我已经忙了很长时间，试图在HelloMapView上找到如何在地图上两个（GPS）点之间画一条线，但没有成功。
请问有人可以告诉我怎么做吗？
假设我使用扩展了MapView的HelloMapView。我需要使用覆盖层吗？如果需要，我需要重写覆盖层的onDraw()方法并在这里绘制一条线吗？实际上，我尝试过这些事情，但没有结果。
先谢谢你了！
在谷歌地图上绘制线路/路径
127
- mnish
1
4您可以重写MapView的onDraw方法（不要忘记调用父类的onDraw方法），但使用覆盖层会更清晰。也许您可以展示一下覆盖层类中的onDraw代码，这样我们就能看到发生了什么？ - Maurits Rijk
13个回答
119
感谢您的帮助。最终我能够在地图上画出一条线。 我的做法如下:
/** Called when the activity is first created. */
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 projection=mapv.getProjection();
projection.toPixels(gP1, p1);
projection.toPixels(gP2, p2);
path.moveTo(p2.x, p2.y);
path.lineTo(p1.x,p1.y);
canvas.drawPath(path, mPaint);
}
- mnish
8
24根据文档，draw() 方法会被调用两次——首先使用 shadow = true，允许 Overlay 绘制标记的阴影等内容，然后再次使用 shadow = false。因此，如果您的覆盖层没有阴影，当 shadow == true 时应该简单地返回并不进行绘制。 - Ridcully
3如果您添加更多的点以形成一个封闭区域，那么您可以绘制一个填充了Color.RED的多边形。 - user538565
@Satheesh 这可能与你膨胀 XML 布局文件时有关。也许当你尝试检索你的 MapView 时发生了错误。也许你有一个错误的 ID？ - StuStirling
另外，从draw()方法中删除不可变对象的创建将是一个很好的实践。 - Johnny Doe
5为了使用Overlay类，需要导入什么？ - beckah
显示剩余3条评论
59
对于那些真正只想画一条简单线的人，确实也有非常短的版本。
GoogleMap map;
// ... get a map.
// Add a thin red line from London to New York.
Polyline line = map.addPolyline(new PolylineOptions()
.add(new LatLng(51.5, -0.1), new LatLng(40.7, -74.0))
.width(5)
.color(Color.RED));
- Risadinha
3
2不需要 Polyline 线，谢谢，已经完美运行。 - Ben
这是必须的，并且很有用，因为如果您想同时只有一个，则需要删除先前创建的一个。 - luiscosta
1这对我有用。但如果我们需要获取最短路径，该如何实现呢？ - Dinith
21
// This Activity will draw a line between two selected points on Map
public class MainActivity extends MapActivity {
MapView myMapView = null;
MapController myMC = null;
GeoPoint geoPoint = null;
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
myMapView = (MapView) findViewById(R.id.mapview);
geoPoint = null;
myMapView.setSatellite(false);
String pairs[] = getDirectionData("ahmedabad", "vadodara");
String[] lngLat = pairs[0].split(",");
// STARTING POINT
GeoPoint startGP = new GeoPoint(
(int) (Double.parseDouble(lngLat[1]) * 1E6), (int) (Double
.parseDouble(lngLat[0]) * 1E6));
myMC = myMapView.getController();
geoPoint = startGP;
myMC.setCenter(geoPoint);
myMC.setZoom(15);
myMapView.getOverlays().add(new DirectionPathOverlay(startGP, startGP));
// NAVIGATE THE PATH
GeoPoint gp1;
GeoPoint gp2 = startGP;
for (int i = 1; i < pairs.length; i++) {
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));
myMapView.getOverlays().add(new DirectionPathOverlay(gp1, gp2));
Log.d("xxx", "pair:" + pairs[i]);
}
// END POINT
myMapView.getOverlays().add(new DirectionPathOverlay(gp2, gp2));
myMapView.getController().animateTo(startGP);
myMapView.setBuiltInZoomControls(true);
myMapView.displayZoomControls(true);
}
@Override
protected boolean isRouteDisplayed() {
// TODO Auto-generated method stub
return false;
}
private String[] getDirectionData(String srcPlace, String destPlace) {
String urlString = "http://maps.google.com/maps?f=d&hl=en&saddr="
+ srcPlace + "&daddr=" + destPlace
+ "&ie=UTF8&0&om=0&output=kml";
Log.d("URL", urlString);
Document doc = null;
HttpURLConnection urlConnection = null;
URL url = null;
String pathConent = "";
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());
} catch (Exception e) {
}
NodeList nl = doc.getElementsByTagName("LineString");
for (int s = 0; s < nl.getLength(); s++) {
Node rootNode = nl.item(s);
NodeList configItems = rootNode.getChildNodes();
for (int x = 0; x < configItems.getLength(); x++) {
Node lineStringNode = configItems.item(x);
