(polyline);


                    for(int l=0;l<list.size();l++){
                        HashMap<String, String> hm = new HashMap<>();
                        hm.put("lat", Double.toString((list.get(l)).latitude) );
                        hm.put("lng", Double.toString((list.get(l)).longitude) );
                        path.add(hm);
                    }
                }
                routes.add(path);
            }
        }

    } catch (JSONException e) {
        e.printStackTrace();
    }catch (Exception ignored){
    }

    return routes;
}

private List<LatLng> decodePoly(String encoded) {

    List<LatLng> poly = new ArrayList<>();
    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;
} }

在mapsActivity.java中添加了这4种方法

These 4 methods added in mapsActivity.java

  private String getDirectionsUrl(LatLng origin, LatLng dest) {

    String str_origin = "origin=" + origin.latitude + "," + origin.longitude;

    String str_dest = "destination=" + dest.latitude + "," + dest.longitude;

    String sensor = "sensor=false";

    String parameters = str_origin + "&" + str_dest + "&" + sensor;

    String output = "json";

    return "https://maps.googleapis.com/maps/api/directions/" + output + "?" + parameters;
}

  @SuppressLint("NewApi")
  public static String downloadUrl(String strUrl) throws IOException {
    String data = "";
    HttpURLConnection urlConnection;
    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
    try (InputStream iStream = urlConnection.getInputStream()) {
        BufferedReader br = new BufferedReader(new InputStreamReader(iStream));

        StringBuilder sb = new StringBuilder();

        String line;
        while ((line = br.readLine()) != null) {
            sb.append(line);
        }

        data = sb.toString();

        br.close();

    } catch (Exception e) {
        Log.d("Exception while down", e.toString());
    } finally {
        urlConnection.disconnect();
    }
    return data;
}

  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);
    }
}

private class ParserTask extends AsyncTask<String, Integer, List<List<HashMap<String, String>>>> {

    @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;
    }

    @Override
    protected void onPostExecute(List<List<HashMap<String, String>>> result) {
        ArrayList<LatLng> points = new ArrayList<>();
        PolylineOptions lineOptions = new PolylineOptions();
        for (int i = 0; i < result.size(); i++) {
            List<HashMap<String, String>> path = result.get(i);
            for (int j = 0; j < path.size(); j++) {
                HashMap<String, String> point = path.get(j);
                double lat = Double.parseDouble(point.get("lat"));
                double lng = Double.parseDouble(point.get("lng"));
                LatLng position = new LatLng(lat, lng);
                points.add(position);
            }
            lineOptions.addAll(points);
            lineOptions.width(10);
            lineOptions.color(Color.WHITE);
            mMap.addPolyline(lineOptions);
        }
    }
}

mapsActivity.java(我在地图上的当前位置)

mapsActivity.java (my current location in map)

@Override
public void onLocationChanged(Location location) {
    Log.d("onLocationChanged", "entered");

    mLastLocation = location;

    DateFormat dateFormat = new SimpleDateFormat("yyyy/MM/dd HH:mm:ss");
    dateFormat.setTimeZone(TimeZone.getTimeZone("UTC"));
    Date date = new Date();
    mLastUpdateTime = ((dateFormat.format(date).toString()));

    saveToFirebase();

    if (mCurrLocationMarker != null) {
        mCurrLocationMarker.remove();
    }

    latitude = location.getLatitude();
    longitude = location.getLongitude();

    LatLng latLng = new LatLng(location.getLatitude(), location.getLongitude());
    MarkerOptions markerOptions = new MarkerOptions();
    markerOptions.position(latLng);
    markerOptions.draggable(false);
    markerOptions.title("Current Position");
    markerOptions.icon(BitmapDescriptorFactory.defaultMarker(BitmapDescriptorFactory.HUE_MAGENTA));
    mCurrLocationMarker = mMap.addMarker(markerOptions);

    //move map camera
    mMap.moveCamera(CameraUpdateFactory.newLatLng(latLng));
    mMap.animateCamera(CameraUpdateFactory.zoomTo(11));

    Toast.makeText(MapsActivity.this, "Your Current Location", Toast.LENGTH_LONG).show();

    //stop location updates
    if (mGoogleApiClient != null) {
     LocationServices.FusedLocationApi.removeLocationUpdates(mGoogleApiClient,
   this);
        Log.d("onLocationChanged", "Removing Location Updates");
    }
}

以Fire Base方法保存的数据

Data Saved in Fire Base Method

public void saveToFirebase() {

    DatabaseReference ref = FirebaseDatabase.getInstance().getReference().child("Email").push();
    String email = FirebaseAuth.getInstance().getCurrentUser().getEmail();
    UserInformation userInformation = new UserInformation(email, mLastLocation.getLatitude(), mLastLocation.getLongitude());
    ref.setValue(userInformation);
}

推荐答案

我假设您需要路线，距离和时间. 首先创建这3个类.

