绘制目标android映射v2的路径

Question

我有一些代码显示目的地已初始化的两个方向（已知位置）。像这样的完整代码：

package com.my.app;

import java.io.IOException;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.URL;
import java.util.ArrayList;
import java.util.List;

import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.ParserConfigurationException;

import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;
import org.xml.sax.SAXException;

import android.app.Activity;
import android.app.AlertDialog;
import android.app.ProgressDialog;
import android.content.DialogInterface;
import android.graphics.Color;
import android.os.AsyncTask;
import android.os.Bundle;

import android.app.FragmentManager;
import android.util.Log;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.Toast;

import com.google.android.gms.common.ConnectionResult;
import com.google.android.gms.common.GooglePlayServicesUtil;
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.model.LatLng;
import com.google.android.gms.maps.model.MarkerOptions;
import com.google.android.gms.maps.model.PolylineOptions;
import android.support.v4.app.FragmentActivity;
import com.google.android.gms.maps.SupportMapFragment;
import android.location.Criteria;
import android.location.Location;
import android.location.LocationManager;
import android.app.AlertDialog;
import android.content.Context;
import android.content.DialogInterface;
import android.content.Intent;
import android.widget.RadioGroup;
import android.widget.RadioGroup.OnCheckedChangeListener;



public class CobaMap2 extends FragmentActivity {
final int RQS_GooglePlayServices = 1;
private GoogleMap myMap;
double src_lat = -7.81016;
double src_long = 110.46860;
double dest_lat = -7.778031;
double dest_long = 110.494180;
MarkerOptions markerOptions;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.map_layout2);

myMap = ((SupportMapFragment) getSupportFragmentManager().findFragmentById(R.id.map)).getMap();
myMap.setMyLocationEnabled(true);
// Set Current Location
moveToMyLocation();}
private void moveToMyLocation()
{
LocationManager locationManager = (LocationManager)
getSystemService(Context.LOCATION_SERVICE);
Criteria criteria = new Criteria();
Location location = locationManager.getLastKnownLocation(locationManager.getBestProvider(criteria, false));
if (location != null)
{
 myMap.animateCamera(CameraUpdateFactory.newLatLngZoom(
new LatLng(location.getLatitude(), 
location.getLongitude()), 13));
}



// choose map layout

RadioGroup rgViews = (RadioGroup) findViewById(R.id.rg_views);

rgViews.setOnCheckedChangeListener(new OnCheckedChangeListener() {

    @Override
    public void onCheckedChanged(RadioGroup group, int checkedId) {
        if(checkedId == R.id.rb_normal){
            myMap.setMapType(GoogleMap.MAP_TYPE_NORMAL);
        }else if(checkedId == R.id.rb_satellite){
            myMap.setMapType(GoogleMap.MAP_TYPE_HYBRID);
        }else if(checkedId == R.id.rb_terrain){
            myMap.setMapType(GoogleMap.MAP_TYPE_TERRAIN);
        }

    }
});




LatLng srcLatLng = new LatLng(src_lat, src_long);
LatLng destLatLng = new LatLng(dest_lat, dest_long);

myMap.addMarker(new MarkerOptions()
.position(srcLatLng).title("Source place"));

myMap.animateCamera(CameraUpdateFactory.newLatLng(srcLatLng));

myMap.addMarker(new MarkerOptions()
.position(destLatLng).title("Destination place"));

// Enabling MyLocation in Google Map
myMap.setMyLocationEnabled(true);
myMap.getUiSettings().setZoomControlsEnabled(true);
myMap.getUiSettings().setCompassEnabled(true);
myMap.getUiSettings().setMyLocationButtonEnabled(true);
myMap.getUiSettings().setAllGesturesEnabled(true);
myMap.setTrafficEnabled(true);
myMap.animateCamera(CameraUpdateFactory.newLatLngZoom(srcLatLng,12));
        markerOptions = new MarkerOptions();


// Polyline line = myMap.addPolyline(new PolylineOptions().add(srcLatLng, destLatLng).width(5).color(Color.RED));

connectAsyncTask _connectAsyncTask = new connectAsyncTask();
         _connectAsyncTask.execute();

}

@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.cobamap, menu);
return true;
}

@Override
public boolean onOptionsItemSelected(MenuItem item) {
switch (item.getItemId()) {
case R.id.menu_legalnotices:
String LicenseInfo = GooglePlayServicesUtil.getOpenSourceSoftwareLicenseInfo(
getApplicationContext());
AlertDialog.Builder LicenseDialog = new AlertDialog.Builder(CobaMap2.this);
LicenseDialog.setTitle("Legal Notices");
LicenseDialog.setMessage(LicenseInfo);
LicenseDialog.show();
return true;
}
return super.onOptionsItemSelected(item);
}

@Override
protected void onResume() {
// TODO Auto-generated method stub
super.onResume();

int resultCode = GooglePlayServicesUtil.isGooglePlayServicesAvailable(getApplicationContext());

if (resultCode == ConnectionResult.SUCCESS){
Toast.makeText(getApplicationContext(),
"isGooglePlayServicesAvailable SUCCESS",
Toast.LENGTH_LONG).show();
}else{
GooglePlayServicesUtil.getErrorDialog(resultCode, this, RQS_GooglePlayServices);
}

