假设我在谷歌地图上有两个地理位置（点），现在我想突出显示这两个点在不同城市之间的最佳路线。我该怎么做？我在互联网上搜索了Drawing a line/path on Google Maps，但这解释了在两点之间划出一条直线。我需要找到连接不同城市的路线，至少是两点之间的地方。不是直线。任何人都可以给我一些好的教程或一些想法如何做到这一点？
答案：如果任何其他人遇到同样的问题，请查看接受的答案。要实现最佳路线，请参阅http://csie-tw.blogspot.com/2009/06/android-driving-direction-route-path.html这是一个包含工作代码的优秀教程。您可以根据需要对其进行修改。更多的事情，虽然测试请只给出那些路径可能的坐标（我正在做的错误）.Rest一切都很好。继续代码。谢谢。
答案 0 :(得分：1)
完成此代码。根据您的要求修改代码
//mapdirection.java
public class mapdirection extends MapActivity{
MapView mapview;
MapRouteOverlay mapoverlay;
Context _context;
List<Overlay> maplistoverlay;
Drawable drawable,drawable2;
MapOverlay mapoverlay2,mapoverlay3;
GeoPoint srcpoint,destpoint;
Overlay overlayitem;
public void onCreate(Bundle savedInstanceState){
super.onCreate(savedInstanceState);
requestWindowFeature(Window.FEATURE_NO_TITLE);
setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_PORTRAIT);
setContentView(R.layout.map_direction);
RegisterActivities.registerActivity(this);
mapview=(MapView)this.findViewById(R.id.mapview);
callMap();
}
private void callMap() {
srcpoint=new GeoPoint((int)(Data.src_lat_date*1E6),(int)(Data.src_long_data*1E6));
maplistoverlay=mapview.getOverlays();
drawable=this.getResources().getDrawable(R.drawable.green_a);
mapoverlay2=new MapOverlay(drawable);
OverlayItem overlayitem = new OverlayItem(srcpoint, "", "");
mapoverlay2.addOverlay(overlayitem);
maplistoverlay.add(mapoverlay2);
destpoint=new GeoPoint((int)(Data.dest_lat_data*1E6),(int)(Data.dest_long_data*1E6));
drawable2=this.getResources().getDrawable(R.drawable.green_b);
mapoverlay3=new MapOverlay(drawable2);
OverlayItem overlayitem3 = new OverlayItem(destpoint, "", "");
mapoverlay3.addOverlay(overlayitem3);
maplistoverlay.add(mapoverlay3);
double dest_lat = Data.dest_lat_data;
double dest_long = Data.dest_long_data;
GeoPoint srcGeoPoint = new GeoPoint((int) (Data.src_lat_date* 1E6),
(int) (Data.src_long_data * 1E6));
GeoPoint destGeoPoint = new GeoPoint((int) (dest_lat * 1E6),
(int) (dest_long * 1E6));
DrawPath(srcGeoPoint, destGeoPoint, Color.BLUE, mapview);
mapview.getController().animateTo(srcGeoPoint);
mapview.getController().setZoom(13);
//mapview.setStreetView(true);
mapview.setBuiltInZoomControls(true);
mapview.invalidate();
}
private void DrawPath(GeoPoint src, GeoPoint dest, int color,
MapView mMapView01) {
// connect to map web service
StringBuilder urlString = new StringBuilder();
urlString.append("http://maps.google.com/maps?f=d&hl=en");
urlString.append("&saddr=");//from
urlString.append( Double.toString((double)src.getLatitudeE6()/1.0E6 ));
urlString.append(",");
urlString.append( Double.toString((double)src.getLongitudeE6()/1.0E6 ));
urlString.append("&daddr=");//to
urlString.append( Double.toString((double)dest.getLatitudeE6()/1.0E6 ));
urlString.append(",");
urlString.append( Double.toString((double)dest.getLongitudeE6()/1.0E6 ));
urlString.append("&ie=UTF8&0&om=0&output=kml");
Log.d("xxx","URL="+urlString.toString());
//System.out.println(urlString);
// get the kml (XML) doc. And parse it to get the coordinates(direction route).
