在地图上获取当前位置

Question

我想在地图上获取当前位置并绘制从当前点到未知点的路线。通过步行绘制路线。我已经集成了谷歌地图，但我不知道如何获取当前位置。我试过这个但没有找到位置.

SupportMapFragment mapFragment = (SupportMapFragment) getSupportFragmentManager()
            .findFragmentById(R.id.map);
    mapFragment.getMapAsync(this);



public void onMapReady(GoogleMap mMap) {

    googleMap=mMap;


    if (googleMap != null) {
        if (ActivityCompat.checkSelfPermission(this, android.Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(this, android.Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED)
        {
          // TODO: Consider calling
          // ActivityCompat#requestPermissions
          // here to request the missing permissions, and then overriding
          // public void onRequestPermissionsResult(int requestCode, String[] permissions,
           // int[] grantResults)
          // to handle the case where the user grants the permission. See the documentation
          // for ActivityCompat#requestPermissions for more details.

            try {
                if (PreferenceClass.getStringPreferences(mContext, Constant.CURRENT_LATITUDE).trim().length() > 0) {
                    LatLng latLng = new LatLng(Double.parseDouble(PreferenceClass.getStringPreferences(mContext, Constant.CURRENT_LATITUDE)), Double.parseDouble(PreferenceClass.getStringPreferences(mContext, Constant.CURRENT_LONGITUDE)));
                    Log.d("latLng", latLng.toString());
                    googleMap.addMarker(new MarkerOptions().position(latLng).title("My Location").icon(BitmapDescriptorFactory.fromResource(R.drawable.profile)));
                    googleMap.moveCamera(CameraUpdateFactory.newLatLng(latLng));
                    googleMap.animateCamera(CameraUpdateFactory.zoomTo(15));
                    googleMap.setMyLocationEnabled(true);
                }
            } catch (Exception e) {
                e.printStackTrace();
            }
            return;
        }
        googleMap.setMyLocationEnabled(true);
        googleMap.getUiSettings().setRotateGesturesEnabled(true);
        googleMap.getUiSettings().setZoomControlsEnabled(true);
        googleMap.getUiSettings().setZoomGesturesEnabled(true);

        LocationManager locationManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
        locationManager.requestLocationUpdates(LocationManager.NETWORK_PROVIDER, 1, 1, this);
    }
}

public void onLocationChanged(Location location) {
    googleMap.clear();
    LatLng latLng = new LatLng(location.getLatitude(), location.getLongitude());
    MarkerOptions markerOptions = new MarkerOptions();
    markerOptions.position(latLng);
    markerOptions.title("My Location");
    googleMap.addMarker(markerOptions);
    googleMap.animateCamera(CameraUpdateFactory.newLatLngZoom(latLng, 17.0f));
}

Answer 1

尝试使用此类获取纬度和经度..

import android.app.AlertDialog.Builder;
import android.app.Service;
import android.content.Context;
import android.content.DialogInterface;
import android.content.Intent;
import android.location.Location;
import android.location.LocationListener;
import android.location.LocationManager;
import android.os.Bundle;
import android.os.IBinder;
import android.provider.Settings;

public class GPSTracker extends Service implements LocationListener {


private Context context;

boolean isGPSEnabled=false;
boolean isNetworkEnabled=false;
boolean canGetLocation=false;

Location location;

double latitude;
double longitude;

private static final long MIN_DISTANCE_CHANGE_FOR_UPDATES=10;
private static final long MIN_TIME_BW_UPDATES=1000*60*1;

protected LocationManager locationManager;

public GPSTracker(Context context)
{
    this.context=context;
getLocation();
}

public Location getLocation()
{
    try{
    locationManager=(LocationManager) context.getSystemService(LOCATION_SERVICE);
    isGPSEnabled=locationManager.isProviderEnabled(LocationManager.GPS_PROVIDER);
    isNetworkEnabled=locationManager.isProviderEnabled(LocationManager.NETWORK_PROVIDER);




    if(!isGPSEnabled && !isNetworkEnabled)
    {
        showSettingsAlert();
    }
    else{
        this.canGetLocation=true;
        if(isNetworkEnabled)
        {
            locationManager.requestLocationUpdates(LocationManager.NETWORK_PROVIDER, MIN_TIME_BW_UPDATES, MIN_DISTANCE_CHANGE_FOR_UPDATES, this);


        if(locationManager !=null)
        {
            location=locationManager.getLastKnownLocation(LocationManager.NETWORK_PROVIDER);

        if(location !=null)
        {
            latitude=location.getLatitude();
            longitude=location.getLongitude();
        }
        }
        }

        if(isGPSEnabled){
            if(location==null)
            {
                locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, MIN_TIME_BW_UPDATES, MIN_DISTANCE_CHANGE_FOR_UPDATES, this);

                if(locationManager !=null)
                {
                    location=locationManager.getLastKnownLocation(LocationManager.GPS_PROVIDER);

                    if(location !=null)
                    {
                        latitude=location.getLatitude();
                        longitude=location.getLongitude();
                    }   