}

private class connectAsyncTask extends AsyncTask<Void, Void, Void>{
private ProgressDialog progressDialog;

@Override
protected void onPreExecute() {
// TODO Auto-generated method stub
super.onPreExecute();
progressDialog = new ProgressDialog(CobaMap2.this);
progressDialog.setMessage("Fetching route, Please wait...");
progressDialog.setIndeterminate(true);
progressDialog.show();
}
@Override
protected Void doInBackground(Void... params) {
// TODO Auto-generated method stub
fetchData();
return null;
}
@Override
protected void onPostExecute(Void result) {
// TODO Auto-generated method stub
super.onPostExecute(result);
if(doc!=null){
NodeList _nodelist = doc.getElementsByTagName("status");
Node node1 = _nodelist.item(0);
String _status1 = node1.getChildNodes().item(0).getNodeValue();
if(_status1.equalsIgnoreCase("OK")){
NodeList _nodelist_path = doc.getElementsByTagName("overview_polyline");
Node node_path = _nodelist_path.item(0);
Element _status_path = (Element)node_path;
NodeList _nodelist_destination_path = _status_path.getElementsByTagName("points");
Node _nodelist_dest = _nodelist_destination_path.item(0);
String _path = _nodelist_dest.getChildNodes().item(0).getNodeValue();
List<LatLng> directionPoint = decodePoly(_path);

PolylineOptions rectLine = new PolylineOptions().width(10).color(Color.BLUE);
for (int i = 0; i < directionPoint.size(); i++) {
rectLine.add(directionPoint.get(i));
}
// Adding route on the map
myMap.addPolyline(rectLine);
markerOptions.position(new LatLng(dest_lat, dest_long));
markerOptions.draggable(true);
myMap.addMarker(markerOptions);
}else{
showAlert("Unable to find the route");
}


}else{
showAlert("Unable to find the route");
}

progressDialog.dismiss();

}

}

Document doc = null;
private void fetchData()
{   
StringBuilder urlString = new StringBuilder();
urlString.append("http://maps.google.com/maps/api/directions/xml?origin=");
urlString.append(src_lat);
urlString.append(",");
urlString.append(src_long);
urlString.append("&destination=");//to
urlString.append(dest_lat);
urlString.append(",");
urlString.append(dest_long);
urlString.append("&sensor=true&mode=driving");
Log.d("url","::"+urlString.toString());
HttpURLConnection urlConnection= null;
URL url = null;
try
{
url = new URL(urlString.toString());
urlConnection=(HttpURLConnection)url.openConnection();
urlConnection.setRequestMethod("GET");
urlConnection.setDoOutput(true);
urlConnection.setDoInput(true);
urlConnection.connect();
DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
DocumentBuilder db = dbf.newDocumentBuilder();
doc = (Document) db.parse(urlConnection.getInputStream());//Util.XMLfromString(response);
}catch (MalformedURLException e){
e.printStackTrace();
}catch (IOException e){
e.printStackTrace();
}catch (ParserConfigurationException e){
e.printStackTrace();
}
catch (SAXException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}


private void showAlert(String message){
AlertDialog.Builder alert = new AlertDialog.Builder(CobaMap2.this);
alert.setTitle("Error");
alert.setCancelable(false);
alert.setMessage(message);
alert.setPositiveButton("Ok",new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int which) {
// TODO Auto-generated method stub

}
});
alert.show();
}

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;
}
}

代码工作正常，您可以看到两个位置（源和目标）之间的已知位置。然后我需要使用当前位置更改第一个位置（源位置），并使用此代码检测当前位置：

// Set Current Location
moveToMyLocation();}
private void moveToMyLocation()
{
LocationManager locationManager = (LocationManager)
getSystemService(Context.LOCATION_SERVICE);
Criteria criteria = new Criteria();
Location location = locationManager.getLastKnownLocation(locationManager.getBestProvider(criteria, false));
if (location != null)
{
 myMap.animateCamera(CameraUpdateFactory.newLatLngZoom(
new LatLng(location.getLatitude(), 
location.getLongitude()), 13));
}

初始化位置的代码是：

LatLng srcLatLng = new LatLng(src_lat, src_long);
    LatLng destLatLng = new LatLng(dest_lat, dest_long);

问题是，如何从当前位置传递数据以设置源位置的数据并显示位置之间的路径。 （来源：我目前的位置，目的地：已知位置）。我必须使用什么方法？我的意思是应用程序从我当前位置显示到目标位置并修改该代码？

Answer 1

检查此问题

How to draw interactive Polyline on route google maps v2 android

在此您将获得使用 polyLine 从一个地方到另一个地方绘制正确路线的代码，还包括当前和目的地位置！

修改：

使用

src_lat=location.getLatitude() 
src_long=location.getLongitude()

内

if (location != null)
{
src_lat=location.getLatitude() 
src_long=location.getLongitude()
 myMap.animateCamera(CameraUpdateFactory.newLatLngZoom(
new LatLng(location.getLatitude(), 
location.getLongitude()), 13));
}

修改  试试看 改变：

Location location = locationManager.getLastKnownLocation(locationManager.getBestProvider(criteria, false));

到

Location location = locationManager.getLastKnownLocation(locationManager.getBestProvider(criteria, true));