Belajar Android Menampilkan Direction dengan GoogleMaps Android V2

Pada Tutorial sebelumnya kita sudah membahas tentang menampilkan Map dan Marker dengan menggunakan GoogleMaps Api V2. Sekarang yang sudah banyak ditunggunih oleh para pembaca yaitu menampilkan direction dengan menggunakan GoogleMaps android V2.

Oke kita mulai saja

1. Buka lagi project PetaLokasi

2. Buat Class baru dengan nama GoogleMapV2Direction.java lalu ketikan kode berikut.

package net.agusharyanto.petalokasi;

import java.io.InputStream;
import java.util.ArrayList;

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

import org.apache.http.HttpResponse;
import org.apache.http.client.HttpClient;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.impl.client.DefaultHttpClient;
import org.apache.http.protocol.BasicHttpContext;
import org.apache.http.protocol.HttpContext;
import org.w3c.dom.Document;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;

import android.util.Log;

import com.google.android.gms.maps.model.LatLng;

public class GoogleMapV2Direction {
	public final static String MODE_DRIVING = "driving";
	public final static String MODE_WALKING = "walking";

	public GoogleMapV2Direction() { }

	public Document getDocument(LatLng start, LatLng end, String mode) {
		String url = "http://maps.googleapis.com/maps/api/directions/xml?"
        		+ "origin=" + start.latitude + "," + start.longitude
        		+ "&destination=" + end.latitude + "," + end.longitude
        		+ "&sensor=false&units=metric&mode=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();
            Document doc = builder.parse(in);
            return doc;
        } catch (Exception e) {
            e.printStackTrace();
        }
		return null;
	}

	public String getDurationText (Document doc) {
		NodeList nl1 = doc.getElementsByTagName("duration");
        Node node1 = nl1.item(0);
        NodeList nl2 = node1.getChildNodes();
        Node node2 = nl2.item(getNodeIndex(nl2, "text"));
        Log.i("DurationText", node2.getTextContent());
		return node2.getTextContent();
	}

	public int getDurationValue (Document doc) {
		NodeList nl1 = doc.getElementsByTagName("duration");
        Node node1 = nl1.item(0);
        NodeList nl2 = node1.getChildNodes();
        Node node2 = nl2.item(getNodeIndex(nl2, "value"));
        Log.i("DurationValue", node2.getTextContent());
		return Integer.parseInt(node2.getTextContent());
	}

	public String getDistanceText (Document doc) {
		NodeList nl1 = doc.getElementsByTagName("distance");
        Node node1 = nl1.item(0);
        NodeList nl2 = node1.getChildNodes();
        Node node2 = nl2.item(getNodeIndex(nl2, "text"));
        Log.i("DistanceText", node2.getTextContent());
		return node2.getTextContent();
	}

	public int getDistanceValue (Document doc) {
		NodeList nl1 = doc.getElementsByTagName("distance");
        Node node1 = nl1.item(0);
        NodeList nl2 = node1.getChildNodes();
        Node node2 = nl2.item(getNodeIndex(nl2, "value"));
        Log.i("DistanceValue", node2.getTextContent());
		return Integer.parseInt(node2.getTextContent());
	}

	public String getStartAddress (Document doc) {
		NodeList nl1 = doc.getElementsByTagName("start_address");
        Node node1 = nl1.item(0);
        Log.i("StartAddress", node1.getTextContent());
		return node1.getTextContent();
	}

	public String getEndAddress (Document doc) {
		NodeList nl1 = doc.getElementsByTagName("end_address");
        Node node1 = nl1.item(0);
        Log.i("StartAddress", node1.getTextContent());
		return node1.getTextContent();
	}

	public String getCopyRights (Document doc) {
		NodeList nl1 = doc.getElementsByTagName("copyrights");
        Node node1 = nl1.item(0);
        Log.i("CopyRights", node1.getTextContent());
		return node1.getTextContent();
	}

	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;
	}
}

Class inilah yang mengirim request ke server google dan mengolah responsenya untuk mengenerate direction dari dua buah titik yang kita kirimkan.

3. Edit Class MainActivity.java lalu ketikan kode berikut

package net.agusharyanto.petalokasi;

import java.util.ArrayList;

import org.w3c.dom.Document;

import android.app.Activity;
import android.graphics.Color;
import android.os.AsyncTask;
import android.os.Bundle;

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;

public class MainActivity extends Activity {
	GoogleMap mMap;
	GoogleMapV2Direction md;

	public void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.activity_main);
		LatLng fromPosition = new LatLng(-6.3039, 106.8267);
		LatLng toPosition = new LatLng(-6.29436, 106.8859);
		md = new GoogleMapV2Direction();
		mMap = ((MapFragment) getFragmentManager().findFragmentById(R.id.map))
				.getMap();

		LatLng coordinates = new LatLng(-6.3039, 106.8267);
		mMap.animateCamera(CameraUpdateFactory.newLatLngZoom(coordinates, 11));

		mMap.addMarker(new MarkerOptions().position(fromPosition)
				.title("Start"));
		mMap.addMarker(new MarkerOptions().position(toPosition).title("End"));
		getDirectionMap(fromPosition, toPosition);

	}

	private void getDirectionMap(LatLng from, LatLng to) {
		LatLng fromto[] = { from, to };
		new LongOperation().execute(fromto);
	}

	private class LongOperation extends AsyncTask<LatLng, Void, Document> {

		@Override
		protected Document doInBackground(LatLng... params) {
			Document doc = md.getDocument(params[0], params[1],
					GoogleMapV2Direction.MODE_DRIVING);
			return doc;
		}

		@Override
		protected void onPostExecute(Document result) {
			setResult(result);

		}

		@Override
		protected void onPreExecute() {

		}

		@Override
		protected void onProgressUpdate(Void... values) {
		}
	}

	public void setResult(Document doc) {
		int duration = md.getDurationValue(doc);
		String distance = md.getDistanceText(doc);
		String start_address = md.getStartAddress(doc);
		String copy_right = md.getCopyRights(doc);

		ArrayList<LatLng> directionPoint = md.getDirection(doc);
		PolylineOptions rectLine = new PolylineOptions().width(3).color(
				Color.RED);

		for (int i = 0; i < directionPoint.size(); i++) {
			rectLine.add(directionPoint.get(i));
		}

		mMap.addPolyline(rectLine);
	}

}

Pada method onCreate, kita deklarasikan dan set nilai lokasi Sumber (fromPosition) dan lokasi tujuan (toPosition). Nilai lokasi ini kita kirim ke method getDirectionMap dari sini kita gunakan asynctask untuk eksekusi method getDocument pada class GoogleMapV2Direction, method ini akan mengembalikan Nilai dalam type data Document. Nah Di nilai yang dikirim inilah terdapat nilai seperti distance (jarak) dan kumpulan titik directionya.

4. Saatnya kita lihat hasil kerja kita dengan me run projectnya.

Oh ia insya Allah tanggal 18 Mei nanti saya akan mengisi WorkShop Android di Politeknik Indramayu.

Bagi yang mau ikut bisa menghubungi panitia disana.

Semoga Bermanfaat

Salam Hangat

Agus Haryanto

referensi

http://stackoverflow.com