目前在Google Map App中工作。我想在Android应用程序中使用Google transit API来绘制线Transit。但是代码只是为了划线驾驶。你能让我修改代码来画线Transit！
这是我的代码：
public class Main2Activity extends Activity {
final int RQS_GooglePlayServices = 1;
private GoogleMap myMap;
private double src_lat ;
private double src_long ;
private double dest_lat ;
private double dest_long ;
MarkerOptions markerOptions;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main2);
String gps1,gps2;
Intent intent = getIntent();
Bundle bundle = intent.getExtras();
gps1 = bundle.getString("origin");
gps2 = bundle.getString("destination");
String[] myLocation = new String[2];
myLocation = gps1.split(",");
src_lat = Double.parseDouble(myLocation[0]);
src_long = Double.parseDouble(myLocation[1]);
String[] myLocation1 = new String[2];
myLocation1 = gps2.split(",");
dest_lat = Double.parseDouble(myLocation1[0]);
dest_long = Double.parseDouble(myLocation1[1]);
FragmentManager myFragmentManager = getFragmentManager();
MapFragment myMapFragment = (MapFragment)myFragmentManager.findFragmentById(R.id.map);
myMap = myMapFragment.getMap();
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.activity_main, 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(Main2Activity.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(Main2Activity.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.RED);
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("&mode=transit&sensor=false®ion=fr");
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(Main2Activity.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;
}
}