Question

我想在两个lat lng点之间显示导航路线。起始位置可能与当前位置不同。我用Intent做这个任务，但我想没有意图。导航展示像优步出租车。我是android的新手。请帮帮我。提前谢谢。

Answer 1

你可以在getDirectionsUrl（LatLng origin，LatLng dest）函数中提供LatLan，你可以显示origin和dest之间的路径。

XML代码：

<RelativeLayout 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" >
    <RelativeLayout
        android:id="@+id/header"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:orientation="horizontal"
        android:background="@mipmap/gradiant"
        android:layout_alignParentTop="true"
        android:padding="6dp">

        <TextView
            android:id="@+id/activity_registration_txtTitle"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_centerInParent="true"
            android:textSize="16sp"
            android:textStyle="bold"
            android:text="Event Destination"/>
    </RelativeLayout>
   <fragment
    android:id="@+id/map"
    android:layout_below="@+id/header"
    android:name="com.google.android.gms.maps.MapFragment"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    />
    <TextView
        android:id="@+id/tv_distance_time"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_below="@+id/header"
        android:layout_alignParentLeft="true"
        android:layout_alignParentStart="true" />


</RelativeLayout>

Java代码：

import android.app.Activity;
import android.app.ProgressDialog;
import android.content.Intent;
import android.content.pm.PackageManager;
import android.graphics.Color;
import android.location.Address;
import android.location.Geocoder;
import android.location.Location;
import android.os.AsyncTask;
import android.os.Bundle;
import android.support.v4.app.ActivityCompat;
import android.util.Log;
import android.view.View;
import android.widget.TextView;
import android.widget.Toast;

import com.android.volley.DefaultRetryPolicy;
import com.android.volley.Request;
import com.android.volley.RequestQueue;
import com.android.volley.Response;
import com.android.volley.VolleyError;
import com.android.volley.toolbox.StringRequest;
import com.android.volley.toolbox.Volley;
import com.google.android.gms.common.ConnectionResult;
import com.google.android.gms.common.api.GoogleApiClient;
import com.google.android.gms.location.LocationServices;
import com.google.android.gms.maps.CameraUpdate;
import com.google.android.gms.maps.CameraUpdateFactory;
import com.google.android.gms.maps.GoogleMap;
import com.google.android.gms.maps.MapFragment;
import com.google.android.gms.maps.OnMapReadyCallback;
import com.google.android.gms.maps.model.BitmapDescriptorFactory;
import com.google.android.gms.maps.model.LatLng;
import com.google.android.gms.maps.model.Marker;
import com.google.android.gms.maps.model.MarkerOptions;
import com.google.android.gms.maps.model.PolylineOptions;
import com.mayur.aroundus.EventClass.Event;
import com.mayur.aroundus.Utility.CommonUtility;
import com.mayur.aroundus.Utility.DirectionsJSONParser;
import com.mayur.aroundus.Utility.GPSTracker;

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

public class MapsActivity extends Activity implements OnMapReadyCallback, com.google.android.gms.common.api.GoogleApiClient.ConnectionCallbacks, com.google.android.gms.common.api.GoogleApiClient.OnConnectionFailedListener {

    private static final String TAG ="AroundUs" ;
    private GoogleMap mMap;
    GPSTracker gps;
    protected GoogleApiClient mGoogleApiClient;
    protected Location mLastLocation;
    private double latitude = 0;
    private double longitude = 0;
    List<Event> lsEvent=new ArrayList<Event>();
    String destLatitude,destLongitude;
    TextView tvDistanceDuration;
    ArrayList<LatLng> markerPoints;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_maps);
        GPSTracker gps = new GPSTracker(MapsActivity.this);
        if(gps.canGetLocation()) {
            System.out.println("Latitude = "+gps.getLatitude()+" Longitude = "+
            gps.getLongitude());
        }
        markerPoints = new ArrayList<LatLng>();
        Intent intent = getIntent();
        destLatitude = intent.getStringExtra("Latitude");
        destLongitude = intent.getStringExtra("Longitude");
        buildGoogleApiClient();
    }


    protected synchronized void buildGoogleApiClient() {
        mGoogleApiClient = new GoogleApiClient.Builder(this)
                .addConnectionCallbacks(this)
                .addOnConnectionFailedListener(this)
                .addApi(LocationServices.API)
                .build();
    }

    @Override
    protected void onStart() {
        super.onStart();
        mGoogleApiClient.connect();
    }

    @Override
    protected void onStop() {
        super.onStop();
        if (mGoogleApiClient.isConnected()) {
            mGoogleApiClient.disconnect();
        }
    }

        //Runs when a GoogleApiClient object successfully connects.