                }

            }
        }


    }


    }
    catch(Exception e)
    {
        e.printStackTrace();
    }
    return location;
}

public void stopUsingGPS()
{
    if(locationManager !=null)
    {
        locationManager.removeUpdates(GPSTracker.this);
    }
}

public double getLatitude()
{
    if(location!=null)
    {
        latitude=location.getLatitude();
    }
    return latitude;

}


public double getLongitude()
{
    if(location!=null)
    {
        longitude=location.getLongitude();
    }
    return longitude;

}

public boolean canGetLocation(){

return this.canGetLocation;

}

public void showSettingsAlert(){
    Builder alertDialog=new Builder(context);
    alertDialog.setTitle("GPS Settings");
    alertDialog.setMessage("GPS is not enabled.Do you want to go to the settings menu?");
    alertDialog.setPositiveButton("Settings", new DialogInterface.OnClickListener() {

        @Override
        public void onClick(DialogInterface dialog, int which) {
            Intent intent=new Intent(Settings.ACTION_LOCATION_SOURCE_SETTINGS);
            context.startActivity(intent);
        }
    }); 

    alertDialog.setNegativeButton("Cancel", new DialogInterface.OnClickListener() {

        @Override
        public void onClick(DialogInterface dialog, int which) {
            dialog.cancel();

        }
    });
    alertDialog.show();
}


@Override
public void onLocationChanged(Location location) {
    // TODO Auto-generated method stub

}

@Override
public void onStatusChanged(String provider, int status, Bundle extras) {
    // TODO Auto-generated method stub

}

@Override
public void onProviderEnabled(String provider) {
    // TODO Auto-generated method stub

}

@Override
public void onProviderDisabled(String provider) {
    // TODO Auto-generated method stub

}

@Override
public IBinder onBind(Intent intent) {
    // TODO Auto-generated method stub
    return null;
}


}

并使用此标记您在地图中的位置。

import android.os.Bundle;
import android.support.v4.app.FragmentActivity;
import com.google.android.gms.maps.CameraUpdateFactory;
import com.google.android.gms.maps.GoogleMap;
import com.google.android.gms.maps.OnMapReadyCallback;
import com.google.android.gms.maps.SupportMapFragment;
import com.google.android.gms.maps.model.LatLng;
import com.google.android.gms.maps.model.MarkerOptions;

 public class MapsActivity extends FragmentActivity implements OnMapReadyCallback {

private GoogleMap mMap;
GPSTracker gps;
@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_maps);
    // Obtain the SupportMapFragment and get notified when the map is ready to be used.
    SupportMapFragment mapFragment = (SupportMapFragment) getSupportFragmentManager()
            .findFragmentById(R.id.map);
    mapFragment.getMapAsync(this);
}



@Override
public void onMapReady(GoogleMap googleMap) {
    mMap = googleMap;



    try {

        gps = new GPSTracker(MapsActivity.this);

        if (gps.canGetLocation) {
            double latitude = gps.getLatitude();
            double longitude = gps.getLongitude();
            LatLng sydney = new LatLng(latitude, longitude);
            mMap.addMarker(new MarkerOptions().position(sydney).title("I am here"));
            mMap.moveCamera(CameraUpdateFactory.newLatLng(sydney));
            mMap.animateCamera(CameraUpdateFactory.zoomTo(10), 2000, null);

            for(int i=0;i<MainActivity.nameArray.length;i++)
            {
                latitude=Double.parseDouble(MainActivity.latArray[i]);
                longitude=Double.parseDouble(MainActivity.lonArray[i]);
                LatLng shops = new LatLng(latitude, longitude);
                mMap.addMarker(new MarkerOptions().position(shops).title(MainActivity.nameArray[i]));

            }





        } else {
            gps.showSettingsAlert();
        }

    } catch (Exception e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }



 }
}

希望这会有所帮助..祝你好运