Document doc = null;
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 = db.parse(urlConnection.getInputStream());
if(doc.getElementsByTagName("GeometryCollection").getLength()>0)
{
//String path = doc.getElementsByTagName("GeometryCollection").item(0).getFirstChild().getFirstChild().getNodeName();
String path = doc.getElementsByTagName("GeometryCollection").item(0).getFirstChild().getFirstChild().getFirstChild().getNodeValue() ;
Log.d("xxx","path="+ path);
String [] pairs = path.split(" ");
String[] lngLat = pairs[0].split(","); // lngLat[0]=longitude lngLat[1]=latitude lngLat[2]=height
// src
GeoPoint startGP = new GeoPoint((int)(Double.parseDouble(lngLat[1])*1E6),(int)(Double.parseDouble(lngLat[0])*1E6));
//mMapView01.getOverlays().add(overlayitem);
GeoPoint gp1;
GeoPoint gp2 = startGP;
for(int i=1;i<pairs.length;i++) // the last one would be crash
{
lngLat = pairs[i].split(",");
gp1 = gp2;
// watch out! For GeoPoint, first:latitude, second:longitude
gp2 = new GeoPoint((int)(Double.parseDouble(lngLat[1])*1E6),(int)(Double.parseDouble(lngLat[0])*1E6));
mMapView01.getOverlays().add(new MapRouteOverlay(gp1,gp2,2,color));
Log.d("xxx","pair:" + pairs[i]);
}
//mMapView01.getOverlays().add(new MapRouteOverlay(dest,dest, 3)); // use the default color
}
}
catch (MalformedURLException e)
{
e.printStackTrace();
}
catch (IOException e)
{
e.printStackTrace();
}
catch (ParserConfigurationException e)
{
e.printStackTrace();
}
catch (SAXException e)
{
e.printStackTrace();
}
}
@Override
protected boolean isRouteDisplayed() {
// TODO Auto-generated method stub
return false;
}
//MapRouteOverlay.java
public class MapRouteOverlay extends Overlay {
private GeoPoint gp1;
private GeoPoint gp2;
private int mode=0;
private int defaultColor;
public MapRouteOverlay(GeoPoint gp1,GeoPoint gp2,int mode) // GeoPoint is a int. (6E)
{
this.gp1 = gp1;
this.gp2 = gp2;
this.mode = mode;
defaultColor = 999; // no defaultColor
}
public MapRouteOverlay(GeoPoint gp1,GeoPoint gp2,int mode, int defaultColor)
{
this.gp1 = gp1;
this.gp2 = gp2;
this.mode = mode;
this.defaultColor = defaultColor;
}
public int getMode()
{
return mode;
}
public boolean draw
(Canvas canvas, MapView mapView, boolean shadow, long when)
{
Projection projection = mapView.getProjection();
if (shadow == false)
{
Paint paint = new Paint();
paint.setAntiAlias(true);
Point point = new Point();
projection.toPixels(gp1, point);
if(mode==2)
{
if(defaultColor==999)
paint.setColor(Color.RED);
else
paint.setColor(defaultColor);
Point point2 = new Point();
projection.toPixels(gp2, point2);
paint.setStrokeWidth(5);
paint.setAlpha(120);
canvas.drawLine(point.x, point.y, point2.x,point2.y, paint);
}
}
return super.draw(canvas, mapView, shadow, when);
}
}
答案 1 :(得分：1)
是不是很久以后才回答这个问题的权利。但我认为这可以帮助其他任何人。
将此代码放在onCreate或您自己的方法中。
MapView mv = (MapView)findViewById(R.id.mvGoogle);
mv.setBuiltInZoomControls(true);
MapController mc = mv.getController();
//getDirections(lat1,lon2,lat2,lon2);
ArrayList<GeoPoint> all_geo_points = getDirections(10.154929, 76.390316, 10.015861, 76.341867);
if(all_geo_points.size()>0){
