问题
i have a situation in my app where i should move my map from one location to another location....i am quite new to android..and i found out how to draw a line in between two locations..
public class Mapview extends MapActivity implements LocationListener{
MapController mc;
GeoPoint p,p1,p2;
LocationManager lm;
String provider;
class Mapoverlay extends com.google.android.maps.Overlay
{
@Override
public boolean draw(Canvas canvas, MapView mapView, boolean shadow,
long when) {
// TODO Auto-generated method stub
super.draw(canvas, mapView, shadow);
Point screenpoints=new Point();
Point screenpoints1=new Point();
Point screenpoints2=new Point();
Paint paint;
paint = new Paint();
paint.setColor(Color.RED);
paint.setAntiAlias(true);
paint.setStyle(Style.FILL);
paint.setStrokeWidth(2);
paint.setAlpha(120);
Paint paint1;
paint1 = new Paint();
paint1.setColor(Color.BLUE);
paint1.setAntiAlias(true);
paint1.setStyle(Style.FILL);
paint1.setStrokeWidth(2);
paint1.setAlpha(120);
if(p != null)
{
mapView.getProjection().toPixels(p, screenpoints);
mapView.getProjection().toPixels(p1, screenpoints1);
mapView.getProjection().toPixels(p2, screenpoints2);
// Bitmap map=BitmapFactory.decodeResource(getResources(), R.drawable.pushpin1);
// canvas.drawBitmap(map, screenpoints.x, screenpoints.y-53, null);
canvas.drawLine(screenpoints.x,screenpoints.y,screenpoints1.x,screenpoints1.y, paint);
canvas.drawLine(screenpoints.x,screenpoints.y,screenpoints2.x,screenpoints2.y, paint);
}
return true;
}
}
@Override
protected void onCreate(Bundle icicle) {
// TODO Auto-generated method stub
super.onCreate(icicle);
setContentView(R.layout.mapview);
MapView map=(MapView)findViewById(R.id.mapView);
map.setBuiltInZoomControls(true);
mc=map.getController();
String[] coordinates={"51.4750766129036", "-3.15672342166522"};
double lat = Double.parseDouble(coordinates[0]);
double lng = Double.parseDouble(coordinates[1]);
p=new GeoPoint((int)(lat*1E6), (int)(lng*1E6));
String[] coordinates1={"17.453117" , "78.467586" };
double lat1 = Double.parseDouble(coordinates1[0]);
double lng1 = Double.parseDouble(coordinates1[1]);
p2=new GeoPoint((int)(lat1*1E6), (int)(lng1*1E6));
p1 = new GeoPoint(19240000,-99120000);
// p = new GeoPoint(19241000,-99121000);
lm=(LocationManager)getSystemService(Context.LOCATION_SERVICE);
Criteria criteria = new Criteria();
criteria.setAccuracy(Criteria.ACCURACY_FINE);
criteria.setAltitudeRequired(false);
criteria.setBearingRequired(false);
criteria.setCostAllowed(true);
criteria.setPowerRequirement(Criteria.POWER_LOW);
provider=lm.getBestProvider(criteria, true);
Location loc=lm.getLastKnownLocation(LocationManager.GPS_PROVIDER);
List<String> lists=lm.getAllProviders();
// float f=loc.distanceTo(loc);
if (loc!=null){
System.out.println("Provider " + provider + " has been selected.");
onLocationChanged(loc);
}else{
Toast.makeText(getApplicationContext(), "Provider " + provider+ loc + lists+" has not been selected.", 5000).show();
// this.finish();
}
// Toast.makeText(getApplicationContext(), p.getLatitudeE6()+p.getLongitudeE6(), Toast.LENGTH_SHORT).show();
mc.animateTo(p);
mc.setZoom(1);
map.invalidate();
Mapoverlay mapOverlay = new Mapoverlay();
List<Overlay> listOfOverlays = map.getOverlays();
listOfOverlays.clear();
listOfOverlays.add(mapOverlay);
}
i am stuck at moving map from one location to another without user activity
for example:when the app initiates location of newyork city is shown then the map should move to texas ...any help willl be grateful
回答1:
Try This class just pass Activity act,GeoPoint src,GeoPoint dest, int color, MapView mMapView
To call this class do this
new getRoute().DrawPath(this,mGeoPoint,getGeoPoint,Color.RED,mMapView);
public class getRoute
{
/*Variable*/
double mIntentLatitude, mIntentLongitude;
double mCursorLatitude, mCursorLongitude, mStartLatitude, mStartLongitude, mEndLatitude, MEndLongitude;
String mJsonData;
String mEnd_Address, mStart_Address, mName;
int mLength;
GeoPoint mGeoPoint = new GeoPoint(220328269, 725588202);
double mLatitude_End[], mLongitude_End[], mLatitude_Start[], mLongitude_Start[];
Activity activity;
public getRoute
(){
}
boolean error = false;
public void DrawPath(Activity act,GeoPoint src,GeoPoint dest, int color, MapView mMapView01)
{
// connect to map web service
DrawPathBack draw = new DrawPathBack(act, src, dest, color, mMapView01);
draw.execute("Draw");
}
public class DrawPathBack extends AsyncTask<String, Integer,Void>
{
ProgressDialog bar;
List<Overlay> mListOverlay;
MapOverlay mapOverlay;
ItemizedOverlay<OverlayItem> mItemizedOverlay;
GeoPoint src,dest;
int color;
MapView mMapView;
CommonMethod mCommonMethod;
String [] pairs;
String[] lngLat;
public DrawPathBack(Activity act,GeoPoint gpsrc,GeoPoint gpdest, int c, MapView mMap)
{
activity =act;
src=gpsrc;
dest=gpdest;
color = c;
mMapView=mMap;
mListOverlay = mMapView.getOverlays();
mapOverlay = new MapOverlay(mGeoPoint);
mListOverlay.add(mapOverlay);
mMapView.invalidate();
}
@Override
protected Void doInBackground(String... params)
{
HttpParams httpParameters = new BasicHttpParams();
HttpConnectionParams.setSoTimeout(httpParameters, 60000);
HttpClient client = new DefaultHttpClient();
try {
HttpPost httpPost = new HttpPost("http://maps.googleapis.com/maps/api/directions/json?origin="+ (Double.toString((double)src.getLatitudeE6()/1.0E6)) + "," +(Double.toString((double)src.getLongitudeE6()/1.0E6 ) + "&destination=" + (Double.toString((double)dest.getLatitudeE6()/1.0E6)) + ","+ (Double.toString((double)dest.getLongitudeE6()/1.0E6))+ "&sensor=false"));
mIntentLatitude=((double)src.getLatitudeE6()/1.0E6);
mIntentLongitude=((double)src.getLongitudeE6()/1.0E6);
//httpPost.setEntity(new UrlEncodedFormEntity(nameValuePairs));
HttpResponse httpResponse = client.execute(httpPost);
mJsonData = EntityUtils.toString(httpResponse.getEntity());
} catch (ClientProtocolException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return null;
}
@Override
protected void onProgressUpdate(Integer... progress)
{
bar.setMessage("Time Progress "+progress[0]);
}
@Override
protected void onPostExecute(Void result)
{
try {
JSONObject jsonObj = new JSONObject(mJsonData);
// grabbing the routes object
JSONArray routes = jsonObj.getJSONArray("routes");
for (int i = 0; i < routes.length(); i++) {
JSONObject rout = routes.getJSONObject(i);
JSONObject bounds = rout.getJSONObject("bounds");
JSONObject northest = bounds.getJSONObject("northeast");
mStartLatitude = northest.getDouble("lat");
mStartLongitude = northest.getDouble("lng");
JSONObject southwest = bounds.getJSONObject("southwest");
mEndLatitude = southwest.getDouble("lat");
MEndLongitude = southwest.getDouble("lng");
System.out.println("get data from jeson" + mCursorLatitude + mCursorLongitude + mEndLatitude
+ MEndLongitude);
// grabbing the routes legs
JSONArray legs = rout.getJSONArray("legs");
System.out.println("length of legs array " + legs.length());
for (int j = 0; j < legs.length(); j++) {
JSONObject leg = legs.getJSONObject(j);
System.out.println("enter in second array");
JSONObject distance = leg.getJSONObject("distance");
String mTextDistent = distance.getString("text");
System.out.println("distances bitween two point" + mTextDistent);
JSONObject duration = leg.getJSONObject("duration");
String mTextDurestion = duration.getString("text");
mEnd_Address = leg.getString("end_address");
mStart_Address = leg.getString("start_address");
System.out.println("get data from jeson in second arry"
+ mTextDurestion + " " + mEnd_Address + " " + mStart_Address);
JSONArray step = leg.getJSONArray("steps");
mLength = step.length();
mLatitude_End = new double[mLength];
mLongitude_End = new double[mLength];
mLatitude_Start = new double[mLength];
mLongitude_Start = new double[mLength];
for (int k = 0; k < step.length(); k++) {
JSONObject st = step.getJSONObject(k);
System.out.println("enter in third array");
JSONObject end_lo = st.getJSONObject("end_location");
JSONObject start_lo = st
.getJSONObject("start_location");
mLatitude_End[k] = end_lo.getDouble("lat");
mLongitude_End[k] = end_lo.getDouble("lng");
mLatitude_Start[k] = start_lo.getDouble("lat");
mLongitude_Start[k] = start_lo.getDouble("lng");
}
for (int mDistanse = 0; mDistanse < mLength; mDistanse++) {
System.out.println("end location let" + mLatitude_End[mDistanse]);
System.out.println("end location long+"
+ mLongitude_End[mDistanse]);
System.out.println("Start location let"
+ mLatitude_Start[mDistanse]);
System.out.println("Start location long"
+ mLongitude_Start[mDistanse]);
}
}
}
} catch (Exception e) {
// TODO: handle exception
e.printStackTrace();
}
}
}
public class MapOverlay extends com.google.android.maps.Overlay {
public MapOverlay(GeoPoint mGeoPoint) {
}
@Override
public boolean draw(final Canvas canvas, MapView mapView,
boolean shadow, long when) {
Point mpoint = new Point();
Point mpoint1 = new Point();
int let[] = new int[mLength];
int lon[] = new int[mLength];
int let_end[] = new int[mLength];
int lon_end[] = new int[mLength];
GeoPoint newGeoPoint = null;
GeoPoint newGeoPoint1;
for (int k = 0; k < mLength; k++) {
let[k] = (int) (mLatitude_Start[k] * 1E6);
lon[k] = (int) (mLongitude_Start[k] * 1E6);
let_end[k] = (int) (mLatitude_End[k] * 1E6);
lon_end[k] = (int) (mLongitude_End[k] * 1E6);
newGeoPoint1 = new GeoPoint(let_end[k], lon_end[k]);
newGeoPoint = new GeoPoint(let[k], lon[k]);
mapView.getProjection().toPixels(newGeoPoint, mpoint);
mapView.getProjection().toPixels(newGeoPoint1, mpoint1);
Paint paint = new Paint();
paint.setColor(Color.RED);
paint.setStyle(Paint.Style.FILL_AND_STROKE);
paint.setStrokeWidth(5);
canvas.drawCircle(mpoint.x, mpoint.y, 5, paint);
paint.setColor(Color.BLUE);
canvas.drawLine(mpoint.x, mpoint.y, mpoint1.x, mpoint1.y, paint);
paint.setColor(Color.BLACK);
paint.setStrokeWidth(100);
paint.setStyle(Paint.Style.FILL);
if(k==mLength-1){
Bitmap bmp = BitmapFactory.decodeResource(activity.getResources(), R.drawable.green_pin);
canvas.drawBitmap(bmp,mpoint1.x ,mpoint1.y-30, null);
}
GeoPoint dumy=new GeoPoint((int)(mIntentLatitude * 1E6), (int)(mIntentLongitude * 1E6));
Point dumy1 = new Point();
mapView.getProjection().toPixels(dumy, dumy1);
Bitmap bmp = BitmapFactory.decodeResource(activity.getResources(), R.drawable.dest_pin);
canvas.drawBitmap(bmp,dumy1.x,dumy1.y - 25, null);
mapView.getController().animateTo(dumy);
mapView.invalidate();
}
return false;
}
}
}
回答2:
Try this if you want to move map on particular position then get lat or long of that position and just pass in this :
MapController mMapController;
mMapController=mMapView.getController();
mMapController.setCenter(new GeoPoint((int)(lat * 1E6), (int)(lon * 1E6)));
and if you want to draw path between two location then just pass lat and lon in this :
Intent intent = new Intent(android.content.Intent.ACTION_VIEW,
Uri.parse("http://maps.google.com/maps?saddr="+ String.valueOf(from_lattitude) +","+ String.valueOf(from_longitude) +"&daddr="+ String.valueOf(dest_lati) +","+ String.valueOf(dest_longi)));
startActivity(intent);
来源：https://stackoverflow.com/questions/13246084/moving-map-in-mapview-from-one-location-to-another-in-android