ini adalah snippet pada coding pemanggilan asynctask android maps
public class Request_Update extends AsyncTask<Location, Void, Location>{
@Override
protected void onPreExecute()
{
//Toast.makeText(getApplicationContext(), "onPreExecute()!", Toast.LENGTH_SHORT).show();
}
@Override
protected Location doInBackground(Location... location) {
// TODO Auto-generated method stub
String url = "http://maps.googleapis.com/maps/api/directions/xml?"
+ "origin=" + location[0].getLatitude() + "," + location[0].getLongitude()
+ "&destination=" + frnd_lat + "," + frnd_longi
+ "&sensor=false&units=metric&mode="+direction; //direction="walking" or "driving"
try {
HttpClient httpClient = new DefaultHttpClient();
HttpContext localContext = new BasicHttpContext();
HttpPost httpPost = new HttpPost(url);
HttpResponse response = httpClient.execute(httpPost, localContext);
InputStream in = response.getEntity().getContent();
DocumentBuilder builder = DocumentBuilderFactory.newInstance().newDocumentBuilder();
doc = builder.parse(in);
} catch (Exception e) {
}
return location[0];
}
@Override
protected void onPostExecute(Location location)
{
if(doc!=null)
{
directionPoint=getDirection(doc);
int ii = 0;
size_of_latlong=directionPoint.size();
for( ; ii <size_of_latlong ; ii++) {
if(ii==0)
{
PolylineOptions rectLine = new PolylineOptions().width(8).color(Color.RED);
rectLine.add(my_latlong,directionPoint.get(ii));
Polyline polyline=map.addPolyline(rectLine);
polylines.add(polyline);
}
else
{
PolylineOptions rectLine = new PolylineOptions().width(8).color(Color.RED);
rectLine.add(directionPoint.get(ii-1),directionPoint.get(ii));
Polyline polyline=map.addPolyline(rectLine);
polylines.add(polyline);
}
}
PolylineOptions rectLine = new PolylineOptions().width(8).color(Color.RED);
rectLine.add(frnd_latlong,directionPoint.get(ii-1));
Polyline polyline=map.addPolyline(rectLine);
polylines.add(polyline);
//map.addPolyline(rectLine);
}
}
}
public ArrayList<LatLng> getDirection(Document doc) {
NodeList nl1, nl2, nl3;
ArrayList<LatLng> listGeopoints = new ArrayList<LatLng>();
nl1 = doc.getElementsByTagName("step");
if (nl1.getLength() > 0) {
for (int i = 0; i < nl1.getLength(); i++) {
Node node1 = nl1.item(i);
nl2 = node1.getChildNodes();
Node locationNode = nl2.item(getNodeIndex(nl2, "start_location"));
nl3 = locationNode.getChildNodes();
Node latNode = nl3.item(getNodeIndex(nl3, "lat"));
double lat = Double.parseDouble(latNode.getTextContent());
Node lngNode = nl3.item(getNodeIndex(nl3, "lng"));
double lng = Double.parseDouble(lngNode.getTextContent());
listGeopoints.add(new LatLng(lat, lng));
locationNode = nl2.item(getNodeIndex(nl2, "polyline"));
nl3 = locationNode.getChildNodes();
latNode = nl3.item(getNodeIndex(nl3, "points"));
ArrayList<LatLng> arr = decodePoly(latNode.getTextContent());
for(int j = 0 ; j < arr.size() ; j++) {
listGeopoints.add(new LatLng(arr.get(j).latitude, arr.get(j).longitude));
}
locationNode = nl2.item(getNodeIndex(nl2, "end_location"));
nl3 = locationNode.getChildNodes();
latNode = nl3.item(getNodeIndex(nl3, "lat"));
lat = Double.parseDouble(latNode.getTextContent());
lngNode = nl3.item(getNodeIndex(nl3, "lng"));
lng = Double.parseDouble(lngNode.getTextContent());
listGeopoints.add(new LatLng(lat, lng));
}
}
return listGeopoints;
}
private int getNodeIndex(NodeList nl, String nodename) {
for(int i = 0 ; i < nl.getLength() ; i++) {
if(nl.item(i).getNodeName().equals(nodename))
return i;
}
return -1;
}
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;
}