NodeList path = lineStringNode.getChildNodes();
pathConent = path.item(0).getNodeValue();
}
}
String[] tempContent = pathConent.split(" ");
return tempContent;
}
}
//*****************************************************************************
DirectionPathOverlay
public class DirectionPathOverlay extends Overlay {
private GeoPoint gp1;
private GeoPoint gp2;
public DirectionPathOverlay(GeoPoint gp1, GeoPoint gp2) {
this.gp1 = gp1;
this.gp2 = gp2;
}
@Override
public boolean draw(Canvas canvas, MapView mapView, boolean shadow,
long when) {
// TODO Auto-generated method stub
Projection projection = mapView.getProjection();
if (shadow == false) {
Paint paint = new Paint();
paint.setAntiAlias(true);
Point point = new Point();
projection.toPixels(gp1, point);
paint.setColor(Color.BLUE);
Point point2 = new Point();
projection.toPixels(gp2, point2);
paint.setStrokeWidth(2);
canvas.drawLine((float) point.x, (float) point.y, (float) point2.x,
(float) point2.y, paint);
}
return super.draw(canvas, mapView, shadow, when);
}
@Override
public void draw(Canvas canvas, MapView mapView, boolean shadow) {
// TODO Auto-generated method stub
super.draw(canvas, mapView, shadow);
}
}
- richa123
3
1我一直在做类似的东西，扩展了Overlay但使用draw来在点之间画线。不同之处在于我使用GPS跟踪我的移动，每次找到一个新位置，就将其添加到ArrayList中，然后从ArrayList中最新的2个位置创建一个新的DirectionPathOverlay。我的问题是，除非我与地图交互，否则线条不会出现在地图上，例如如果我触摸屏幕并移动以平移地图，那么最后10秒钟的线条绘制将出现，有什么想法为什么它不会实时绘制而只有当我交互时才会出现？ - Infiniti Fizz
1@Infiniti：您应该将此作为新问题发布，而不是作为评论。 - Jonas
@richa123 我正在尝试你在这里解释的相同代码。但是我在这一行遇到了错误 String pairs[] = getDirectionData("ahmedabad", "vadodara"); 并且应用程序将会强制关闭。请问你能帮忙解决这个问题吗？ - KAREEM MAHAMMED
11
这也可以通过使用意图（intents）来实现：
final Intent intent = new Intent(Intent.ACTION_VIEW,
Uri.parse(
"http://maps.google.com/maps?" +
"saddr="+YOUR_START_LONGITUDE+","+YOUR_START_LATITUDE+"&daddr="YOUR_END_LONGITUDE+","+YOUR_END_LATITUDE));
intent.setClassName(
"com.google.android.apps.maps",
"com.google.android.maps.MapsActivity");
startActivity(intent);
- 0xC0DED00D
1
2在URL参数中，纬度应该放在经度之前。 - user606669
11
这是完整的源代码，用于从起点纬度和经度绘制方向路径到目的地纬度和经度。我已将上述代码更改为适用于纬度和经度而不是起点和目的地。 因此，任何通过GPS获取其纬度和经度的人都可以从其GPS设备获取到目的地坐标的方向。
由于以上答案，我们能够进行这样的更改并获得路径方向。
public class DrawMapActivity extends MapActivity {
MapView myMapView = null;
MapController myMC = null;
GeoPoint geoPoint = null;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
myMapView = (MapView) findViewById(R.id.mapview);
geoPoint = null;
myMapView.setSatellite(false);
double fromLat = 12.303534;
double fromLong = 76.64611;
double toLat = 12.9715987;
double toLong = 77.5945627;
String sourceLat = Double.toString(fromLat);
String sourceLong = Double.toString(fromLong);
String destinationLat = Double.toString(toLat);
String destinationLong = Double.toString(toLong);
String pairs[] = getDirectionData(sourceLat,sourceLong, destinationLat, destinationLong );
String[] lngLat = pairs[0].split(",");
// STARTING POINT
GeoPoint startGP = new GeoPoint((int) (Double.parseDouble(lngLat[1]) * 1E6), (int) (Double.parseDouble(lngLat[0]) * 1E6));
myMC = myMapView.getController();
geoPoint = startGP;
myMC.setCenter(geoPoint);
myMC.setZoom(10);
myMapView.getOverlays().add(new DirectionPathOverlay(startGP, startGP));
// NAVIGATE THE PATH
GeoPoint gp1;
GeoPoint gp2 = startGP;
for (int i = 1; i < pairs.length; i++) {
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));
myMapView.getOverlays().add(new DirectionPathOverlay(gp1, gp2));
