java - 当前位置和搜索位置之间的道路/路线图

Question

这里是执行 2 点(origin, current location){geoPoint, "current Location"} 到 Destination.{geoPoint1, "Desti Location2"之间的道路路径或路线路径的代码}。它对我来说工作得很好。

我的问题是如何确定当前位置与搜索位置之间的道路。这里我是按钮搜索位置的 onClick ，它显示得很完美，但是我在引用--> {当前位置(scrgeoPoint)到搜索位置(destgeopointsearch)}<之间的路线图中出现错误.

有人有什么想法吗？

 //search button onclick
     mapLocationBtn = (Button) findViewById(R.id.locationbutton);
     mapLocationBtn.setVisibility(View.INVISIBLE);
     mapLocationBtn.setOnClickListener(new View.OnClickListener() {              
            @Override
            public void onClick(View v) {           
                String usrLoc = autoCompletetextView.getText().toString();
                Geocoder gc = new Geocoder(PlacesMapActivity.this);                 
                try {
                    addr=gc.getFromLocationName(usrLoc, 3);//maximum 2 results
                    if(addr.size()>0){
                        address=addr.get(0);//get the first result
                        convertLongi=address.getLongitude();
                        convertLati=address.getLatitude();
                        geopointsearch = new GeoPoint((int)(convertLati * 1E6), (int)(convertLongi * 1E6));                                     

                     // Map geopointsearch overlay item
                        itemizedOverlay2 = new AddItemizedOverlay(drawable_client, PlacesMapActivity.this);     
                        overlayitem = new OverlayItem(geopointsearch, "Your Location3", "R u Searching For me!");
                        itemizedOverlay2.addOverlay(overlayitem);       
                        mapOverlays.add(itemizedOverlay2);
                        itemizedOverlay2.populateNow();
                        mc.animateTo(geopointsearch);   
                     //   mc.zoomIn();
                    }                       
                } catch (IOException e) {                   
                    e.printStackTrace();
                }
            }                                   
        });

    // Map overlay item
    itemizedOverlay = new AddItemizedOverlay(drawable_user, this);
    overlayitem = new OverlayItem(geoPoint, "Your Location","That is you!");
    itemizedOverlay.addOverlay(overlayitem);        
    mapOverlays.add(itemizedOverlay);
    itemizedOverlay.populateNow();      
    // Map client overlay item
    itemizedOverlay1 = new AddItemizedOverlay(drawable_client, this);       
    overlayitem1 = new OverlayItem(geoPoint1, "Your Location2", "I am ur client!");
    itemizedOverlay1.addOverlay(overlayitem1);              
    mapOverlays.add(itemizedOverlay1);
    itemizedOverlay1.populateNow();
    // Map near overlay item    
    itemizedOverlay = new AddItemizedOverlay(drawable, this);

    mc = mapView.getController();

    // These values are used to get map boundary area
    // The area where you can see all the markers on screen
    int minLat = Integer.MAX_VALUE;
    int minLong = Integer.MAX_VALUE;
    int maxLat = Integer.MIN_VALUE;
    int maxLong = Integer.MIN_VALUE;

    // check for null in case it is null
    if (nearPlaces.results != null) {
        // loop through all the places
        for (Place place : nearPlaces.results) {
            latitude = place.geometry.location.lat; // latitude
            longitude = place.geometry.location.lng; // longitude

            // Geopoint to place on map
            geoPoin = new GeoPoint((int) (latitude * 1E6),
                    (int) (longitude * 1E6));

            // Map overlay item
            overlayitem = new OverlayItem(geoPoin, place.name,
                    place.vicinity);

            itemizedOverlay.addOverlay(overlayitem);

            // calculating map boundary area
            minLat  = (int) Math.min( geoPoin.getLatitudeE6(), minLat );
            minLong = (int) Math.min( geoPoin.getLongitudeE6(), minLong);
            maxLat  = (int) Math.max( geoPoin.getLatitudeE6(), maxLat );
            maxLong = (int) Math.max( geoPoin.getLongitudeE6(), maxLong );
        }
        mapOverlays.add(itemizedOverlay);

        // showing all overlay items
        itemizedOverlay.populateNow();
    }

    DrawPath(geoPoint, geoPoint1, geopointsearch, Color.GREEN, mapView);

    // Adjusting the zoom level so that you can see all the markers on map
    mapView.getController().zoomToSpan(Math.abs( minLat - maxLat ), Math.abs( minLong - maxLong ));

