我想在我的城市制作关于公共交通导航仪的应用程序，但我不知道应该用什么来绘制谷歌地图中的路线，有人可以提供解决方案吗？
是A到B而B到A只是使用一条路线还是两条路线？以及如何将其导入谷歌地图？我也使用android studio。
答案 0 :(得分：0)
package com.ibl.googlemap;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;
import com.google.android.gms.maps.model.LatLng;
public class DirectionsJSONParser {
/**
* Receives a JSONObject and returns a list of lists containing latitude and
* longitude
*/
public List<List<HashMap<String, String>>> parse(JSONObject jObject) {
List<List<HashMap<String, String>>> routes = new ArrayList<List<HashMap<String, String>>>();
JSONArray jRoutes = null;
JSONArray jLegs = null;
JSONArray jSteps = null;
try {
jRoutes = jObject.getJSONArray("routes");
/** Traversing all routes */
for (int i = 0; i < jRoutes.length(); i++) {
jLegs = ((JSONObject) jRoutes.get(i)).getJSONArray("legs");
List path = new ArrayList<HashMap<String, String>>();
/** Traversing all legs */
for (int j = 0; j < jLegs.length(); j++) {
jSteps = ((JSONObject) jLegs.get(j)).getJSONArray("steps");
/** Traversing all 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);
/** Traversing all points */
for (int l = 0; l < list.size(); l++) {
HashMap<String, String> hm = new HashMap<String, String>();
hm.put("lat",
Double.toString(((LatLng) list.get(l)).latitude));
hm.put("lng",
Double.toString(((LatLng) list.get(l)).longitude));
path.add(hm);
}
}
routes.add(path);
}
}
} catch (JSONException e) {
e.printStackTrace();
} catch (Exception e) {
}
return routes;
}
/**
* Method to decode polyline points Courtesy :
* http://jeffreysambells.com/2010
* /05/27/decoding-polylines-from-google-maps-direction-api-with-java
* */
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;
}
}
package com.ibl.googlemap;
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.text.DecimalFormat;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import org.json.JSONException;
import org.json.JSONObject;
import android.app.ProgressDialog;
import android.content.Intent;
import android.graphics.Color;
import android.os.AsyncTask;
import android.os.Bundle;
import android.support.v4.app.FragmentActivity;
import android.util.Log;
import android.view.KeyEvent;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.RelativeLayout;
import android.widget.Toast;
import com.google.android.gms.maps.CameraUpdateFactory;
import com.google.android.gms.maps.GoogleMap;
import com.google.android.gms.maps.GoogleMap.OnMapClickListener;
import com.google.android.gms.maps.SupportMapFragment;
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.ibl.comman.GPSTracker;
import com.ibl.foodpulse.CreateShareDeal;
import com.ibl.foodpulse.R;
public class ViewMapDirection extends FragmentActivity implements OnClickListener {
private GoogleMap map;
private ArrayList<LatLng> markerPoints;
private Button btnShow;
private double ans;
private GPSTracker gps; // this is current location
private double latitude, longitude;
// this is user current location lat lng
private double longitude2, latitude2;
private int bcid;
private int vuid;
String res = "";
String url2;
Boolean checknet = true;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.googlemap_only_activity);
gps = new GPSTracker(ViewMapDirection.this);
Bundle b = getIntent().getExtras();
latitude = b.getFloat("lat"); // hear i got lat lng from last activity.