Log.d("xxx", "pair:" + pairs[i]);
}
// END POINT
myMapView.getOverlays().add(new DirectionPathOverlay(gp2, gp2));
myMapView.getController().animateTo(startGP);
myMapView.setBuiltInZoomControls(true);
myMapView.displayZoomControls(true);
}
@Override
protected boolean isRouteDisplayed() {
// TODO Auto-generated method stub
return false;
}
private String[] getDirectionData(String sourceLat, String sourceLong, String destinationLat, String destinationLong) {
String urlString = "http://maps.google.com/maps?f=d&hl=en&" +"saddr="+sourceLat+","+sourceLong+"&daddr="+destinationLat+","+destinationLong + "&ie=UTF8&0&om=0&output=kml";
Log.d("URL", urlString);
Document doc = null;
HttpURLConnection urlConnection = null;
URL url = null;
String pathConent = "";
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());
} catch (Exception e) {
}
NodeList nl = doc.getElementsByTagName("LineString");
for (int s = 0; s < nl.getLength(); s++) {
Node rootNode = nl.item(s);
NodeList configItems = rootNode.getChildNodes();
for (int x = 0; x < configItems.getLength(); x++) {
Node lineStringNode = configItems.item(x);
NodeList path = lineStringNode.getChildNodes();
pathConent = path.item(0).getNodeValue();
}
}
String[] tempContent = pathConent.split(" ");
return tempContent;
}
}
//*****************************************************************************
class DirectionPathOverlay extends Overlay {
private GeoPoint gp1;
private GeoPoint gp2;
public DirectionPathOverlay(GeoPoint gp1, GeoPoint gp2) {
this.gp1 = gp1;
this.gp2 = gp2;
}
@Override
public boolean draw(Canvas canvas, MapView mapView, boolean shadow,
long when) {
// TODO Auto-generated method stub
Projection projection = mapView.getProjection();
if (shadow == false) {
Paint paint = new Paint();
paint.setAntiAlias(true);
Point point = new Point();
projection.toPixels(gp1, point);
paint.setColor(Color.BLUE);
Point point2 = new Point();
projection.toPixels(gp2, point2);
paint.setStrokeWidth(2);
canvas.drawLine((float) point.x, (float) point.y, (float) point2.x,(float) point2.y, paint);
}
return super.draw(canvas, mapView, shadow, when);
}
@Override
public void draw(Canvas canvas, MapView mapView, boolean shadow) {
// TODO Auto-generated method stub
super.draw(canvas, mapView, shadow);
}
}
- Mukunda
5
我正在尝试您在这里解释的相同代码。但是我在这一行遇到了错误 String pairs[] = getDirectionData("ahmedabad", "vadodara"); 并且应用程序将强制关闭。请问您能帮忙解决这个问题吗？ - KAREEM MAHAMMED
@KAREEMMAHAMMED 如果您能正确地查看我的上面的代码，我正在传递源和目的地地点的纬度和经度，而不是城市名称。richa123正在传递城市名称以获取两个城市之间的方向。谢谢。 - Mukunda
我按照你的代码尝试了一下，但是还是出现了相同的错误。在这一行代码 String pairs[] = getDirectionData(sourceLat,sourceLong, destinationLat, destinationLong ); 我遇到了强制关闭的情况。请问你能否给我发送一个示例代码？ - KAREEM MAHAMMED
@KAREEMMAHAMMED，请发布您的代码，包括布局和logcat详细信息。 - Mukunda
感谢您的回复。我已经在http://stackoverflow.com/questions/11895184/getting-issue-drawing-line-in-map-between-two-locations-in-android-sdk发布了代码和logcat详细信息。 - KAREEM MAHAMMED
6
使用Google Maps Android API v2非常简单
只需从开发者文档中复制示例即可
(当然，您需要先初始化地图)
GoogleMap map;
// ... get a map.
// Add a thin red line from London to New York.
Polyline line = map.addPolyline(new PolylineOptions()
.add(new LatLng(51.5, -0.1), new LatLng(40.7, -74.0))
.width(5)
.color(Color.RED));
- Thorsten Niehues
1
当您创建地图Activity（简单的Android Studio模板）时，您可以将此代码添加到地图Activity中的onMapReady方法中。 - ahmed_khan_89
4
是的，您需要使用覆盖层。
您需要获取MapView上的覆盖层，并将新的覆盖层添加到其中。
您的类继承自Overlay，这是一个透明的画布，在其上可以像其他画布一样进行绘制。
您可以使用mapView.getProjection()来获取地图视图的投影。
...