GeoPoint moveTo = all_geo_points.get(0);
mc.animateTo(moveTo);
mc.setZoom(12);
mv.getOverlays().add(new MyOverlay(all_geo_points));
}else {
Toast.makeText(getApplicationContext(), "Not able to show route !!", Toast.LENGTH_LONG).show();
}
现在制作自己的自定义叠加层。
public class MyOverlay extends Overlay {
private ArrayList<GeoPoint> all_geo_points;
public MyOverlay(ArrayList<GeoPoint> allGeoPoints) {
super();
this.all_geo_points = allGeoPoints;
}
@Override
public boolean draw(Canvas canvas, MapView mv, boolean shadow, long when) {
super.draw(canvas, mv, shadow);
drawPath(mv, canvas);
return true;
}
public void drawPath(MapView mv, Canvas canvas) {
int xPrev = -1, yPrev = -1, xNow = -1, yNow = -1;
Paint paint = new Paint();
paint.setColor(Color.BLUE);
paint.setStyle(Paint.Style.FILL_AND_STROKE);
paint.setStrokeWidth(4);
paint.setAlpha(100);
if (all_geo_points != null) for (int i = 0; i < all_geo_points.size() - 4; i++) {
GeoPoint gp = all_geo_points.get(i);
Point point = new Point();
mv.getProjection().toPixels(gp, point);
xNow = point.x;
yNow = point.y;
if (xPrev != -1) {
canvas.drawLine(xPrev, yPrev, xNow, yNow, paint);
}
xPrev = xNow;
yPrev = yNow;
}
}
}
现在这个方法将为您提供绘制路径的所有GeoPoints。我更愿意将此代码放在单独的AsyncTask中。
public static ArrayList<GeoPoint> getDirections(double lat1, double lon1, double lat2, double lon2) {
String url = "http://maps.googleapis.com/maps/api/directions/xml?origin=" + lat1 + "," + lon1 + "&destination=" + lat2 + "," + lon2
+ "&sensor=false&units=metric";
String tag[] = {"lat", "lng"};
ArrayList<GeoPoint> list_of_geopoints = new ArrayList<GeoPoint>();
HttpResponse response = null;
try {
HttpClient httpClient = new DefaultHttpClient();
HttpContext localContext = new BasicHttpContext();
HttpPost httpPost = new HttpPost(url);
response = httpClient.execute(httpPost, localContext);
InputStream in = response.getEntity().getContent();
DocumentBuilder builder = DocumentBuilderFactory.newInstance().newDocumentBuilder();
Document doc = builder.parse(in);
if (doc != null) {
NodeList nl1, nl2;
nl1 = doc.getElementsByTagName(tag[0]);
nl2 = doc.getElementsByTagName(tag[1]);
if (nl1.getLength() > 0) {
list_of_geopoints = new ArrayList<GeoPoint>();
for (int i = 0; i < nl1.getLength(); i++) {
Node node1 = nl1.item(i);
Node node2 = nl2.item(i);
double lat = Double.parseDouble(node1.getTextContent());
double lng = Double.parseDouble(node2.getTextContent());
list_of_geopoints.add(new GeoPoint((int) (lat * 1E6), (int) (lng * 1E6)));
}
} else {
// No points found
}
}
} catch (Exception e) {
e.printStackTrace();
}
return list_of_geopoints;
}
答案 2 :(得分：1)
此链接将为您提供帮助 http://iamvijayakumar.blogspot.in/2013/04/android-draw-route-between-two-geo.html?showComment=1380537294806#c9193038144229906059？ 检查一下......
答案 3 :(得分：0)
那样的东西？
http://blog.synyx.de/2010/06/routing-driving-directions-on-android-%E2%80%93-part-2-draw-the-route/
答案 4 :(得分：0)
假设您希望Google执行此工作，API的文档位于http://code.google.com/apis/maps/documentation/javascript/services.html#RenderingDirections（下拉“路线”设置.PC（与Android相对）示例位于http://maps.forum.nu/gm_driving_directions2.html 。