    // Showing the center of the map
    mc.animateTo(new GeoPoint((maxLat + minLat)/2, (maxLong + minLong)/2 ));
    mc.animateTo(geoPoint1);

    mapView.postInvalidate();

}   

private void DrawPath(GeoPoint scrgeoPoint, GeoPoint destgeoPoint, GeoPoint destgeopointsearch, int green, MapView mMapView) {
     HttpClient httpclient = new DefaultHttpClient();
        HttpPost httppost = new HttpPost(makeUrl(scrgeoPoint, destgeoPoint, destgeopointsearch));
        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);

            // calculate the distance between 2 point
            JSONArray legs = routes.getJSONArray("legs");
            Log.d("JSON","legs: "+legs.toString());
            JSONObject steps = legs.getJSONObject(0);
           Log.d("JSON","steps: "+steps.toString());
            JSONObject distance = steps.getJSONObject("distance");
            Log.d("JSON","distance: "+distance.toString());
            String sDistance = distance.getString("text");
            int iDistance = distance.getInt("value");                           
            distextView = (TextView) findViewById(R.id.distextView); 
            distextView.setText(distance.getString("text"));

            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) {            
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

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 scrgeoPoint, GeoPoint destgeoPoint, GeoPoint destgeopointsearch) {
    StringBuilder urlString = new StringBuilder();

    //Origin
    urlString.append("http://maps.googleapis.com/maps/api/directions/json");
    urlString.append("?origin=");// from
    urlString.append(Double.toString((double) scrgeoPoint.getLatitudeE6() / 1.0E6));
    urlString.append(",");
    urlString.append(Double.toString((double) scrgeoPoint.getLongitudeE6() / 1.0E6));
    //Destination
    urlString.append("&destination=");// to
    urlString.append(Double.toString((double) destgeoPoint.getLatitudeE6() / 1.0E6));
    urlString.append(",");
    urlString.append(Double.toString((double) destgeoPoint.getLongitudeE6() / 1.0E6));
    //search location
    urlString.append("&destination=");// to
    urlString.append(Double.toString((double) destgeopointsearch.getLatitudeE6() / 1.0E6));
    urlString.append(",");
    urlString.append(Double.toString((double) destgeopointsearch.getLongitudeE6() / 1.0E6));


    urlString.append("&mode=walking&sensor=true");             
    Log.d("xxx", "URL=" + urlString.toString());
    return urlString.toString();
}

Answer 1

据我了解，您需要保存您的位置和目的地，然后向 Google 询问方向，可能是这样的:

Intent intent = new Intent(android.content.Intent.ACTION_VIEW, 
Uri.parse("http://maps.google.com/maps?saddr=20.344,34.34&daddr=20.5666,45.345"));
startActivity(intent);

(摘自 this 帖子。)

然后你需要在许多点之间画一条线/路径(从Google收到)，以便在不穿过建筑物和角落的情况下实现路径。也许这段代码会对您有所启发:

private List<Overlay> mapOverlays;

private Projection projection;  

@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);

linearLayout = (LinearLayout) findViewById(R.id.zoomview);
mapView = (MapView) findViewById(R.id.mapview);
mapView.setBuiltInZoomControls(true);

mapOverlays = mapView.getOverlays();        
projection = mapView.getProjection();
mapOverlays.add(new MyOverlay());        

}

@Override
protected boolean isRouteDisplayed() {
return false;
}

class MyOverlay extends Overlay{

public MyOverlay(){

}   

public void draw(Canvas canvas, MapView mapv, boolean shadow){
    super.draw(canvas, mapv, shadow);

    Paint   mPaint = new Paint();
    mPaint.setDither(true);
    mPaint.setColor(Color.RED);
    mPaint.setStyle(Paint.Style.FILL_AND_STROKE);
    mPaint.setStrokeJoin(Paint.Join.ROUND);
    mPaint.setStrokeCap(Paint.Cap.ROUND);
    mPaint.setStrokeWidth(2);

    GeoPoint gP1 = new GeoPoint(19240000,-99120000);
    GeoPoint gP2 = new GeoPoint(37423157, -122085008);

    Point p1 = new Point();
    Point p2 = new Point();
    Path path = new Path();

    projection.toPixels(gP1, p1);
    projection.toPixels(gP2, p2);

    path.moveTo(p2.x, p2.y);
    path.lineTo(p1.x,p1.y);

    canvas.drawPath(path, mPaint);
}

(摘自 this 帖子。)