    @Override
    public void onConnected(Bundle connectionHint) {

            mLastLocation = LocationServices.FusedLocationApi.getLastLocation(mGoogleApiClient);
        if (mLastLocation != null) {
            latitude=mLastLocation.getLatitude();
            longitude=mLastLocation.getLongitude();
            MapFragment mapFragment = (MapFragment) getFragmentManager().findFragmentById(R.id.map);
            mapFragment.getMapAsync(MapsActivity.this);
            tvDistanceDuration = (TextView) findViewById(R.id.tv_distance_time);


        } else {
            Toast.makeText(this, "no_location_detected", Toast.LENGTH_LONG).show();
        }
    }

    @Override
    public void onConnectionFailed(ConnectionResult result) {
        // Refer to the javadoc for ConnectionResult to see what error codes might be returned in
        // onConnectionFailed.
        Log.i(TAG, "Connection failed: ConnectionResult.getErrorCode() = " + result.getErrorCode());
    }


    @Override
    public void onConnectionSuspended(int cause) {
        // The connection to Google Play services was lost for some reason. We call connect() to
        // attempt to re-establish the connection.
        Log.i(TAG, "Connection suspended");
        mGoogleApiClient.connect();
    }



    @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 void call() {
        mMap.setOnMapClickListener(new GoogleMap.OnMapClickListener() {
            @Override
            public void onMapClick(LatLng latLng) {
                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);

            }
        });
    }

    public  String getLocationStringAddress(LatLng latLng){
        Geocoder geocoder = new Geocoder(MapsActivity.this, Locale.getDefault());
        String result = null;
        try {
//                    latitude=23.0590869;
//                    longitude=72.5557736;
                    latitude=latLng.latitude;
                    longitude=latLng.longitude;
                    List<Address> addressList = geocoder.getFromLocation(latitude, longitude, 1);
                    if (addressList != null && addressList.size() > 0) {
                        android.location.Address address = addressList.get(0);
                        StringBuilder sb = new StringBuilder();
//                        for (int i = 0; i < address.getMaxAddressLineIndex(); i++) {
//                            sb.append(address.getAddressLine(i)).append("\n");
//                        }
                        sb.append(address.getLocality()).append(", ");
//                        sb.append(address.getPostalCode()).append("\n");
                        sb.append(address.getCountryName());
                        result = sb.toString();
                    }
                } catch (IOException e) {
                    Log.e(TAG, "Unable connect to Geocoder", e);
                }
        return  result;
    }




    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)));
        }
    }

}

Answer 2

我制作了一条功能，可以在从原点到目的地的路线上绘制折线

public void markRoute(LatLng... value){
    LatLng startPoint = value[0];
    LatLng endPoint = value[1];
    LatLng midPoint = value[2];
    String url = "";
    if(midPoint != null)
        url = "https://maps.googleapis.com/maps/api/directions/" +
                "json?origin="+startPoint.latitude+","+startPoint.longitude+"&destination="+endPoint.latitude+","+endPoint.longitude+"&" +
                "waypoints="+midPoint.latitude+","+midPoint.longitude;
    else
        url = "https://maps.googleapis.com/maps/api/directions/" +
                "json?origin="+startPoint.latitude+","+startPoint.longitude+"&destination="+endPoint.latitude+","+endPoint.longitude;

        StringRequest stringRequest = new StringRequest(Request.Method.POST,url ,
                new Response.Listener<String>() {
                    @Override
                    public void onResponse(String result) {
                        JSONObject jsonResponse;
                        try {
                            jsonResponse = new JSONObject(result);
                            JSONArray routes = jsonResponse.getJSONArray("routes");
                            for (int i=0; i<routes.length(); i++) {
                                PolylineOptions options = new PolylineOptions().width(5).color(Color.BLUE).geodesic(true);
                                JSONArray legs = routes.getJSONObject(i).getJSONArray("legs");
                                for (int j=0; j<legs.length(); j++) {
                                    JSONArray steps = legs.getJSONObject(j).getJSONArray("steps");
                                    int lastItem = 0;
                                    for (int k=0; k<steps.length(); k++) {

                                        options.add(new LatLng(steps.getJSONObject(k).getJSONObject("start_location").getDouble("lat"),
                                                steps.getJSONObject(k).getJSONObject("start_location").getDouble("lng")));
                                        lastItem = k;

                                    }
                                    options.add(new LatLng(steps.getJSONObject(lastItem).getJSONObject("end_location").getDouble("lat"),
                                            steps.getJSONObject(lastItem).getJSONObject("end_location").getDouble("lng")));
                                }
                                mMap.addPolyline(options);
                            }
                        }
                        catch (JSONException e) {
                            e.printStackTrace();
                        }
                    }
                },
                new Response.ErrorListener() {
                    @Override
                    public void onErrorResponse(VolleyError error) {

                    }
                }){
            @Override
            protected Map<String,String> getParams(){
                Map<String,String> params = new HashMap<String, String>();
                return params;
            }
        };
        RequestQueue requestQueue = Volley.newRequestQueue(getApplicationContext());
        requestQueue.add(stringRequest);
}

此处mMap为GoogleMap，您获得onMapReady()

如果提供单点航点或中点，您可以将此功能称为。

markRoute(LatLng startPoint, LatLng endPoint, LatLng midPoint)

或者它也可以是，如果只提供源和目的地

markRoute(LatLng startPoint, LatLng endPoint)

来自您计划的任何地方。

如何在没有意图Android的Google Map中显示两个Lat Lng之间的导航

2 个答案: