我想在Google地图上绘制一条路线，使用GPS改变我的位置。当我的位置发生变化时（创建新的地理位置时），点在谷歌地图上移动，但我无法在地图上绘制线条。
请帮助绘制谷歌地图上的路线。以下是我的代码
`
LocationManager locman;
LocationListener loclis;
Location location;
private MapView map;
List<GeoPoint> geoPointsArray = new ArrayList<GeoPoint>();
private MapController controller;
String provider = LocationManager.GPS_PROVIDER;
double lat;
double lon;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
initMapView();
initMyLocation();
locman = (LocationManager)getSystemService(Context.LOCATION_SERVICE);
//locman.requestLocationUpdates(provider,60000, 100,loclis);
//Location = locman.getLastKnownLocation(provider);
}
/** Find and initialize the map view. */
private void initMapView() {
map = (MapView) findViewById(R.id.mapView);
controller = map.getController();
map.setSatellite(false);
map.setBuiltInZoomControls(true);
}
/** Find Current Position on Map. */
private void initMyLocation() {
final MyLocationOverlay overlay = new MyLocationOverlay(this, map);
overlay.enableMyLocation();
overlay.enableCompass(); // does not work in emulator
overlay.runOnFirstFix(new Runnable() {
public void run() {
// Zoom in to current location
controller.setZoom(16);
controller.animateTo(overlay.getMyLocation());
}
});
map.getOverlays().add(overlay);
}
public void onLocationChanged(Location location) {
if (location != null){
lat = location.getLatitude();
lon = location.getLongitude();
GeoPoint New_geopoint = new GeoPoint((int)(lat*1e6),(int)(lon*1e6));
controller.animateTo(New_geopoint);
}
}
class MyOverlay extends Overlay{
public MyOverlay(){
}
public void draw(Canvas canvas, MapView mapv, boolean shadow){
super.draw(canvas, mapv, shadow);
Paint paint;
paint = new Paint();
paint.setColor(Color.GREEN);
paint.setAntiAlias(true);
paint.setStyle(Style.STROKE);
paint.setStrokeWidth(3);
Projection projection = map.getProjection();
Path p = new Path();
for (int i = 0; i < geoPointsArray.size(); i++) {
if (i == geoPointsArray.size() - 1) {
break;
}
Point from = new Point();
Point to = new Point();
projection.toPixels(geoPointsArray.get(i), from);
projection.toPixels(geoPointsArray.get(i + 1), to);
p.moveTo(from.x, from.y);
canvas.drawLine(from.x, from.y, to.x, to.y, paint);
//p.lineTo(to.x, to.y);
}
}
}
`
答案 0 :(得分：1)
为什么不画一条折线？你只需要LatLng实例。
var flightPlanCoordinates = [
new google.maps.LatLng(43.290307,-2.884174),
new google.maps.LatLng(41.3973,2.158964),
new google.maps.LatLng(40.462046,-3.809694),
new google.maps.LatLng(38.976895,-1.858366)
];
var flightPath = new google.maps.Polyline({
path: flightPlanCoordinates,
strokeColor: "#FF0000",
strokeOpacity: 1.0,
strokeWeight: 2
});
flightPath.setMap( map );
答案 1 :(得分：0)
我前段时间写过这段代码，原谅我，它可以清理很多，但我相信它应该做你需要的。
public class RouteSegmentOverlay extends Overlay {
private Paint paint;
private ArrayList<GeoPoint> routePoints;
private boolean routeIsActive;
private int numberRoutePoints;
private Path path;
// Constructor permitting the route array to be passed as an argument.
public RouteSegmentOverlay(ArrayList<GeoPoint> routePoints) {
this.routePoints = routePoints;
numberRoutePoints = routePoints.size();
routeIsActive = true;
}
// Method to turn route display on and off
public void setRouteView(boolean routeIsActive){
this.routeIsActive = routeIsActive;
}
public void setColor(int c){
color = c;
}
private int color = 0;
Paint.Style paintStyle = Paint.Style.STROKE;
public void setFillStyle(Paint.Style style){
paintStyle = style;
}
@Override
public void draw(Canvas canvas, MapView mapview, boolean shadow) {
super.draw(canvas, mapview, shadow);
if(! routeIsActive) return;
if(paint==null){
paint = new Paint();
paint.setAntiAlias(true);
paint.setStrokeWidth(7);
paint.setStyle(paintStyle);
paint.setAntiAlias(true);
paint.setARGB(255, 0, 0, 255);
paint.setColor(color);
}
if(bitmap==null){
wMin = Integer.MAX_VALUE;
wMax = Integer.MIN_VALUE;
hMin = Integer.MAX_VALUE;
hMax = Integer.MIN_VALUE;
lonMin = Integer.MAX_VALUE;
lonMax = Integer.MIN_VALUE;
latMin = Integer.MAX_VALUE;
latMax = Integer.MIN_VALUE;
Boolean newSegment = true;
Point pt = new Point();
GeoPoint point = null;
ArrayList<Point> points = new ArrayList<Point>();
for(int i=0; i<numberRoutePoints; i++){
point = routePoints.get(i);
int tempLat = point.getLatitudeE6();
int tempLon = point.getLongitudeE6();
if(tempLon<lonMin)lonMin = tempLon;
if(tempLon>lonMax)lonMax = tempLon;
if(tempLat<latMin)latMin = tempLat;
if(tempLat>latMax)latMax = tempLat;
mapview.getProjection().toPixels(routePoints.get(i), pt);
points.add(new Point(pt.x,pt.y));
if(pt.x<wMin)wMin = pt.x;
if(pt.x>wMax)wMax = pt.x;
if(pt.y<hMin)hMin = pt.y;
if(pt.y>hMax)hMax = pt.y;
}
topLeftIn = new GeoPoint(latMax, lonMin);
bottomRightIn = new GeoPoint(latMin, lonMax);
int width = (wMax-wMin);
int height = (hMax-hMin);
bitmap = Bitmap.createBitmap(width, height, Bitmap.Config.ARGB_4444);
Canvas c = new Canvas(bitmap);
Path bitmapPath = new Path();
bitmapPath.incReserve(numberRoutePoints);
newSegment = true;
for(Point p : points){
if (newSegment) {
bitmapPath.moveTo(p.x - wMin, p.y - hMin);
newSegment = false;
} else {
bitmapPath.lineTo(p.x - wMin, p.y - hMin);
}
}
c.drawPath(bitmapPath, paint);
}
mapview.getProjection().toPixels(topLeftIn, topLeftOut);
mapview.getProjection().toPixels(bottomRightIn, bottomRightOut);
int l = topLeftOut.x;
int t = topLeftOut.y;
int r = bottomRightOut.x;
int b = bottomRightOut.y;
Rect rect = new Rect(l,t,r,b);
canvas.drawBitmap(bitmap, new Rect(0,0,bitmap.getWidth(),bitmap.getHeight()),rect,null);
}
GeoPoint topLeftIn = null;
GeoPoint bottomRightIn = null;
Point topLeftOut = new Point();
Point bottomRightOut = new Point();
Bitmap bitmap = null;
int wMin = Integer.MAX_VALUE;
int wMax = 0;
int hMin = Integer.MAX_VALUE;
int hMax = 0;
int lonMin = Integer.MAX_VALUE;
int lonMax = 0;
int latMin = Integer.MAX_VALUE;
int latMax = 0;
}