我目前正在开发谷歌地图应用程序，我可以显示两个给定（用户）点之间的路线，现在我试图为用户显示一些信息，如：持续时间在两点和距离之间以及显示替代道路。
搜索后我发现我可以在网址中添加内容，例如mode，alternatives = true ...
public class MapsActivity extends FragmentActivity {
private GoogleMap gm;
String Depart;
String Arrive;
TextView tvdirections;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_maps);
setUpMapifNeeded();
ImageButton serch_button = (ImageButton) findViewById(R.id.btnSearch);
tvdirections=(TextView)findViewById(R.id.tvdirections);
serch_button.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
final Dialog dialog_button = new Dialog(MapsActivity.this);
dialog_button.setTitle("Voir itineraires");
dialog_button.setContentView(R.layout.dialog);
dialog_button.show();
final EditText edittxt1 = (EditText) dialog_button.findViewById(R.id.depart);
final EditText edittxt2 = (EditText) dialog_button.findViewById(R.id.arrive);
Button GoButton = (Button) dialog_button.findViewById(R.id.btnDialog);
GoButton.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
Depart = edittxt1.getText().toString();
Arrive = edittxt2.getText().toString();
if ((Depart.equals("") || Arrive.equals("")) || (Depart.equals(null) || Arrive.equals(null))) {
Toast.makeText(getApplicationContext(), "Veuillez entrer les points de depart et d'arrive", Toast.LENGTH_SHORT).show();
} else {
new ItineraryActivity(getApplicationContext(), gm, Depart, Arrive,tvdirections).execute();
dialog_button.cancel();
gm.clear();
}
}
});
}
});
}
@Override
protected void onResume() {
super.onResume();
setUpMapifNeeded();
}
public void OnChangeToHybrid(View view) {
gm.setMapType(GoogleMap.MAP_TYPE_HYBRID);
}
public void OnChangeToNormal(View view) {
gm.setMapType(GoogleMap.MAP_TYPE_NORMAL);
}
private void setUpMapifNeeded() {
if (gm == null) {
gm = ((SupportMapFragment) getSupportFragmentManager().findFragmentById(R.id.mymap)).getMap();
}
if (gm != null) {
setUpMap();
}
}
private void setUpMap() {
//gm.addMarker(new MarkerOptions().position(new LatLng(0, 0)).title("hi bouchra :)"));
//gm.moveCamera(CameraUpdateFactory.newLatLngZoom(new LatLng(0, 0), 18));
gm.setMyLocationEnabled(true);
gm.getUiSettings().setZoomControlsEnabled(true);
gm.getUiSettings().setCompassEnabled(true);
}
}
这是另一个班级
public class ItineraryActivity extends AsyncTask<Void,Integer,Boolean> {
private static final String TOAST_ERR_MAJ = "Impossible de trouver un itineraire";
private Context context;
private GoogleMap gm;
private String Depart;
private String Arrive;
private TextView tvdirections;
private final ArrayList<LatLng> lstLatLng = new ArrayList<LatLng>();
private NodeList nl1;
private NodeList nl2;
private Node node1=null;
private Node node2=null;
public ItineraryActivity(final Context context, final GoogleMap gMap, final String Depart, final String Arrive, final TextView tvdirections) {
this.context = context;
this.gm = gMap;
this.Depart = Depart;
this.Arrive = Arrive;
this.tvdirections = tvdirections;
//nl1 = null;
}
@Override
protected void onPreExecute() {
}
@Override
public Boolean doInBackground(Void... params) {
try {
//Construction de l'url a appeler
final StringBuilder url = new StringBuilder("http://maps.googleapis.com/maps/api/directions/xml?sensor=false");
url.append("&origin=");
url.append(Depart.replace(' ', '+'));
url.append("&destination=");
url.append(Arrive.replace(' ', '+'));
url.append("&alternatives=true&units=metric");
final InputStream stream = new URL(url.toString()).openStream();
final DocumentBuilderFactory documentBuilderFactory = DocumentBuilderFactory.newInstance();
documentBuilderFactory.setIgnoringComments(true);
final DocumentBuilder documentBuilder = documentBuilderFactory.newDocumentBuilder();
final Document document = documentBuilder.parse(stream);
document.getDocumentElement().normalize();
