Google 改变了一些东西，现在是 shows major turns only。但是当使用 JSON 时，它会正确显示路径：
public class DrivingDirectionActivity extends MapActivity {
Point p1 = new Point();
Point p2 = new Point();
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
MapView mapView = (MapView) findViewById(R.id.map);
// setting a default value
double src_lat = 18.5535;
double src_long = 73.7966;
double dest_lat = 18.5535;
double dest_long = 73.7966;
Geocoder coder = new Geocoder(getApplicationContext(),
Locale.getDefault());
List<Address> address_src = null;
List<Address> address_dest = null;
try {
address_src = coder
.getFromLocationName(
"Deepmala Housing Complex, Pimple Saudagar, Pimpri Chinchwad",
1);
if (address_src.size() > 0) {
Address loc = address_src.get(0);
src_lat = loc.getLatitude();
src_long = loc.getLongitude();
}
} catch (IOException e) { // TODO Auto-generated catch block
e.printStackTrace();
}
try {
address_dest = coder.getFromLocationName(
"Infosys Phase 2, Hinjewadi Phase II, Hinjewadi", 1);
if (address_dest.size() > 0) {
Address loc = address_dest.get(0);
dest_lat = loc.getLatitude();
dest_long = loc.getLongitude();
}
} catch (IOException e) { // TODO Auto-generated catch block
e.printStackTrace();
}
mapView.setBuiltInZoomControls(true);
GeoPoint srcGeoPoint = new GeoPoint((int) (src_lat * 1E6),
(int) (src_long * 1E6));
GeoPoint destGeoPoint = new GeoPoint((int) (dest_lat * 1E6),
(int) (dest_long * 1E6));
DrawPath(srcGeoPoint, destGeoPoint, Color.GREEN, mapView);
mapView.getController().animateTo(srcGeoPoint);
mapView.getController().setZoom(13);
}
protected boolean isRouteDisplayed() {
// TODO Auto-generated method stub
return false;
}
private void DrawPath(GeoPoint src, GeoPoint dest, int color,
MapView mMapView) {
// connect to map web service
HttpClient httpclient = new DefaultHttpClient();
HttpPost httppost = new HttpPost(makeUrl(src, dest));
HttpResponse response;
try {
response = httpclient.execute(httppost);
HttpEntity entity = response.getEntity();
InputStream is = null;
is = entity.getContent();
BufferedReader reader = new BufferedReader(new InputStreamReader(
is, "iso-8859-1"), 8);
StringBuilder sb = new StringBuilder();
sb.append(reader.readLine() + "\n");
String line = "0";
while ((line = reader.readLine()) != null) {
sb.append(line + "\n");
}
is.close();
reader.close();
String result = sb.toString();
JSONObject jsonObject = new JSONObject(result);
JSONArray routeArray = jsonObject.getJSONArray("routes");
JSONObject routes = routeArray.getJSONObject(0);
JSONObject overviewPolylines = routes
.getJSONObject("overview_polyline");
String encodedString = overviewPolylines.getString("points");
List<GeoPoint> pointToDraw = decodePoly(encodedString);
mMapView.getOverlays().add(new MyOverLay(pointToDraw));
} catch (ClientProtocolException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (Exception e) {
e.printStackTrace();
// TODO: handle exception
}
}
private List<GeoPoint> decodePoly(String encoded) {
List<GeoPoint> poly = new ArrayList<GeoPoint>();
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;
GeoPoint p = new GeoPoint((int) (((double) lat / 1E5) * 1E6),
(int) (((double) lng / 1E5) * 1E6));
poly.add(p);
}
return poly;
}
private String makeUrl(GeoPoint src, GeoPoint dest) {
// TODO Auto-generated method stub
StringBuilder urlString = new StringBuilder();
urlString.append("http://maps.googleapis.com/maps/api/directions/json");
urlString.append("?origin=");// from
urlString.append(Double.toString((double) src.getLatitudeE6() / 1.0E6));
urlString.append(",");
urlString
.append(Double.toString((double) src.getLongitudeE6() / 1.0E6));
urlString.append("&destination=");// to
urlString
.append(Double.toString((double) dest.getLatitudeE6() / 1.0E6));
urlString.append(",");
urlString
.append(Double.toString((double) dest.getLongitudeE6() / 1.0E6));
urlString.append("&sensor=false");
Log.d("xxx", "URL=" + urlString.toString());
return urlString.toString();
}
class MyOverLay extends Overlay {
private int pathColor;
private final List<GeoPoint> points;
private boolean drawStartEnd;
public MyOverLay(List<GeoPoint> pointToDraw) {
// TODO Auto-generated constructor stub
this(pointToDraw, Color.GREEN, true);
}
public MyOverLay(List<GeoPoint> points, int pathColor,
boolean drawStartEnd) {
this.points = points;
this.pathColor = pathColor;
this.drawStartEnd = drawStartEnd;
}
private void drawOval(Canvas canvas, Paint paint, Point point) {
Paint ovalPaint = new Paint(paint);
ovalPaint.setStyle(Paint.Style.FILL_AND_STROKE);
ovalPaint.setStrokeWidth(2);
ovalPaint.setColor(Color.BLUE);
int _radius = 6;
RectF oval = new RectF(point.x - _radius, point.y - _radius,
point.x + _radius, point.y + _radius);
canvas.drawOval(oval, ovalPaint);
}
public boolean draw(Canvas canvas, MapView mapView, boolean shadow,
long when) {
Projection projection = mapView.getProjection();
if (shadow == false && points != null) {
Point startPoint = null, endPoint = null;
Path path = new Path();
// We are creating the path
for (int i = 0; i < points.size(); i++) {
GeoPoint gPointA = points.get(i);
Point pointA = new Point();
projection.toPixels(gPointA, pointA);
if (i == 0) { // This is the start point
startPoint = pointA;
path.moveTo(pointA.x, pointA.y);
} else {
if (i == points.size() - 1)// This is the end point
endPoint = pointA;
path.lineTo(pointA.x, pointA.y);
}
}
Paint paint = new Paint();
paint.setAntiAlias(true);
paint.setColor(pathColor);
paint.setStyle(Paint.Style.STROKE);
paint.setStrokeWidth(5);
paint.setAlpha(90);
if (getDrawStartEnd()) {
if (startPoint != null) {
drawOval(canvas, paint, startPoint);
}
if (endPoint != null) {
drawOval(canvas, paint, endPoint);
}
}
if (!path.isEmpty())
canvas.drawPath(path, paint);
}
return super.draw(canvas, mapView, shadow, when);
}
public boolean getDrawStartEnd() {
return drawStartEnd;
}
public void setDrawStartEnd(boolean markStartEnd) {
drawStartEnd = markStartEnd;
}
}
}