longitude = b.getFloat("longy");
Log.e("View Map Direction", "get the Lat and Lng :" + latitude + " :: " + longitude);
if (gps.canGetLocation()) {
// please set here your current location and hide this method
latitude2 = gps.getLatitude();
longitude2 = gps.getLongitude();
// hear i will got current location from GPS Tracker
Log.e("View Map Direction ", " get Current Lat lng " + latitude2 + " lng " + longitude2);
} else {
gps.showSettingsAlert(ViewMapDirection.this, ViewMapDirection.this);
}
Intent j = getIntent();
bcid = j.getIntExtra("BCARD_ID", 0);
vuid = j.getIntExtra("VUID1", 0);
btnShow = (Button) findViewById(R.id.btn_onlywebview_close);
SupportMapFragment fm = (SupportMapFragment) getSupportFragmentManager()
.findFragmentById(R.id.map_googlemapAct);
// Getting Map for the SupportMapFragment
map = fm.getMap();
/*
* db=new MyDBHandler(this); gp=db.getGPSdata(bcid);
*/
btnShow.setOnClickListener(this);
}
// Initializing
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";
// Start
int Radius = 6371;// radius of earth in Km
double lat1 = origin.latitude;
double lat2 = dest.latitude;
double lon1 = origin.longitude;
double lon2 = dest.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);
ans = Radius * c;
// Toast.makeText(getApplicationContext(), "Result" + ans,
// Toast.LENGTH_SHORT).show();
// End
// 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 while downloading url", e.toString());
} finally {
iStream.close();
urlConnection.disconnect();
}
return data;
}
@Override
protected void onResume() {
// TODO Auto-generated method stub
super.onResume();
markerPoints = new ArrayList<LatLng>();
// Getting reference to SupportMapFragment of the
// activity_main
if (map != null) {
Log.e(" in View Map ", " in On Resume Method calling .........");
// if (gps.canGetLocation()) {
// latitude2 = gps.getLatitude();
// longitude2 = gps.getLongitude();
// Enable MyLocation Button in the Map
map.setMyLocationEnabled(true);
// Toast.makeText(getApplicationContext(),"Card Lattitude is
// "+gp.getGps_lattitude()+" LOngitude is
// "+gp.getGps_longitude(),Toast.LENGTH_LONG).show();
LatLng CardPoint = new LatLng(latitude, longitude);
// LatLng CardPoint=new
// LatLng(21.237425849325856,72.8330023214221);
Log.e(" in View Map ", " in On Card Point........." + CardPoint.latitude);
MarkerOptions Destpoint = new MarkerOptions();
Destpoint.position(CardPoint);
map.addMarker(Destpoint);
map.animateCamera(CameraUpdateFactory.newLatLngZoom(CardPoint, 10));
// Toast.makeText(getApplicationContext(),"Visitor Lattitude is
// "+latitude2+" LOngitude is
// "+longitude2,Toast.LENGTH_LONG).show();
LatLng UserPoint = new LatLng(latitude2, longitude2);
MarkerOptions Sourcepoint = new MarkerOptions();
Sourcepoint.position(UserPoint);
map.addMarker(Sourcepoint);
String url = getDirectionsUrl(UserPoint, CardPoint);
DownloadTask downloadTask = new DownloadTask();
downloadTask.execute(url);
// } else {
// gps.showSettingsAlert(ViewMapDirection.this);
// }
}
}
// 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 = "";
Log.e(" in View Map ", " in Download Task ........." + url.toString());
try {
// Fetching the data from web service
data = downloadUrl(url[0]);
} catch (Exception e) {
Log.e("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();
Log.e(" in View Map ", " in on Post .........");
// 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;
Log.e(" in View Map ", " in parser Task Calling .........");
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();
Log.e(" in View Map ", " in parser post ........." + result.size());
// Traversing through all the routes
for (int i = 0; i < result.size(); i++) {
Log.e(" in View Map ", " in Result For .........");
points = new ArrayList<LatLng>();
lineOptions = new PolylineOptions();
// Fetching i-th route
List<HashMap<String, String>> path = result.get(i);
Log.e(" in View Map ", " in path ........." + path.size());
// Fetching all the points in i-th route
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);
Log.e("in View Direction ", " lag ,,,,, " + lat + " lng ... " + lng);
points.add(position);
}
// Adding all the points in the route to LineOptions
lineOptions.addAll(points);
lineOptions.width(4);
lineOptions.color(Color.BLUE);
}
// Drawing polyline in the Google Map for the i-th route
// if (gps.canGetLocation()) {
// latitude2 = gps.getLatitude();
// longitude2 = gps.getLongitude();
if (map != null) {
if (gps.canGetLocation()) {
latitude2 = gps.getLatitude();
longitude2 = gps.getLongitude();
Log.e("View Map Direction ", " get Current Lat lng " + latitude2 + " lng " + longitude2);
if ((latitude != 0) && (longitude != 0)) {
map.addPolyline(lineOptions);
}
} else {
gps.showSettingsAlert(ViewMapDirection.this, ViewMapDirection.this);
}
}
// } else {
// gps.showSettingsAlert(ViewMapDirection.this);
// }
// onResume();
}
}
@Override
public void onClick(View v) {
// TODO Auto-generated method stub
switch (v.getId()) {
case R.id.btn_onlywebview_close:
finish();
break;
default:
break;
}
}
}
在上面的类中正确阅读并遵循它，因为这个类在我当前的项目中运行。 这在您的清单文件中设置
<provider
android:name="com.facebook.NativeAppCallContentProvider"
android:authorities="com.facebook.app.NativeAppCallContentProvider1621374528084848"
android:exported="true" />
<meta-data
android:name="com.google.android.maps.v2.API_KEY"
android:value="your key" />
<meta-data
android:name="com.google.android.gms.version"
android:value="@integer/google_play_services_version" />
你知道添加还需要谷歌播放服务lib。