I'm assuming that you need Route, Distance and Time. First Create these 3 classes.

1. CalculateDistanceTime.java

1. CalculateDistanceTime.java

import android.content.Context;
import android.os.AsyncTask;
import android.util.Log;    
import com.google.android.gms.maps.model.LatLng;    
import org.json.JSONObject;    
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.net.HttpURLConnection;
import java.net.URL;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Set;    
class CalculateDistanceTime {    
private taskCompleteListener mTaskListener;
private Context mContext;      
CalculateDistanceTime(Context context) {
    mContext = context;
}    
void setLoadListener(taskCompleteListener taskListener) {
    mTaskListener = taskListener;
}       
void 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;


    DownloadTask downloadTask = new DownloadTask();

    // Start downloading json data from Google Directions API

    downloadTask.execute(url);
}

private String downloadUrl(String strUrl) throws IOException {
    String data = "";
    HttpURLConnection urlConnection;
    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
    try (InputStream iStream = urlConnection.getInputStream()) {
        BufferedReader br = new BufferedReader(new InputStreamReader(iStream));

        StringBuilder sb = new StringBuilder();

        String line;
        while ((line = br.readLine()) != null) {
            sb.append(line);
        }

        data = sb.toString();

        br.close();

    } catch (Exception e) {
        Log.d("Excp. while downloading", e.toString());
    } finally {
        urlConnection.disconnect();
    }
    return data;
}


interface taskCompleteListener {
    void taskCompleted(String[] time_distance);
}

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);

    }
}

private class ParserTask extends AsyncTask<String, Integer, List<HashMap<String, String>>> {

    // Parsing the data in non-ui thread
    @Override
    protected List<HashMap<String, String>> doInBackground(String... jsonData) {

        JSONObject jObject;
        List<HashMap<String, String>> routes = null;

        try {
            jObject = new JSONObject(jsonData[0]);
            DistanceTimeParser parser = new DistanceTimeParser();

            // 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<HashMap<String, String>> result) {

        String duration_distance = "";


        if (result.size() < 1) {
            Log.e("Error : ", "No Points found");
            return;
        }


        String[] date_dist = new String[2];

        // Traversing through all the routes
        for (int i = 0; i < result.size(); i++) {

            // Fetching i-th route
            HashMap<String, String> tmpData = result.get(i);
            Set<String> key = tmpData.keySet();
            Iterator it = key.iterator();
            while (it.hasNext()) {
                String hmKey = (String) it.next();
                duration_distance = tmpData.get(hmKey);

                System.out.println("Key: " + hmKey + " & Data: " + duration_distance);

                it.remove(); // avoids a ConcurrentModificationException
            }

            date_dist[i] = duration_distance;
        }

        mTaskListener.taskCompleted(date_dist);
    }
  }
}

DistanceTimeParser.java

DistanceTimeParser.java

import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;

public class DistanceTimeParser {
    public List<HashMap<String, String>> parse(JSONObject jObject) {


    List<HashMap<String, String>> routes = new ArrayList<HashMap<String, String>>();
    JSONArray jRoutes = null;
    JSONArray jLegs = null;

    JSONObject jDistance = null;
    JSONObject jDuration = null;

    try {

        jRoutes = jObject.getJSONArray("routes");

        jLegs = ((JSONObject) jRoutes.get(0)).getJSONArray("legs");

        List<HashMap<String, String>> path = new ArrayList<HashMap<String, String>>();


        /** Getting distance from the json data */
        jDistance = ((JSONObject) jLegs.get(0)).getJSONObject("distance");
        HashMap<String, String> hmDistance = new HashMap<String, String>();
        hmDistance.put("distance", jDistance.getString("text"));

        /** Getting duration from the json data */
        jDuration = ((JSONObject) jLegs.get(0)).getJSONObject("duration");
        HashMap<String, String> hmDuration = new HashMap<String, String>();
        hmDuration.put("duration", jDuration.getString("text"));

        routes.add(hmDistance);

        routes.add(hmDuration);

    } catch (JSONException e) {
        e.printStackTrace();
    } catch (Exception e) {
    }

    return routes;
}
}

DirectionsJSONParser.java

DirectionsJSONParser.java

import com.google.android.gms.maps.model.LatLng;    
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;    
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
class DirectionsJSONParser {


List<List<HashMap<String,String>>> parse(JSONObject jObject){

    List<List<HashMap<String, String>>> routes = new ArrayList<>() ;
    JSONArray jRoutes ;
    JSONArray jLegs ;
    JSONArray jSteps ;

    try {

        jRoutes = jObject.getJSONArray("routes");


        for(int i=0;i<jRoutes.length();i++){
            jLegs = ( (JSONObject)jRoutes.get(i)).getJSONArray("legs");
            List path = new ArrayList<>();

            for(int j=0;j<jLegs.length();j++){
                jSteps = ( (JSONObject)jLegs.get(j)).getJSONArray("steps");


                for(int k=0;k<jSteps.length();k++){
                    String polyline;
                    polyline = (String)((JSONObject)((JSONObject)jSteps.get(k)).get("polyline")).get("points");
                    List<LatLng> list = decodePoly(polyline);


                    for(int l=0;l<list.size();l++){
                        HashMap<String, String> hm = new HashMap<>();
                        hm.put("lat", Double.toString((list.get(l)).latitude) );
                        hm.put("lng", Double.toString((list.get(l)).longitude) );
                        path.add(hm);
                    }
                }
                routes.add(path);
            }
        }

    } catch (JSONException e) {
        e.printStackTrace();
    }catch (Exception ignored){
    }

    return routes;
}

private List<LatLng> decodePoly(String encoded) {

    List<LatLng> poly = new ArrayList<>();
    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;
}
}

简单地复制了这三个文件. 您可以对任何MapsActivity执行以下操作.
这是您可以在任何活动中使用以下代码的地方，并且以上代码对于每种活动都将保持不变(方向图).

创建一个全局变量CalculateDistanceTime distance_task;.
在onCreate中将其初始化为distance_task = new CalculateDistanceTime(this);

After simply copying these three files. What you can do is the following for any MapsActivity.
This is the point where you can use below code in any activity and above code will remain same for every acitivity(Maps for Directions).

Create a global variable CalculateDistanceTime distance_task;.
Initialize it in the onCreate as distance_task = new CalculateDistanceTime(this);

将这4种方法发布到您的MapsActivity.java中.

Post this 4 methods in your MapsActivity.java.

private String getDirectionsUrl(LatLng origin, LatLng dest) {

        String str_origin = "origin=" + origin.latitude + "," + origin.longitude;


        String str_dest = "destination=" + dest.latitude + "," + dest.longitude;


        String sensor = "sensor=false";


        String parameters = str_origin + "&" + str_dest + "&" + sensor;

        String output = "json";


        return "https://maps.googleapis.com/maps/api/directions/" + output + "?" + parameters;
    }

    public static String downloadUrl(String strUrl) throws IOException {
        String data = "";
        HttpURLConnection urlConnection;
        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
        try (InputStream iStream = urlConnection.getInputStream()) {
            BufferedReader br = new BufferedReader(new InputStreamReader(iStream));

            StringBuilder sb = new StringBuilder();

            String line;
            while ((line = br.readLine()) != null) {
                sb.append(line);
            }

            data = sb.toString();

            br.close();

        } catch (Exception e) {
            Log.d("Exception while down", e.toString());
        } finally {
            urlConnection.disconnect();
        }
        return data;
    }

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);
        }
    }

private class ParserTask extends AsyncTask<String, Integer, List<List<HashMap<String, String>>>> {

        @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;
        }

        @Override
        protected void onPostExecute(List<List<HashMap<String, String>>> result) {
            ArrayList<LatLng> points = new ArrayList<>();
            lineOptions = new PolylineOptions();
            for (int i = 0; i < result.size(); i++) {
                List<HashMap<String, String>> path = result.get(i);
                for (int j = 0; j < path.size(); j++) {
                    HashMap<String, String> point = path.get(j);
                    double lat = Double.parseDouble(point.get("lat"));
                    double lng = Double.parseDouble(point.get("lng"));
                    LatLng position = new LatLng(lat, lng);
                    points.add(position);
                }
                lineOptions.addAll(points);
                lineOptions.width(10);                   
                lineOptions.color(Color.WHITE);
                googleMap.addPolyline(lineOptions);                
        }
    }

这时，您已经拥有了所有需要的代码.
现在，使用以下代码传递您所在位置和朋友所在位置的名称，您将获得时间距离和路线.

At this point you have all the needed code.
Now use the following code passing the latlngs of your location and friend's location and you'll have Time Distance and Route.:

               distance_task.getDirectionsUrl(latLng1, latLng2);
               distance_task.setLoadListener(new CalculateDistanceTime.taskCompleteListener() {
                        @Override
                        public void taskCompleted(String[] time_distance) {
                            text1.setText(time_distance[0]); //Distance
                            text2.setText(time_distance[1]); //Time
                        }
                    });
               String url = getDirectionsUrl(latLng1, latLng2);
               DownloadTask downloadTask = new DownloadTask();
               downloadTask.execute(url);

要显示距离和时间，您必须创建两个TextView(请参见上面的text1和Text2).

For displaying Distance and Time, You have to create two TextView (see text1 and Text2 above).

这篇关于在2个位置之间未显示折线，但显示了时间和距离的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！