- ddcruver
1
我正在尝试你在这里解释的相同代码。但是我在这一行遇到了错误 String pairs[] = getDirectionData("ahmedabad", "vadodara"); 并且应用程序将会强制关闭。请问你能帮忙解决这个问题吗？ - KAREEM MAHAMMED
1
public class MainActivity extends FragmentActivity {
List<Overlay> mapOverlays;
GeoPoint point1, point2;
LocationManager locManager;
Drawable drawable;
Document document;
GMapV2GetRouteDirection v2GetRouteDirection;
LatLng fromPosition;
LatLng toPosition;
GoogleMap mGoogleMap;
MarkerOptions markerOptions;
Location location ;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
v2GetRouteDirection = new GMapV2GetRouteDirection();
SupportMapFragment supportMapFragment = (SupportMapFragment) getSupportFragmentManager()
.findFragmentById(R.id.map);
mGoogleMap = supportMapFragment.getMap();
// Enabling MyLocation in Google Map
mGoogleMap.setMyLocationEnabled(true);
mGoogleMap.getUiSettings().setZoomControlsEnabled(true);
mGoogleMap.getUiSettings().setCompassEnabled(true);
mGoogleMap.getUiSettings().setMyLocationButtonEnabled(true);
mGoogleMap.getUiSettings().setAllGesturesEnabled(true);
mGoogleMap.setTrafficEnabled(true);
mGoogleMap.animateCamera(CameraUpdateFactory.zoomTo(12));
markerOptions = new MarkerOptions();
fromPosition = new LatLng(11.663837, 78.147297);
toPosition = new LatLng(11.723512, 78.466287);
GetRouteTask getRoute = new GetRouteTask();
getRoute.execute();
}
/**
*
* @author VIJAYAKUMAR M
* This class Get Route on the map
*
*/
private class GetRouteTask extends AsyncTask<String, Void, String> {
private ProgressDialog Dialog;
String response = "";
@Override
protected void onPreExecute() {
Dialog = new ProgressDialog(MainActivity.this);
Dialog.setMessage("Loading route...");
Dialog.show();
}
@Override
protected String doInBackground(String... urls) {
//Get All Route values
document = v2GetRouteDirection.getDocument(fromPosition, toPosition, GMapV2GetRouteDirection.MODE_DRIVING);
response = "Success";
return response;
}
@Override
protected void onPostExecute(String result) {
mGoogleMap.clear();
if(response.equalsIgnoreCase("Success")){
ArrayList<LatLng> directionPoint = v2GetRouteDirection.getDirection(document);
PolylineOptions rectLine = new PolylineOptions().width(10).color(
Color.RED);
for (int i = 0; i < directionPoint.size(); i++) {
rectLine.add(directionPoint.get(i));
}
// Adding route on the map
mGoogleMap.addPolyline(rectLine);
markerOptions.position(toPosition);
markerOptions.draggable(true);
mGoogleMap.addMarker(markerOptions);
}
Dialog.dismiss();
}
}
@Override
protected void onStop() {
super.onStop();
finish();
}
}
路由助手类
public class GMapV2GetRouteDirection {
public final static String MODE_DRIVING = "driving";
public final static String MODE_WALKING = "walking";
public GMapV2GetRouteDirection() { }
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;
}
}
- Jigar Pandya
1
您可以从传递到draw()方法的MapView对象中获取投影：
mapv.getProjection().toPixels(gP1, p1);
- John J Smith
0
Try this one:
Add itemizedOverlay class:
public class AndroidGoogleMapsActivity extends MapActivity {
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
// Displaying Zooming controls
MapView mapView = (MapView) findViewById(R.id.mapview);
mapView.setBuiltInZoomControls(true);
MapController mc = mapView.getController();
double lat = Double.parseDouble("48.85827758964043");
double lon = Double.parseDouble("2.294543981552124");
GeoPoint geoPoint = new GeoPoint((int)(lat * 1E6), (int)(lon * 1E6));
mc.animateTo(geoPoint);
mc.setZoom(15);
mapView.invalidate();
/**
* Placing Marker
* */
List<Overlay> mapOverlays = mapView.getOverlays();
Drawable drawable = this.getResources().getDrawable(R.drawable.mark_red);
AddItemizedOverlay itemizedOverlay =
new AddItemizedOverlay(drawable, this);
OverlayItem overlayitem = new OverlayItem(geoPoint, "Hello", "Sample Overlay item");
itemizedOverlay.addOverlay(overlayitem);
mapOverlays.add(itemizedOverlay);
}
@Override
protected boolean isRouteDisplayed() {
return false;
}
}
- Hiren Patel
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