final String status = document.getElementsByTagName("status").item(0).getTextContent();
if (!"OK".equals(status)) {
return false;
}
//On recupere les steps
final Element elementLeg = (Element) document.getElementsByTagName("leg").item(0);
final NodeList nodeListStep = elementLeg.getElementsByTagName("step");
final int length = nodeListStep.getLength();
//final NodeList distancelist= elementLeg.getElementsByTagName("distance");
for (int i = 0; i < length; i++) {
final Node nodeStep = nodeListStep.item(i);
if (nodeStep.getNodeType() == Node.ELEMENT_NODE) {
final Element elementStep = (Element) nodeStep;
//On decode les points du XML
decodePolylines(elementStep.getElementsByTagName("points").item(0).getTextContent());
}
}
nl1= document.getElementsByTagName("distance");
node1=nl1.item(0);
nl2=node1.getChildNodes();
node2=nl2.item(getNodeIndex(nl2, "text"));
return true;
} catch (final Exception e) {
return false;
}
}
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 void decodePolylines(final String encodedPoints) {
int index = 0;
int lat = 0, lng = 0;
while (index < encodedPoints.length()) {
int b, shift = 0, result = 0;
do {
b = encodedPoints.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 = encodedPoints.charAt(index++) - 63;
result |= (b & 0x1f) << shift;
shift += 5;
} while (b >= 0x20);
int dlng = ((result & 1) != 0 ? ~(result >> 1) : (result >> 1));
lng += dlng;
lstLatLng.add(new LatLng((double) lat / 1E5, (double) lng / 1E5));
}
}
//List<HashMap<String, String>> path = result.get(i);
protected void onPostExecute( final Boolean result) {
/*String distance = "";
String duration = "";*/
if (!result) {
Toast.makeText(context, TOAST_ERR_MAJ, Toast.LENGTH_SHORT).show();
} else {
final PolylineOptions polylines = new PolylineOptions();
polylines.color(Color.BLUE);
polylines.width(3);
//On construit le polyline
for (final LatLng latLng : lstLatLng) {
polylines.add(latLng);
}
final MarkerOptions markerA = new MarkerOptions();
markerA.position(lstLatLng.get(0));
markerA.icon(BitmapDescriptorFactory.defaultMarker(BitmapDescriptorFactory.HUE_GREEN));
final MarkerOptions markerB = new MarkerOptions();
markerB.position(lstLatLng.get(lstLatLng.size() - 1));
markerB.icon(BitmapDescriptorFactory.defaultMarker(BitmapDescriptorFactory.HUE_RED));
gm.moveCamera(CameraUpdateFactory.newLatLngZoom(lstLatLng.get(0), 10));
gm.addMarker(markerA);
gm.addPolyline(polylines);
gm.addMarker(markerB);
tvdirections.setText(""+node2);
}
}
答案 0 :(得分：1)
使用 JSON ：
这个例子被认为只能获取一条路线的数据，但为了使用更多的选项，你应该知道的唯一事情就是每条路线都有一个“腿”JSONArray。
final String str = "http://maps.googleapis.com/maps/api/directions/json?"
+ "origin=" + Start.latitude + "," + Start.longitude
+ "&destination=" + End.latitude + "," + End.longitude
+"&language=" +getResources().getConfiguration().locale.getDefault().getLanguage()
+ "&sensor=false&units=metric&mode=" + "walking"
+ "&alternatives=true";
URL url = new URL(str);
HttpURLConnection conn =(HttpURLConnection) url.openConnection();
InputStreamReader in = new InputStreamReader(conn.getInputStream());
StringBuilder jsonResults = new StringBuilder();
int read;
char[] buff = new char[1024];
while ((read = in.read(buff)) != -1) {
jsonResults.append(buff, 0, read);
}
JSONObject jsonObj = new JSONObject(jsonResults.toString());
JSONArray parentArray = jsonObj.getJSONArray("routes");
final JSONArray legArray = parentArray.getJSONObject(0).getJSONArray("legs");
//Distance
JSONObject distanceObj = legArray.getJSONObject(0).getJSONObject("distance");
distance = distanceObj.getInt("value"); //Value of distance
distance = distanceObj.getString("text"); //String that contains the distance value formated
//With duration is the same changing getJSONObject("distance") with getJSONObject("duration")